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Hönigsperger C, Storm JF, Arena A. Laminar evoked responses in mouse somatosensory cortex suggest a special role for deep layers in cortical complexity. Eur J Neurosci 2024; 59:752-770. [PMID: 37586411 DOI: 10.1111/ejn.16108] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2022] [Revised: 07/03/2023] [Accepted: 07/20/2023] [Indexed: 08/18/2023]
Abstract
It has been suggested that consciousness is closely related to the complexity of the brain. The perturbational complexity index (PCI) has been used in humans and rodents to distinguish conscious from unconscious states based on the global cortical responses (recorded by electroencephalography, EEG) to local cortical stimulation (CS). However, it is unclear how different cortical layers respond to CS and contribute to the resulting intra- and inter-areal cortical connectivity and PCI. A detailed investigation of the local dynamics is needed to understand the basis for PCI. We hypothesized that the complexity level of global cortical responses (PCI) correlates with layer-specific activity and connectivity. We tested this idea by measuring global cortical dynamics and layer-specific activity in the somatosensory cortex (S1) of mice, combining cortical electrical stimulation in deep motor cortex, global electrocorticography (ECoG) and local laminar recordings from layers 1-6 in S1, during wakefulness and general anaesthesia (sevoflurane). We found that the transition from wake to sevoflurane anaesthesia correlated with a drop in both the global and local PCI (PCIst ) values (complexity). This was accompanied by a local decrease in neural firing rate, spike-field coherence and long-range functional connectivity specific to deep layers (L5, L6). Our results suggest that deep cortical layers are mechanistically important for changes in PCI and thereby for changes in the state of consciousness.
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Affiliation(s)
| | - Johan F Storm
- Department of Molecular Medicine, University of Oslo, Oslo, Norway
| | - Alessandro Arena
- Department of Molecular Medicine, University of Oslo, Oslo, Norway
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2
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Lowet AS, Zheng Q, Meng M, Matias S, Drugowitsch J, Uchida N. An opponent striatal circuit for distributional reinforcement learning. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.01.02.573966. [PMID: 38260354 PMCID: PMC10802299 DOI: 10.1101/2024.01.02.573966] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/24/2024]
Abstract
Machine learning research has achieved large performance gains on a wide range of tasks by expanding the learning target from mean rewards to entire probability distributions of rewards - an approach known as distributional reinforcement learning (RL)1. The mesolimbic dopamine system is thought to underlie RL in the mammalian brain by updating a representation of mean value in the striatum2,3, but little is known about whether, where, and how neurons in this circuit encode information about higher-order moments of reward distributions4. To fill this gap, we used high-density probes (Neuropixels) to acutely record striatal activity from well-trained, water-restricted mice performing a classical conditioning task in which reward mean, reward variance, and stimulus identity were independently manipulated. In contrast to traditional RL accounts, we found robust evidence for abstract encoding of variance in the striatum. Remarkably, chronic ablation of dopamine inputs disorganized these distributional representations in the striatum without interfering with mean value coding. Two-photon calcium imaging and optogenetics revealed that the two major classes of striatal medium spiny neurons - D1 and D2 MSNs - contributed to this code by preferentially encoding the right and left tails of the reward distribution, respectively. We synthesize these findings into a new model of the striatum and mesolimbic dopamine that harnesses the opponency between D1 and D2 MSNs5-15 to reap the computational benefits of distributional RL.
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Affiliation(s)
- Adam S Lowet
- Center for Brain Science, Harvard University, Cambridge, MA, USA
- Department of Molecular and Cellular Biology, Harvard University, Cambridge, MA, USA
- Program in Neuroscience, Harvard University, Boston, MA, USA
| | - Qiao Zheng
- Center for Brain Science, Harvard University, Cambridge, MA, USA
- Department of Neurobiology, Harvard Medical School, Boston, MA, USA
| | - Melissa Meng
- Center for Brain Science, Harvard University, Cambridge, MA, USA
- Department of Molecular and Cellular Biology, Harvard University, Cambridge, MA, USA
| | - Sara Matias
- Center for Brain Science, Harvard University, Cambridge, MA, USA
- Department of Molecular and Cellular Biology, Harvard University, Cambridge, MA, USA
| | - Jan Drugowitsch
- Center for Brain Science, Harvard University, Cambridge, MA, USA
- Department of Neurobiology, Harvard Medical School, Boston, MA, USA
| | - Naoshige Uchida
- Center for Brain Science, Harvard University, Cambridge, MA, USA
- Department of Molecular and Cellular Biology, Harvard University, Cambridge, MA, USA
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3
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Horváth C, Ulbert I, Fiáth R. Propagating population activity patterns during spontaneous slow waves in the thalamus of rodents. Neuroimage 2024; 285:120484. [PMID: 38061688 DOI: 10.1016/j.neuroimage.2023.120484] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2023] [Revised: 11/08/2023] [Accepted: 12/04/2023] [Indexed: 01/13/2024] Open
Abstract
Slow waves (SWs) represent the most prominent electrophysiological events in the thalamocortical system under anesthesia and during deep sleep. Recent studies have revealed that SWs have complex spatiotemporal dynamics and propagate across neocortical regions. However, it is still unclear whether neuronal activity in the thalamus exhibits similar propagation properties during SWs. Here, we report propagating population activity in the thalamus of ketamine/xylazine-anesthetized rats and mice visualized by high-density silicon probe recordings. In both rodent species, propagation of spontaneous thalamic activity during up-states was most frequently observed in dorsal thalamic nuclei such as the higher order posterior (Po), lateral posterior (LP) or laterodorsal (LD) nuclei. The preferred direction of thalamic activity spreading was along the dorsoventral axis, with over half of the up-states exhibiting a gradual propagation in the ventral-to-dorsal direction. Furthermore, simultaneous neocortical and thalamic recordings collected under anesthesia demonstrated that there is a weak but noticeable interrelation between propagation patterns observed during cortical up-states and those displayed by thalamic population activity. In addition, using chronically implanted silicon probes, we detected propagating activity patterns in the thalamus of naturally sleeping rats during slow-wave sleep. However, in comparison to propagating up-states observed under anesthesia, these propagating patterns were characterized by a reduced rate of occurrence and a faster propagation speed. Our findings suggest that the propagation of spontaneous population activity is an intrinsic property of the thalamocortical network during synchronized brain states such as deep sleep or anesthesia. Additionally, our data implies that the neocortex may have partial control over the formation of propagation patterns within the dorsal thalamus under anesthesia.
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Affiliation(s)
- Csaba Horváth
- Institute of Cognitive Neuroscience and Psychology, Research Centre for Natural Sciences, Eötvös Loránd Research Network, Budapest, Hungary; János Szentágothai Doctoral School of Neurosciences, Semmelweis University, Budapest, Hungary
| | - István Ulbert
- Institute of Cognitive Neuroscience and Psychology, Research Centre for Natural Sciences, Eötvös Loránd Research Network, Budapest, Hungary; Faculty of Information Technology and Bionics, Pázmány Péter Catholic University, Budapest, Hungary.
| | - Richárd Fiáth
- Institute of Cognitive Neuroscience and Psychology, Research Centre for Natural Sciences, Eötvös Loránd Research Network, Budapest, Hungary; Faculty of Information Technology and Bionics, Pázmány Péter Catholic University, Budapest, Hungary
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4
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Ochoa JÁ, Gonzalez-Burgos I, Nicolás MJ, Valencia M. Open Hardware Implementation of Real-Time Phase and Amplitude Estimation for Neurophysiologic Signals. Bioengineering (Basel) 2023; 10:1350. [PMID: 38135941 PMCID: PMC10740741 DOI: 10.3390/bioengineering10121350] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2023] [Revised: 11/16/2023] [Accepted: 11/21/2023] [Indexed: 12/24/2023] Open
Abstract
Adaptive deep brain stimulation (aDBS) is a promising concept in the field of DBS that consists of delivering electrical stimulation in response to specific events. Dynamic adaptivity arises when stimulation targets dynamically changing states, which often calls for a reliable and fast causal estimation of the phase and amplitude of the signals. Here, we present an open-hardware implementation that exploits the concepts of resonators and Hilbert filters embedded in an open-hardware platform. To emulate real-world scenarios, we built a hardware setup that included a system to replay and process different types of physiological signals and test the accuracy of the instantaneous phase and amplitude estimates. The results show that the system can provide a precise and reliable estimation of the phase even in the challenging scenario of dealing with high-frequency oscillations (~250 Hz) in real-time. The framework might be adopted in neuromodulation studies to quickly test biomarkers in clinical and preclinical settings, supporting the advancement of aDBS.
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Affiliation(s)
- José Ángel Ochoa
- Biomedical Engineering Program, Physiological Monitoring and Control Laboratory, CIMA, Universidad de Navarra, Avda Pio XII 55, 31080 Pamplona, Spain; (J.Á.O.); (I.G.-B.); (M.J.N.)
- IdiSNA, Navarra Institute for Health Research, C/Irunlarrea, 31008 Pamplona, Spain
| | - Irene Gonzalez-Burgos
- Biomedical Engineering Program, Physiological Monitoring and Control Laboratory, CIMA, Universidad de Navarra, Avda Pio XII 55, 31080 Pamplona, Spain; (J.Á.O.); (I.G.-B.); (M.J.N.)
- IdiSNA, Navarra Institute for Health Research, C/Irunlarrea, 31008 Pamplona, Spain
| | - María Jesús Nicolás
- Biomedical Engineering Program, Physiological Monitoring and Control Laboratory, CIMA, Universidad de Navarra, Avda Pio XII 55, 31080 Pamplona, Spain; (J.Á.O.); (I.G.-B.); (M.J.N.)
- IdiSNA, Navarra Institute for Health Research, C/Irunlarrea, 31008 Pamplona, Spain
| | - Miguel Valencia
- Biomedical Engineering Program, Physiological Monitoring and Control Laboratory, CIMA, Universidad de Navarra, Avda Pio XII 55, 31080 Pamplona, Spain; (J.Á.O.); (I.G.-B.); (M.J.N.)
- IdiSNA, Navarra Institute for Health Research, C/Irunlarrea, 31008 Pamplona, Spain
- Institute of Data Science and Artificial Intelligence, Universidad de Navarra, Campus Universitario, 31009 Pamplona, Spain
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5
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Huang Z, Chung M, Tao K, Watarai A, Wang MY, Ito H, Okuyama T. Ventromedial prefrontal neurons represent self-states shaped by vicarious fear in male mice. Nat Commun 2023; 14:3458. [PMID: 37400435 DOI: 10.1038/s41467-023-39081-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2022] [Accepted: 05/26/2023] [Indexed: 07/05/2023] Open
Abstract
Perception of fear induced by others in danger elicits complex vicarious fear responses and behavioral outputs. In rodents, observing a conspecific receive aversive stimuli leads to escape and freezing behavior. It remains unclear how these behavioral self-states in response to others in fear are neurophysiologically represented. Here, we assess such representations in the ventromedial prefrontal cortex (vmPFC), an essential site for empathy, in an observational fear (OF) paradigm in male mice. We classify the observer mouse's stereotypic behaviors during OF using a machine-learning approach. Optogenetic inhibition of the vmPFC specifically disrupts OF-induced escape behavior. In vivo Ca2+ imaging reveals that vmPFC neural populations represent intermingled information of other- and self-states. Distinct subpopulations are activated and suppressed by others' fear responses, simultaneously representing self-freezing states. This mixed selectivity requires inputs from the anterior cingulate cortex and the basolateral amygdala to regulate OF-induced escape behavior.
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Affiliation(s)
- Ziyan Huang
- Laboratory of Behavioral Neuroscience, Institute for Quantitative Biosciences (IQB), The University of Tokyo, Tokyo, Japan
- Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
| | - Myung Chung
- Laboratory of Behavioral Neuroscience, Institute for Quantitative Biosciences (IQB), The University of Tokyo, Tokyo, Japan
- Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
| | - Kentaro Tao
- Laboratory of Behavioral Neuroscience, Institute for Quantitative Biosciences (IQB), The University of Tokyo, Tokyo, Japan
| | - Akiyuki Watarai
- Laboratory of Behavioral Neuroscience, Institute for Quantitative Biosciences (IQB), The University of Tokyo, Tokyo, Japan
| | - Mu-Yun Wang
- Laboratory of Behavioral Neuroscience, Institute for Quantitative Biosciences (IQB), The University of Tokyo, Tokyo, Japan
| | - Hiroh Ito
- Laboratory of Behavioral Neuroscience, Institute for Quantitative Biosciences (IQB), The University of Tokyo, Tokyo, Japan
- Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
| | - Teruhiro Okuyama
- Laboratory of Behavioral Neuroscience, Institute for Quantitative Biosciences (IQB), The University of Tokyo, Tokyo, Japan.
- Graduate School of Medicine, The University of Tokyo, Tokyo, Japan.
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6
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Yeganegi H, Ondracek JM. Multi-channel recordings reveal age-related differences in the sleep of juvenile and adult zebra finches. Sci Rep 2023; 13:8607. [PMID: 37244927 DOI: 10.1038/s41598-023-35160-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2022] [Accepted: 05/13/2023] [Indexed: 05/29/2023] Open
Abstract
Despite their phylogenetic differences and distinct pallial structures, mammals and birds show similar electroencephalography (EEG) traces during sleep, consisting of distinct rapid eye movement (REM) sleep and slow wave sleep (SWS) stages. Studies in human and a limited number of other mammalian species show that this organization of sleep into interleaving stages undergoes radical changes during lifetime. Do these age-dependent variations in sleep patterns also occur in the avian brain? Does vocal learning have an effect on sleep patterns in birds? To answer these questions, we recorded multi-channel sleep EEG from juvenile and adult zebra finches for several nights. Whereas adults spent more time in SWS and REM sleep, juveniles spent more time in intermediate sleep (IS). The amount of IS was significantly larger in male juveniles engaged in vocal learning compared to female juveniles, which suggests that IS could be important for vocal learning. In addition, we observed that functional connectivity increased rapidly during maturation of young juveniles, and was stable or declined at older ages. Synchronous activity during sleep was larger for recording sites in the left hemisphere for both juveniles and adults, and generally intra-hemispheric synchrony was larger than inter-hemispheric synchrony during sleep. A graph theory analysis revealed that in adults, highly correlated EEG activity tended to be distributed across fewer networks that were spread across a wider area of the brain, whereas in juveniles, highly correlated EEG activity was distributed across more numerous, albeit smaller, networks in the brain. Overall, our results reveal that significant changes occur in the neural signatures of sleep during maturation in an avian brain.
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Affiliation(s)
- Hamed Yeganegi
- Technical University of Munich, Liesel-Beckmann-Str. 4, 85354, Freising-Weihenstephan, Germany
- Graduate School of Systemic Neurosciences, Ludwig-Maximilians-University Munich, Großhaderner Str. 2, 82152, Planegg, Germany
| | - Janie M Ondracek
- Technical University of Munich, Liesel-Beckmann-Str. 4, 85354, Freising-Weihenstephan, Germany.
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7
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Dagher S, Ishiyama S. Protocol for precise signal synchronization of electrophysiology, videography, and audio recordings using a custom-made pulse generator. STAR Protoc 2023; 4:102306. [PMID: 37178112 DOI: 10.1016/j.xpro.2023.102306] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2023] [Revised: 04/06/2023] [Accepted: 04/23/2023] [Indexed: 05/15/2023] Open
Abstract
Precise signal synchronization is vital for accurate analysis in systems neuroscience. Here, we present a protocol for synchronizing electrophysiology, videography, and audio recordings using a custom-made pulse generator. We describe steps for building the pulse generator, installing software, connecting devices, and running experimental sessions. We then detail signal analysis, temporal alignment, and duration normalization. This protocol offers flexibility and cost-effectiveness, addressing limited shared knowledge and providing a solution for signal synchronization in various experimental setups.
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Affiliation(s)
- Sarah Dagher
- Universitätsmedizin der Johannes Gutenberg-Universität Mainz, Institut für Pathophysiologie, 55128 Mainz, Germany
| | - Shimpei Ishiyama
- Universitätsmedizin der Johannes Gutenberg-Universität Mainz, Institut für Pathophysiologie, 55128 Mainz, Germany.
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8
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Szadai Z, Pi HJ, Chevy Q, Ócsai K, Albeanu DF, Chiovini B, Szalay G, Katona G, Kepecs A, Rózsa B. Cortex-wide response mode of VIP-expressing inhibitory neurons by reward and punishment. eLife 2022; 11:78815. [PMID: 36416886 PMCID: PMC9683790 DOI: 10.7554/elife.78815] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2022] [Accepted: 10/23/2022] [Indexed: 11/24/2022] Open
Abstract
Neocortex is classically divided into distinct areas, each specializing in different function, but all could benefit from reinforcement feedback to inform and update local processing. Yet it remains elusive how global signals like reward and punishment are represented in local cortical computations. Previously, we identified a cortical neuron type, vasoactive intestinal polypeptide (VIP)-expressing interneurons, in auditory cortex that is recruited by behavioral reinforcers and mediates disinhibitory control by inhibiting other inhibitory neurons. As the same disinhibitory cortical circuit is present virtually throughout cortex, we wondered whether VIP neurons are likewise recruited by reinforcers throughout cortex. We monitored VIP neural activity in dozens of cortical regions using three-dimensional random access two-photon microscopy and fiber photometry while mice learned an auditory discrimination task. We found that reward and punishment during initial learning produce rapid, cortex-wide activation of most VIP interneurons. This global recruitment mode showed variations in temporal dynamics in individual neurons and across areas. Neither the weak sensory tuning of VIP interneurons in visual cortex nor their arousal state modulation was fully predictive of reinforcer responses. We suggest that the global response mode of cortical VIP interneurons supports a cell-type-specific circuit mechanism by which organism-level information about reinforcers regulates local circuit processing and plasticity.
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Affiliation(s)
- Zoltán Szadai
- Laboratory of 3D functional network and dendritic imaging, Institute of Experimental Medicine
- MTA-PPKE ITK-NAP B – 2p Measurement Technology Group, The Faculty of Information Technology, Pázmány Péter Catholic University
- János Szentágothai Doctoral School of Neurosciences, Semmelweis University
- BrainVisionCenter
| | - Hyun-Jae Pi
- Cold Spring Harbor Laboratory
- Volen Center for Complex Systems, Biology Department, Brandeis University
| | - Quentin Chevy
- Cold Spring Harbor Laboratory
- Departments of Neuroscience and Psychiatry, Washington University School of Medicine
| | - Katalin Ócsai
- MTA-PPKE ITK-NAP B – 2p Measurement Technology Group, The Faculty of Information Technology, Pázmány Péter Catholic University
- BrainVisionCenter
- Computational Systems Neuroscience Lab, Wigner Research Centre for Physics
- Department of Mathematical Geometry, Institute of Mathematics, Budapest University of Technology and Economics
| | | | - Balázs Chiovini
- Laboratory of 3D functional network and dendritic imaging, Institute of Experimental Medicine
| | - Gergely Szalay
- Laboratory of 3D functional network and dendritic imaging, Institute of Experimental Medicine
| | - Gergely Katona
- MTA-PPKE ITK-NAP B – 2p Measurement Technology Group, The Faculty of Information Technology, Pázmány Péter Catholic University
| | - Adam Kepecs
- Cold Spring Harbor Laboratory
- Departments of Neuroscience and Psychiatry, Washington University School of Medicine
| | - Balázs Rózsa
- Laboratory of 3D functional network and dendritic imaging, Institute of Experimental Medicine
- BrainVisionCenter
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9
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Sharp-wave ripple doublets induce complex dendritic spikes in parvalbumin interneurons in vivo. Nat Commun 2022; 13:6715. [PMID: 36344570 PMCID: PMC9640570 DOI: 10.1038/s41467-022-34520-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2021] [Accepted: 10/25/2022] [Indexed: 11/09/2022] Open
Abstract
Neuronal plasticity has been shown to be causally linked to coincidence detection through dendritic spikes (dSpikes). We demonstrate the existence of SPW-R-associated, branch-specific, local dSpikes and their computational role in basal dendrites of hippocampal PV+ interneurons in awake animals. To measure the entire dendritic arbor of long thin dendrites during SPW-Rs, we used fast 3D acousto-optical imaging through an eccentric deep-brain adapter and ipsilateral local field potential recording. The regenerative calcium spike started at variable, NMDA-AMPA-dependent, hot spots and propagated in both direction with a high amplitude beyond a critical distance threshold (~150 µm) involving voltage-gated calcium channels. A supralinear dendritic summation emerged during SPW-R doublets when two successive SPW-R events coincide within a short temporal window (~150 ms), e.g., during more complex association tasks, and generated large dSpikes with an about 2.5-3-fold amplitude increase which propagated down to the soma. Our results suggest that these doublet-associated dSpikes can work as a dendritic-level temporal and spatial coincidence detector during SPW-R-related network computation in awake mice.
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10
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Tuljak M, Lajevec D, Štanc R, Zemljič Jokhadar Š, Derganc J. Low-cost programable stroboscopic illumination with sub-microsecond pulses for high-throughput microfluidic applications. HARDWAREX 2022; 12:e00367. [PMID: 36238528 PMCID: PMC9552099 DOI: 10.1016/j.ohx.2022.e00367] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/13/2022] [Revised: 09/23/2022] [Accepted: 10/02/2022] [Indexed: 06/16/2023]
Abstract
To visualize fast-moving objects in microfluidic applications, the image acquisition time must be on the order of a microsecond or less. Commercial imaging systems capable of such short exposure times may be too expensive for many research laboratories. We have therefore developed a low-cost stroboscopic illumination for transmitted-light microscopy based on a high-power LED that can be coupled to a standard industrial camera and provides exposure times on the order of 500 ns. The system is designed to be easily mounted on a standard condenser of an inverted microscope. The illumination is controlled by a fast Arduino-compatible Teensy® 4.0 development board, and the illumination parameters can be set from a PC via a graphical user interface written in Python. The system has been successfully used for high-throughput cell phenotyping using deformability cytometry on a Nikon TE2000 microscope, as well as for droplet microfluidic on an old Olympus inverted microscope.
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Affiliation(s)
- Marko Tuljak
- Institute of Biophysics, Faculty of Medicine, University of Ljubljana, Vrazov trg 2, 1000 Ljubljana, Slovenia
| | - David Lajevec
- Institute of Biophysics, Faculty of Medicine, University of Ljubljana, Vrazov trg 2, 1000 Ljubljana, Slovenia
| | - Rok Štanc
- Institute of Biophysics, Faculty of Medicine, University of Ljubljana, Vrazov trg 2, 1000 Ljubljana, Slovenia
| | - Špela Zemljič Jokhadar
- Institute of Biophysics, Faculty of Medicine, University of Ljubljana, Vrazov trg 2, 1000 Ljubljana, Slovenia
| | - Jure Derganc
- Institute of Biophysics, Faculty of Medicine, University of Ljubljana, Vrazov trg 2, 1000 Ljubljana, Slovenia
- Chair of Microprocess Engineering and Technology—COMPETE, University of Ljubljana, Večna Pot 113, 1000 Ljubljana, Slovenia
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11
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Skoven CS, Tomasevic L, Kvitsiani D, Pakkenberg B, Dyrby TB, Siebner HR. Dose-response relationship between the variables of unilateral optogenetic stimulation and transcallosal evoked responses in rat motor cortex. Front Neurosci 2022; 16:968839. [PMID: 36213739 PMCID: PMC9539969 DOI: 10.3389/fnins.2022.968839] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2022] [Accepted: 08/19/2022] [Indexed: 11/17/2022] Open
Abstract
Efficient interhemispheric integration of neural activity between left and right primary motor cortex (M1) is critical for inter-limb motor control. We employed optogenetic stimulation to establish a framework for probing transcallosal M1–M1 interactions in rats. We performed optogenetic stimulation of excitatory neurons in right M1 of male Sprague-Dawley rats. We recorded the transcallosal evoked potential in contralateral left M1 via chronically implanted electrodes. Recordings were performed under anesthesia combination of dexmedetomidine and a low concentration of isoflurane. We systematically varied the stimulation intensity and duration to characterize the relationship between stimulation parameters in right M1 and the characteristics of the evoked intracortical potentials in left M1. Optogenetic stimulation of right M1 consistently evoked a transcallosal response in left M1 with a consistent negative peak (N1) that sometimes was preceded by a smaller positive peak (P1). Higher stimulation intensity or longer stimulation duration gradually increased N1 amplitude and reduced N1 variability across trials. A combination of stimulation intensities of 5–10 mW with stimulus durations of 1–10 ms were generally sufficient to elicit a robust transcallosal response in most animal, with our optic fiber setup. Optogenetically stimulated excitatory neurons in M1 can reliably evoke a transcallosal response in anesthetized rats. Characterizing the relationship between “stimulation dose” and “response magnitude” (i.e., the gain function) of transcallosal M1-to-M1 excitatory connections can be used to optimize the variables of optogenetic stimulation and ensure stimulation efficacy.
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Affiliation(s)
- Christian Stald Skoven
- Danish Research Centre for Magnetic Resonance, Centre for Functional and Diagnostic Imaging and Research, Copenhagen University Hospital Amager and Hvidovre, Copenhagen, Denmark
- Center for Functional Integrative Neuroscience, Aarhus University (AU), Aarhus, Denmark
- *Correspondence: Christian Stald Skoven,
| | - Leo Tomasevic
- Danish Research Centre for Magnetic Resonance, Centre for Functional and Diagnostic Imaging and Research, Copenhagen University Hospital Amager and Hvidovre, Copenhagen, Denmark
| | - Duda Kvitsiani
- Department of Molecular Biology and Genetics, Danish Research Institute of Translational Neuroscience, Aarhus University, Aarhus, Denmark
| | - Bente Pakkenberg
- Research Laboratory for Stereology and Neuroscience, Copenhagen University Hospital Bispebjerg and Frederiksberg, Copenhagen, Denmark
- Department of Clinical Medicine, Faculty of Medical and Health Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Tim Bjørn Dyrby
- Danish Research Centre for Magnetic Resonance, Centre for Functional and Diagnostic Imaging and Research, Copenhagen University Hospital Amager and Hvidovre, Copenhagen, Denmark
- Department of Applied Mathematics and Computer Science, Technical University of Denmark, Kongens Lyngby, Denmark
| | - Hartwig Roman Siebner
- Danish Research Centre for Magnetic Resonance, Centre for Functional and Diagnostic Imaging and Research, Copenhagen University Hospital Amager and Hvidovre, Copenhagen, Denmark
- Department of Clinical Medicine, Faculty of Medical and Health Sciences, University of Copenhagen, Copenhagen, Denmark
- Department of Neurology, Copenhagen University Hospital Bispebjerg and Frederiksberg, Copenhagen, Denmark
- Hartwig Roman Siebner,
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12
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Hegedüs P, Velencei A, Belval CHD, Heckenast J, Hangya B. Training protocol for probabilistic Pavlovian conditioning in mice using an open-source head-fixed setup. STAR Protoc 2021; 2:100795. [PMID: 34522902 PMCID: PMC8424585 DOI: 10.1016/j.xpro.2021.100795] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
High throughput, temporally controlled, reproducible quantitative behavioral assays are important for understanding the neural mechanisms underlying behavior. Here, we provide a step-by-step training protocol for a probabilistic Pavlovian conditioning task, where two auditory cues predict probabilistic outcomes with different contingencies. This protocol allows us to study the differential behavioral and neuronal correlates of expected and surprising outcomes. It has been tested in combination with chronic in vivo electrophysiological recordings and optogenetic manipulations in ChAT-Cre and PV-Cre mouse lines. For complete details on the use and execution of this protocol, please refer to Hegedüs et al. (2021). We provide a training protocol for a probabilistic Pavlovian conditioning task in mice Two auditory cues predict probabilistic outcomes with different contingencies Possible to combine with chronic in vivo electrophysiology and optogenetics Ideal for testing behavioral and neural correlates of expected and surprising outcomes
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Affiliation(s)
- Panna Hegedüs
- Lendület Laboratory of Systems Neuroscience, Institute of Experimental Medicine, Budapest, Hungary.,János Szentágothai Doctoral School of Neurosciences, Semmelweis University, Budapest, Hungary
| | - Anna Velencei
- Lendület Laboratory of Systems Neuroscience, Institute of Experimental Medicine, Budapest, Hungary
| | - Claire-Hélène de Belval
- Lendület Laboratory of Systems Neuroscience, Institute of Experimental Medicine, Budapest, Hungary.,Interdisciplinary Masters' in Life Sciences, Ecole Normale Supérieure, Paris, France
| | - Julia Heckenast
- Lendület Laboratory of Systems Neuroscience, Institute of Experimental Medicine, Budapest, Hungary
| | - Balázs Hangya
- Lendület Laboratory of Systems Neuroscience, Institute of Experimental Medicine, Budapest, Hungary
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13
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Contribution of non-sensory neurons in visual cortical areas to visually guided decisions in the rat. Curr Biol 2021; 31:2757-2769.e6. [DOI: 10.1016/j.cub.2021.03.099] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2020] [Revised: 03/15/2021] [Accepted: 03/31/2021] [Indexed: 01/18/2023]
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14
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Zhang WW, Li RR, Zhang J, Yan J, Zhang QH, Hu ZA, Hu B, Yao ZX, Chen H. Hippocampal Interneurons are Required for Trace Eyeblink Conditioning in Mice. Neurosci Bull 2021; 37:1147-1159. [PMID: 33991316 PMCID: PMC8353031 DOI: 10.1007/s12264-021-00700-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2020] [Accepted: 12/22/2020] [Indexed: 12/29/2022] Open
Abstract
While the hippocampus has been implicated in supporting the association among time-separated events, the underlying cellular mechanisms have not been fully clarified. Here, we combined in vivo multi-channel recording and optogenetics to investigate the activity of hippocampal interneurons in freely-moving mice performing a trace eyeblink conditioning (tEBC) task. We found that the hippocampal interneurons exhibited conditioned stimulus (CS)-evoked sustained activity, which predicted the performance of conditioned eyeblink responses (CRs) in the early acquisition of the tEBC. Consistent with this, greater proportions of hippocampal pyramidal cells showed CS-evoked decreased activity in the early acquisition of the tEBC. Moreover, optogenetic suppression of the sustained activity in hippocampal interneurons severely impaired acquisition of the tEBC. In contrast, suppression of the sustained activity of hippocampal interneurons had no effect on the performance of well-learned CRs. Our findings highlight the role of hippocampal interneurons in the tEBC, and point to a potential cellular mechanism subserving associative learning.
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Affiliation(s)
- Wei-Wei Zhang
- Department of Physiology, College of Basic Medical Sciences, Army Medical University, Chongqing, 400038, China
| | - Rong-Rong Li
- Department of Physiology, College of Basic Medical Sciences, Army Medical University, Chongqing, 400038, China
| | - Jie Zhang
- Department of Physiology, College of Basic Medical Sciences, Army Medical University, Chongqing, 400038, China
| | - Jie Yan
- Department of Physiology, College of Basic Medical Sciences, Army Medical University, Chongqing, 400038, China
| | - Qian-Hui Zhang
- Department of Foreign Language, College of Basic Medical Sciences, Army Medical University, Chongqing, 400038, China
| | - Zhi-An Hu
- Department of Physiology, College of Basic Medical Sciences, Army Medical University, Chongqing, 400038, China
| | - Bo Hu
- Department of Physiology, College of Basic Medical Sciences, Army Medical University, Chongqing, 400038, China. .,Brain and Intelligence Research Key Laboratory of Chongqing Education Commission, Army Medical University, Chongqing, 400038, China.
| | - Zhong-Xiang Yao
- Department of Physiology, College of Basic Medical Sciences, Army Medical University, Chongqing, 400038, China.
| | - Hao Chen
- Experimental Center of Basic Medicine, College of Basic Medical Sciences, Army Medical University, Chongqing, 400038, China.
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15
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Automated Functional Screening for Modulators of Optogenetically Activated Neural Responses in Living Organisms. Methods Mol Biol 2021. [PMID: 32865748 DOI: 10.1007/978-1-0716-0830-2_14] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
Abstract
All-optical methods of probing in vivo brain function are advantageous for their compatibility with automated microscopy and fast spatial targeting of neural circuit excitation and response. Recent advances in optogenetic technologies allow simultaneous light activation of specific neurons and optical readout of neural activity via fluorescent calcium reporters, providing an attractive opportunity for high-throughput screening assays that directly assess dynamic neural function in vivo. Here we describe a method to automatically record optogenetically activated neural responses in living, hydrogel-embedded organisms over many hours in a multiwell plate format. This method is suitable for screening the neural effects of hundreds of chemical compounds and assessing the time course of bioactivity over 12 h or more. As examples, we show the suppression of neural responses over time with various concentrations of two voltage-gated calcium channel blockers and a full-plate screen of 320 chemicals with positive and negative controls in a single experiment.
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16
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Bale MR, Bitzidou M, Giusto E, Kinghorn P, Maravall M. Sequence Learning Induces Selectivity to Multiple Task Parameters in Mouse Somatosensory Cortex. Curr Biol 2021; 31:473-485.e5. [PMID: 33186553 PMCID: PMC7883307 DOI: 10.1016/j.cub.2020.10.059] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2020] [Revised: 09/01/2020] [Accepted: 10/20/2020] [Indexed: 11/20/2022]
Abstract
Sequential temporal ordering and patterning are key features of natural signals, used by the brain to decode stimuli and perceive them as sensory objects. To explore how cortical neuronal activity underpins sequence discrimination, we developed a task in which mice distinguished between tactile "word" sequences constructed from distinct vibrations delivered to the whiskers, assembled in different orders. Animals licked to report the presence of the target sequence. Mice could respond to the earliest possible cues allowing discrimination, effectively solving the task as a "detection of change" problem, but enhanced their performance when responding later. Optogenetic inactivation showed that the somatosensory cortex was necessary for sequence discrimination. Two-photon imaging in layer 2/3 of the primary somatosensory "barrel" cortex (S1bf) revealed that, in well-trained animals, neurons had heterogeneous selectivity to multiple task variables including not just sensory input but also the animal's action decision and the trial outcome (presence or absence of the predicted reward). Many neurons were activated preceding goal-directed licking, thus reflecting the animal's learned action in response to the target sequence; these neurons were found as soon as mice learned to associate the rewarded sequence with licking. In contrast, learning evoked smaller changes in sensory response tuning: neurons responding to stimulus features were found in naive mice, and training did not generate neurons with enhanced temporal integration or categorical responses. Therefore, in S1bf, sequence learning results in neurons whose activity reflects the learned association between target sequence and licking rather than a refined representation of sensory features.
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Affiliation(s)
- Michael R Bale
- Sussex Neuroscience, School of Life Sciences, University of Sussex, Brighton BN1 9QG, UK
| | - Malamati Bitzidou
- Sussex Neuroscience, School of Life Sciences, University of Sussex, Brighton BN1 9QG, UK
| | - Elena Giusto
- Sussex Neuroscience, School of Life Sciences, University of Sussex, Brighton BN1 9QG, UK
| | - Paul Kinghorn
- Sussex Neuroscience, School of Life Sciences, University of Sussex, Brighton BN1 9QG, UK
| | - Miguel Maravall
- Sussex Neuroscience, School of Life Sciences, University of Sussex, Brighton BN1 9QG, UK.
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17
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Zhong Z, Sun K, Karaman MM, Zhou XJ. Magnetic resonance imaging with submillisecond temporal resolution. Magn Reson Med 2020; 85:2434-2444. [PMID: 33252784 DOI: 10.1002/mrm.28588] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2020] [Revised: 09/20/2020] [Accepted: 10/17/2020] [Indexed: 11/10/2022]
Abstract
PURPOSE To demonstrate an MRI technique-Submillisecond Periodic Event Encoded Dynamic Imaging (SPEEDI)-for capturing cyclic dynamic events with submillisecond temporal resolution. METHODS The SPEEDI technique is based on an FID or an echo signal in which each time point in the signal is used to sample a distinct k-space raster, followed by repeated FIDs or echoes to produce the remaining k-space data in each k-space raster. All acquisitions are synchronized with a cyclic event, resulting in a set of time-resolved images of the cyclic event with a temporal resolution determined by the dwell time. In SPEEDI, spatial encoding is accomplished by phase encoding. The SPEEDI technique was demonstrated in two experiments at 3 T to (1) visualize fast-changing electric currents that mimicked the waveform of an action potential, and (2) characterize rapidly decaying eddy currents in an MRI system, with a temporal resolution of 0.2 ms and 0.4 ms, respectively. In both experiments, compressed sensing was incorporated to reduce the scan times. Phase difference maps related to the dynamics of electric currents or eddy currents were then obtained. RESULTS In the first experiment, time-resolved phase maps resulting from the action potential-mimicking current waveform were successfully obtained and agreed well with theoretical calculations (normalized RMS error = 0.07). In the second experiment, spatially resolved eddy current phase maps revealed time constants (27.1 ± 0.2 ms, 41.1 ± 3.5 ms, and 34.8 ± 0.7 ms) that matched well with those obtained from an established method using point sources (26.4 ms, 41.2 ms and 34.8 ms). For both experiments, phase maps from fully sampled and compressed-sensing-accelerated k-space data exhibited a high structural similarity (> 0.8) despite a two-fold to three-fold acceleration. CONCLUSIONS We have illustrated that SPEEDI can provide submillisecond temporal resolution. This capability will likely lead to future exploration of ultrafast, cyclic biomedical processes using MRI.
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Affiliation(s)
- Zheng Zhong
- Center for Magnetic Resonance Research, University of Illinois at Chicago, Chicago, Illinois, USA.,Department of Bioengineering, University of Illinois at Chicago, Chicago, Illinois, USA
| | - Kaibao Sun
- Center for Magnetic Resonance Research, University of Illinois at Chicago, Chicago, Illinois, USA
| | - M Muge Karaman
- Center for Magnetic Resonance Research, University of Illinois at Chicago, Chicago, Illinois, USA.,Department of Bioengineering, University of Illinois at Chicago, Chicago, Illinois, USA
| | - Xiaohong Joe Zhou
- Center for Magnetic Resonance Research, University of Illinois at Chicago, Chicago, Illinois, USA.,Department of Bioengineering, University of Illinois at Chicago, Chicago, Illinois, USA.,Department of Radiology, University of Illinois at Chicago, Chicago, Illinois, USA.,Department of Neurosurgery, University of Illinois at Chicago, Chicago, Illinois, USA
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18
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Harun R, Jun E, Park HH, Ganupuru P, Goldring AB, Hanks TD. Timescales of Evidence Evaluation for Decision Making and Associated Confidence Judgments Are Adapted to Task Demands. Front Neurosci 2020; 14:826. [PMID: 32903672 PMCID: PMC7438826 DOI: 10.3389/fnins.2020.00826] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2020] [Accepted: 07/15/2020] [Indexed: 01/29/2023] Open
Abstract
Decision making often involves choosing actions based on relevant evidence. This can benefit from focussing evidence evaluation on the timescale of greatest relevance based on the situation. Here, we use an auditory change detection task to determine how people adjust their timescale of evidence evaluation depending on task demands for detecting changes in their environment and assessing their internal confidence in those decisions. We confirm previous results that people adopt shorter timescales of evidence evaluation for detecting changes in contexts with shorter signal durations, while bolstering those results with model-free analyses not previously used and extending the results to the auditory domain. We also extend these results to show that in contexts with shorter signal durations, people also adopt correspondingly shorter timescales of evidence evaluation for assessing confidence in their decision about detecting a change. These results provide important insights into adaptability and flexible control of evidence evaluation for decision making.
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Affiliation(s)
- Rashed Harun
- Department of Neurology and Center for Neuroscience, University of California, Davis, Davis, CA, United States
| | - Elizabeth Jun
- Department of Neurology and Center for Neuroscience, University of California, Davis, Davis, CA, United States
| | - Heui Hye Park
- Department of Neurology and Center for Neuroscience, University of California, Davis, Davis, CA, United States
| | - Preetham Ganupuru
- Department of Neurology and Center for Neuroscience, University of California, Davis, Davis, CA, United States
| | - Adam B Goldring
- Department of Neurology and Center for Neuroscience, University of California, Davis, Davis, CA, United States
| | - Timothy D Hanks
- Department of Neurology and Center for Neuroscience, University of California, Davis, Davis, CA, United States
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19
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Dynamic coordination of the perirhinal cortical neurons supports coherent representations between task epochs. Commun Biol 2020; 3:406. [PMID: 32733065 PMCID: PMC7393175 DOI: 10.1038/s42003-020-01129-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2020] [Accepted: 07/08/2020] [Indexed: 01/10/2023] Open
Abstract
Cortical neurons show distinct firing patterns across multiple task epochs characterized by different computations. Recent studies suggest that such distinct patterns underlie dynamic population code achieving computational flexibility, whereas neurons in some cortical areas often show coherent firing patterns across epochs. To understand how coherent single-neuron code contributes to dynamic population code, we analyzed neural responses in the rat perirhinal cortex (PRC) during cue and reward epochs of a two-alternative forced-choice task. We found that the PRC neurons often encoded the opposite choice directions between those epochs. By using principal component analysis as a population-level analysis, we identified neural subspaces associated with each epoch, which reflected coordination across the neurons. The cue and reward epochs shared neural dimensions where the choice directions were consistently discriminated. Interestingly, those dimensions were supported by dynamically changing contributions of the individual neurons. These results demonstrated heterogeneity of coherent single-neuron representations in their contributions to population code.
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20
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Masset P, Ott T, Lak A, Hirokawa J, Kepecs A. Behavior- and Modality-General Representation of Confidence in Orbitofrontal Cortex. Cell 2020; 182:112-126.e18. [PMID: 32504542 DOI: 10.1016/j.cell.2020.05.022] [Citation(s) in RCA: 42] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2019] [Revised: 02/27/2020] [Accepted: 05/11/2020] [Indexed: 02/06/2023]
Abstract
Every decision we make is accompanied by a sense of confidence about its likely outcome. This sense informs subsequent behavior, such as investing more-whether time, effort, or money-when reward is more certain. A neural representation of confidence should originate from a statistical computation and predict confidence-guided behavior. An additional requirement for confidence representations to support metacognition is abstraction: they should emerge irrespective of the source of information and inform multiple confidence-guided behaviors. It is unknown whether neural confidence signals meet these criteria. Here, we show that single orbitofrontal cortex neurons in rats encode statistical decision confidence irrespective of the sensory modality, olfactory or auditory, used to make a choice. The activity of these neurons also predicts two confidence-guided behaviors: trial-by-trial time investment and cross-trial choice strategy updating. Orbitofrontal cortex thus represents decision confidence consistent with a metacognitive process that is useful for mediating confidence-guided economic decisions.
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Affiliation(s)
- Paul Masset
- Cold Spring Harbor Laboratory, 1 Bungtown Road, Cold Spring Harbor, NY 11724, USA; Watson School of Biological Sciences, 1 Bungtown Road, Cold Spring Harbor, NY 11724, USA
| | - Torben Ott
- Cold Spring Harbor Laboratory, 1 Bungtown Road, Cold Spring Harbor, NY 11724, USA; Department of Neuroscience and Department of Psychiatry, Washington University in St. Louis, St. Louis, MO 63110, USA
| | - Armin Lak
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford OX1 3PT, UK
| | - Junya Hirokawa
- Cold Spring Harbor Laboratory, 1 Bungtown Road, Cold Spring Harbor, NY 11724, USA
| | - Adam Kepecs
- Cold Spring Harbor Laboratory, 1 Bungtown Road, Cold Spring Harbor, NY 11724, USA; Watson School of Biological Sciences, 1 Bungtown Road, Cold Spring Harbor, NY 11724, USA; Department of Neuroscience and Department of Psychiatry, Washington University in St. Louis, St. Louis, MO 63110, USA.
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21
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Mottaghi S, Afshari N, Buchholz O, Liebana S, Hofmann UG. Modular Current Stimulation System for Pre-clinical Studies. Front Neurosci 2020; 14:408. [PMID: 32425752 PMCID: PMC7203490 DOI: 10.3389/fnins.2020.00408] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2020] [Accepted: 04/03/2020] [Indexed: 11/13/2022] Open
Abstract
Electric stimulators with precise and reliable outputs are an indispensable part of electrophysiological research. From single cells to deep brain or neuromuscular tissue, there are diverse targets for electrical stimulation. Even though commercial systems are available, we state the need for a low-cost, high precision, functional, and modular (hardware, firmware, and software) current stimulation system with the capacity to generate stable and complex waveforms for pre-clinical research. The system presented in this study is a USB controlled 4-channel modular current stimulator that can be expanded and generate biphasic arbitrary waveforms with 16-bit resolution, high temporal precision (μs), and passive charge balancing: the NES STiM (Neuro Electronic Systems Stimulator). We present a detailed description of the system’s structural design, the controlling software, reliability test, and the pre-clinical studies [deep brain stimulation (DBS) in hemi-PD rat model] in which it was utilized. The NES STiM has been tested with MacOS and Windows operating systems. Interfaces to MATLAB source codes are provided. The system is inexpensive, relatively easy to build and can be assembled quickly. We hope that the NES STiM will be used in a wide variety of neurological applications such as Functional Electrical Stimulation (FES), DBS and closed loop neurophysiological research.
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Affiliation(s)
- Soheil Mottaghi
- Section for Neuroelectronic Systems, Department of Neurosurgery, Medical Center University of Freiburg, Freiburg, Germany.,Faculty of Medicine, University of Freiburg, Freiburg, Germany.,Technical Faculty, University of Freiburg, Freiburg, Germany
| | - Niloofar Afshari
- Section for Neuroelectronic Systems, Department of Neurosurgery, Medical Center University of Freiburg, Freiburg, Germany
| | - Oliver Buchholz
- Section for Neuroelectronic Systems, Department of Neurosurgery, Medical Center University of Freiburg, Freiburg, Germany
| | - Samuel Liebana
- Department of Engineering, University of Cambridge, Cambridge, United Kingdom
| | - Ulrich G Hofmann
- Section for Neuroelectronic Systems, Department of Neurosurgery, Medical Center University of Freiburg, Freiburg, Germany.,Faculty of Medicine, University of Freiburg, Freiburg, Germany.,Technical Faculty, University of Freiburg, Freiburg, Germany
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22
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Széll A, Martínez-Bellver S, Hegedüs P, Hangya B. OPETH: Open Source Solution for Real-Time Peri-Event Time Histogram Based on Open Ephys. Front Neuroinform 2020; 14:21. [PMID: 32508613 PMCID: PMC7251067 DOI: 10.3389/fninf.2020.00021] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2019] [Accepted: 04/17/2020] [Indexed: 12/22/2022] Open
Abstract
Single cell electrophysiology remains one of the most widely used approaches of systems neuroscience. Decisions made by the experimenter during electrophysiology recording largely determine recording quality, duration of the project and value of the collected data. Therefore, online feedback aiding these decisions can lower monetary and time investment, and substantially speed up projects as well as allow novel studies otherwise not possible due to prohibitively low throughput. Real-time feedback is especially important in studies that involve optogenetic cell type identification by enabling a systematic search for neurons of interest. However, such tools are scarce and limited to costly commercial systems with high degree of specialization, which hitherto prevented wide-ranging benefits for the community. To address this, we present an open-source tool that enables online feedback during electrophysiology experiments and provides a Python interface for the widely used Open Ephys open source data acquisition system. Specifically, our software allows flexible online visualization of spike alignment to external events, called the online peri-event time histogram (OPETH). These external events, conveyed by digital logic signals, may indicate photostimulation time stamps for in vivo optogenetic cell type identification or the times of behaviorally relevant events during in vivo behavioral neurophysiology experiments. Therefore, OPETH allows real-time identification of genetically defined neuron types or behaviorally responsive populations. By allowing "hunting" for neurons of interest, OPETH significantly reduces experiment time and thus increases the efficiency of experiments that combine in vivo electrophysiology with behavior or optogenetic tagging of neurons.
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Affiliation(s)
- András Széll
- Lendület Laboratory of Systems Neuroscience, Institute of Experimental Medicine, Budapest, Hungary
| | - Sergio Martínez-Bellver
- Lendület Laboratory of Systems Neuroscience, Institute of Experimental Medicine, Budapest, Hungary
- Laboratory of Neural Circuitry, Faculty of Medicine and Dentistry, University of Valencia, Valencia, Spain
| | - Panna Hegedüs
- Lendület Laboratory of Systems Neuroscience, Institute of Experimental Medicine, Budapest, Hungary
- János Szentágothai Doctoral School of Neurosciences, Semmelweis University, Budapest, Hungary
| | - Balázs Hangya
- Lendület Laboratory of Systems Neuroscience, Institute of Experimental Medicine, Budapest, Hungary
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23
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Edwards KA, Hoppa MB, Bosco G. The Photoconvertible Fluorescent Probe, CaMPARI, Labels Active Neurons in Freely-Moving Intact Adult Fruit Flies. Front Neural Circuits 2020; 14:22. [PMID: 32457580 PMCID: PMC7227398 DOI: 10.3389/fncir.2020.00022] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2020] [Accepted: 04/14/2020] [Indexed: 01/27/2023] Open
Abstract
Linking neural circuitry to behavior by mapping active neurons in vivo is a challenge. Both genetically encoded calcium indicators (GECIs) and intermediate early genes (IEGs) have been used to pinpoint active neurons during a stimulus or behavior but have drawbacks such as limiting the movement of the organism, requiring a priori knowledge of the active region or having poor temporal resolution. Calcium-modulated photoactivatable ratiometric integrator (CaMPARI) was engineered to overcome these spatial-temporal challenges. CaMPARI is a photoconvertible protein that only converts from green to red fluorescence in the presence of high calcium concentration and 405 nm light. This allows the experimenter to precisely mark active neurons within defined temporal windows. The photoconversion can then be quantified by taking the ratio of the red fluorescence to the green. CaMPARI promises the ability to trace active neurons during a specific stimulus; however, CaMPARI's uses in adult Drosophila have been limited to photoconversion during fly immobilization. Here, we demonstrate a method that allows photoconversion of multiple freely-moving intact adult flies during a stimulus. Flies were placed in a dish with filter paper wet with acetic acid (pH = 2) or neutralized acetic acid (pH = 7) and exposed to photoconvertible light (60 mW) for 30 min (500 ms on, 200 ms off). Immediately following photoconversion, whole flies were fixed and imaged by confocal microscopy. The red:green ratio was quantified for the DC4 glomerulus, a bundle of neurons expressing Ir64a, an ionotropic receptor that senses acids in the Drosophila antennal lobe. Flies exposed to acetic acid showed 1.3-fold greater photoconversion than flies exposed to neutralized acetic acid. This finding was recapitulated using a more physiological stimulus of apple cider vinegar. These results indicate that CaMPARI can be used to label neurons in intact, freely-moving adult flies and will be useful for identifying the circuitry underlying complex behaviors.
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Affiliation(s)
- Katie A. Edwards
- Department of Molecular and Systems Biology, Geisel School of Medicine, Dartmouth College, Hanover, NH, United States
| | - Michael B. Hoppa
- Department of Biological Sciences, Dartmouth College, Hanover, NH, United States
| | - Giovanni Bosco
- Department of Molecular and Systems Biology, Geisel School of Medicine, Dartmouth College, Hanover, NH, United States
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24
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Lak A, Hueske E, Hirokawa J, Masset P, Ott T, Urai AE, Donner TH, Carandini M, Tonegawa S, Uchida N, Kepecs A. Reinforcement biases subsequent perceptual decisions when confidence is low, a widespread behavioral phenomenon. eLife 2020; 9:e49834. [PMID: 32286227 PMCID: PMC7213979 DOI: 10.7554/elife.49834] [Citation(s) in RCA: 46] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2019] [Accepted: 04/09/2020] [Indexed: 11/13/2022] Open
Abstract
Learning from successes and failures often improves the quality of subsequent decisions. Past outcomes, however, should not influence purely perceptual decisions after task acquisition is complete since these are designed so that only sensory evidence determines the correct choice. Yet, numerous studies report that outcomes can bias perceptual decisions, causing spurious changes in choice behavior without improving accuracy. Here we show that the effects of reward on perceptual decisions are principled: past rewards bias future choices specifically when previous choice was difficult and hence decision confidence was low. We identified this phenomenon in six datasets from four laboratories, across mice, rats, and humans, and sensory modalities from olfaction and audition to vision. We show that this choice-updating strategy can be explained by reinforcement learning models incorporating statistical decision confidence into their teaching signals. Thus, reinforcement learning mechanisms are continually engaged to produce systematic adjustments of choices even in well-learned perceptual decisions in order to optimize behavior in an uncertain world.
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Affiliation(s)
- Armin Lak
- Department of Physiology, Anatomy and Genetics, University of OxfordOxfordUnited Kingdom
- UCL Institute of Ophthalmology, University College LondonLondonUnited Kingdom
| | - Emily Hueske
- Department of Molecular and Cellular Biology and Center for Brain Science, Harvard UniversityCambridgeUnited States
- RIKEN-MIT Laboratory at the Picower Institute for Learning and Memory at Department of Biology and Department of Brain and Cognitive Science, Massachusetts Institute of TechnologyCambridgeUnited States
- McGovern Institute for Brain Research at Department of Brain and Cognitive Sciences, Massachusetts Institute of TechnologyCambridgeUnited States
| | - Junya Hirokawa
- Cold Spring Harbor LaboratoryCold Spring HarborUnited States
- Graduate School of Brain Science, Doshisha University, KyotanabeKyotoJapan
| | - Paul Masset
- Department of Molecular and Cellular Biology and Center for Brain Science, Harvard UniversityCambridgeUnited States
- Cold Spring Harbor LaboratoryCold Spring HarborUnited States
- Watson School of Biological SciencesCold Spring HarborUnited States
| | - Torben Ott
- Cold Spring Harbor LaboratoryCold Spring HarborUnited States
- Departments of Neuroscience and Psychiatry, Washington University School of MedicineSt. LouisUnited States
| | - Anne E Urai
- Cold Spring Harbor LaboratoryCold Spring HarborUnited States
- Department of Neurophysiology, University Medical Center, Hamburg-EppendorfHamburgGermany
| | - Tobias H Donner
- Department of Neurophysiology, University Medical Center, Hamburg-EppendorfHamburgGermany
| | - Matteo Carandini
- UCL Institute of Ophthalmology, University College LondonLondonUnited Kingdom
| | - Susumu Tonegawa
- RIKEN-MIT Laboratory at the Picower Institute for Learning and Memory at Department of Biology and Department of Brain and Cognitive Science, Massachusetts Institute of TechnologyCambridgeUnited States
- Howard Hughes Medical Institute at Massachusetts Institute of TechnologyCambridgeUnited States
| | - Naoshige Uchida
- Department of Molecular and Cellular Biology and Center for Brain Science, Harvard UniversityCambridgeUnited States
| | - Adam Kepecs
- Cold Spring Harbor LaboratoryCold Spring HarborUnited States
- Departments of Neuroscience and Psychiatry, Washington University School of MedicineSt. LouisUnited States
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25
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Ojeda A, Buscher N, Balasubramani P, Maric V, Ramanathan D, Mishra J. SimBSI: An open-source Simulink library for developing closed-loop brain signal interfaces in animals and humans. Biomed Phys Eng Express 2020; 6:035023. [PMID: 33438668 PMCID: PMC10092292 DOI: 10.1088/2057-1976/ab6e20] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
OBJECTIVE A promising application of BCI technology is in the development of personalized therapies that can target neural circuits linked to mental or physical disabilities. Typical BCIs, however, offer limited value due to simplistic designs and poor understanding of the conditions being treated. Building BCIs on more solid grounds may require the characterization of the brain dynamics supporting cognition and behavior at multiple scales, from single-cell and local field potential (LFP) recordings in animals to non-invasive electroencephalography (EEG) in humans. Despite recent efforts, a unifying software framework to support closed-loop studies in both animals and humans is still lacking. The objective of this paper is to develop such a unifying neurotechnological software framework. APPROACH Here we develop the Simulink for Brain Signal Interfaces library (SimBSI). Simulink is a mature graphical programming environment within MATLAB that has gained traction for processing electrophysiological data. SimBSI adds to this ecosystem: 1) advanced human EEG source imaging, 2) cross-species multimodal data acquisition based on the Lab Streaming Layer library, and 3) a graphical experimental design platform. MAIN RESULTS We use several examples to demonstrate the capabilities of the library, ranging from simple signal processing, to online EEG source imaging, cognitive task design, and closed-loop neuromodulation. We further demonstrate the simplicity of developing a sophisticated experimental environment for rodents within this environment. SIGNIFICANCE With the SimBSI library we hope to aid BCI practitioners of dissimilar backgrounds in the development of, much needed, single and cross-species closed-loop neuroscientific experiments. These experiments may provide the necessary mechanistic data for BCIs to become effective therapeutic tools.
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Affiliation(s)
- Alejandro Ojeda
- Neural Engineering and Translation Labs, Department of Psychiatry, University of California San Diego, La Jolla , California, United States of America
| | - Nathalie Buscher
- Neural Engineering and Translation Labs, Department of Psychiatry, University of California San Diego, La Jolla , California, United States of America.,Mental Health, VA San Diego Medical Center, United States of America
| | - Pragathi Balasubramani
- Neural Engineering and Translation Labs, Department of Psychiatry, University of California San Diego, La Jolla , California, United States of America
| | - Vojislav Maric
- Neural Engineering and Translation Labs, Department of Psychiatry, University of California San Diego, La Jolla , California, United States of America
| | - Dhakshin Ramanathan
- Neural Engineering and Translation Labs, Department of Psychiatry, University of California San Diego, La Jolla , California, United States of America.,Mental Health, VA San Diego Medical Center, United States of America
| | - Jyoti Mishra
- Neural Engineering and Translation Labs, Department of Psychiatry, University of California San Diego, La Jolla , California, United States of America
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26
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Mohanty A, Li Q, Tadayon MA, Roberts SP, Bhatt GR, Shim E, Ji X, Cardenas J, Miller SA, Kepecs A, Lipson M. Reconfigurable nanophotonic silicon probes for sub-millisecond deep-brain optical stimulation. Nat Biomed Eng 2020; 4:223-231. [PMID: 32051578 DOI: 10.1038/s41551-020-0516-y] [Citation(s) in RCA: 51] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2018] [Accepted: 01/13/2020] [Indexed: 11/09/2022]
Abstract
The use of nanophotonics to rapidly and precisely reconfigure light beams for the optical stimulation of neurons in vivo has remained elusive. Here we report the design and fabrication of an implantable silicon-based probe that can switch and route multiple optical beams to stimulate identified sets of neurons across cortical layers and simultaneously record the produced spike patterns. Each switch in the device consists of a silicon nitride waveguide structure that can be rapidly (<20 μs) reconfigured by electrically tuning the phase of light. By using an eight-beam probe, we show in anaesthetized mice that small groups of single neurons can be independently stimulated to produce multineuron spike patterns at sub-millisecond precision. We also show that a probe integrating co-fabricated electrical recording sites can simultaneously optically stimulate and electrically measure deep-brain neural activity. The technology is scalable, and it allows for beam focusing and steering and for structured illumination via beam shaping. The high-bandwidth optical-stimulation capacity of the device might facilitate the probing of the spatiotemporal neural codes underlying behaviour.
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Affiliation(s)
- Aseema Mohanty
- Department of Electrical Engineering, Columbia University, New York, NY, USA.,School of Electrical and Computer Engineering, Cornell University, Ithaca, NY, USA
| | - Qian Li
- Cold Spring Harbor Laboratory, Cold Spring Harbor, New York, NY, USA.,Department of Neuroscience, Washington University in St. Louis, St. Louis, MO, USA
| | | | - Samantha P Roberts
- Department of Electrical Engineering, Columbia University, New York, NY, USA
| | - Gaurang R Bhatt
- Department of Electrical Engineering, Columbia University, New York, NY, USA
| | - Euijae Shim
- Department of Electrical Engineering, Columbia University, New York, NY, USA
| | - Xingchen Ji
- Department of Electrical Engineering, Columbia University, New York, NY, USA.,School of Electrical and Computer Engineering, Cornell University, Ithaca, NY, USA
| | - Jaime Cardenas
- Department of Electrical Engineering, Columbia University, New York, NY, USA.,Institute of Optics, University of Rochester, Rochester, NY, USA
| | - Steven A Miller
- Department of Electrical Engineering, Columbia University, New York, NY, USA
| | - Adam Kepecs
- Cold Spring Harbor Laboratory, Cold Spring Harbor, New York, NY, USA. .,Department of Neuroscience, Washington University in St. Louis, St. Louis, MO, USA. .,Department of Psychiatry, Washington University in St. Louis, St. Louis, MO, USA.
| | - Michal Lipson
- Department of Electrical Engineering, Columbia University, New York, NY, USA.
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27
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The pheromone darcin drives a circuit for innate and reinforced behaviours. Nature 2020; 578:137-141. [PMID: 31996852 DOI: 10.1038/s41586-020-1967-8] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2018] [Accepted: 12/12/2019] [Indexed: 12/19/2022]
Abstract
Organisms have evolved diverse behavioural strategies that enhance the likelihood of encountering and assessing mates1. Many species use pheromones to communicate information about the location, sexual and social status of potential partners2. In mice, the major urinary protein darcin-which is present in the urine of males-provides a component of a scent mark that elicits approach by females and drives learning3,4. Here we show that darcin elicits a complex and variable behavioural repertoire that consists of attraction, ultrasonic vocalization and urinary scent marking, and also serves as a reinforcer in learning paradigms. We identify a genetically determined circuit-extending from the accessory olfactory bulb to the posterior medial amygdala-that is necessary for all behavioural responses to darcin. Moreover, optical activation of darcin-responsive neurons in the medial amygdala induces both the innate and the conditioned behaviours elicited by the pheromone. These neurons define a topographically segregated population that expresses neuronal nitric oxide synthase. We suggest that this darcin-activated neural circuit integrates pheromonal information with internal state to elicit both variable innate behaviours and reinforced behaviours that may promote mate encounters and mate selection.
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28
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Frontal cortex neuron types categorically encode single decision variables. Nature 2019; 576:446-451. [DOI: 10.1038/s41586-019-1816-9] [Citation(s) in RCA: 86] [Impact Index Per Article: 17.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2017] [Accepted: 10/15/2019] [Indexed: 12/11/2022]
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29
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The rostroventral part of the thalamic reticular nucleus modulates fear extinction. Nat Commun 2019; 10:4637. [PMID: 31604913 PMCID: PMC6789150 DOI: 10.1038/s41467-019-12496-9] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2018] [Accepted: 09/03/2019] [Indexed: 02/02/2023] Open
Abstract
The thalamus has been implicated in fear extinction, yet the role of the thalamic reticular nucleus (TRN) in this process remains unclear. Here, in mice, we show that the rostroventral part of the TRN (TRNrv) is critically involved in the extinction of tone-dependent fear memory. Optogenetic excitation of TRNrv neurons during extinction learning dramatically facilitated, whereas the inhibition disrupted, the fear extinction. Single unit recordings demonstrated that TRNrv neurons selectively respond to conditioned stimuli but not to neutral stimuli. TRNrv neurons suppressed the spiking activity of the medial part of the dorsal midline thalamus (dMTm), and a blockade of this inhibitory pathway disrupted fear extinction. Finally, we found that the suppression of dMTm projections to the central amygdala promotes fear extinction, and TRNrv neurons have direct connections to this pathway. Our results uncover a previously unknown function of the TRN and delineate the neural circuit for thalamic control of fear memory. The precise role of the thalamic reticular nucleus in fear is not understood. Here, the authors report that the rostroventral part of the reticular nucleus is involved in the extinction of tone conditioned fear memory through its inhibitory projections to the dorsal midline thalamus.
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30
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Colville MJ, Park S, Zipfel WR, Paszek MJ. High-speed device synchronization in optical microscopy with an open-source hardware control platform. Sci Rep 2019; 9:12188. [PMID: 31434941 PMCID: PMC6704125 DOI: 10.1038/s41598-019-48455-z] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2019] [Accepted: 07/31/2019] [Indexed: 12/27/2022] Open
Abstract
Azimuthal beam scanning eliminates the uneven excitation field arising from laser interference in through-objective total internal reflection fluorescence (TIRF) microscopy. The same principle can be applied to scanning angle interference microscopy (SAIM), where precision control of the scanned laser beam presents unique technical challenges for the builders of custom azimuthal scanning microscopes. Accurate synchronization between the instrument computer, beam scanning system and excitation source is required to collect high quality data and minimize sample damage in SAIM acquisitions. Drawing inspiration from open-source prototyping systems, like the Arduino microcontroller boards, we developed a new instrument control platform to be affordable, easily programmed, and broadly useful, but with integrated, precision analog circuitry and optimized firmware routines tailored to advanced microscopy. We show how the integration of waveform generation, multiplexed analog outputs, and native hardware triggers into a single central hub provides a versatile platform for performing fast circle-scanning acquisitions, including azimuthal scanning SAIM and multiangle TIRF. We also demonstrate how the low communication latency of our hardware platform can reduce image intensity and reconstruction artifacts arising from synchronization errors produced by software control. Our complete platform, including hardware design, firmware, API, and software, is available online for community-based development and collaboration.
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Affiliation(s)
| | - Sangwoo Park
- Field of Biophysics, Cornell University, Ithaca, NY, 14853, USA
| | - Warren R Zipfel
- Field of Biophysics, Cornell University, Ithaca, NY, 14853, USA.,Nancy E. and Peter C. Meinig School of Biomedical Engineering, Cornell University, Ithaca, NY, 14853, USA.,Kavli Institute at Cornell for Nanoscale Science, Ithaca, NY, 14853, USA
| | - Matthew J Paszek
- Field of Biophysics, Cornell University, Ithaca, NY, 14853, USA. .,Robert Frederick Smith School of Chemical and Biomolecular Engineering, Cornell University, Ithaca, NY, 14853, USA. .,Field of Biomedical Engineering, Cornell University, Ithaca, NY, 14853, USA. .,Kavli Institute at Cornell for Nanoscale Science, Ithaca, NY, 14853, USA.
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31
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Monosynaptic Hippocampal-Prefrontal Projections Contribute to Spatial Memory Consolidation in Mice. J Neurosci 2019; 39:6978-6991. [PMID: 31285301 DOI: 10.1523/jneurosci.2158-18.2019] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2018] [Revised: 06/13/2019] [Accepted: 06/21/2019] [Indexed: 01/03/2023] Open
Abstract
Time locking between neocortical sleep slow oscillations, thalamo-cortical spindles, and hippocampal sharp-wave ripples has convincingly been shown to be a key element of systems consolidation. Here we investigate the role of monosynaptic projections from ventral/intermediate hippocampus to medial prefrontal cortex (mPFC) in sleep-dependent memory consolidation in male mice. Following acquisition learning in the Barnes maze, we optogenetically silenced the axonal terminals of hippocampal projections within mPFC during slow-wave sleep. This silencing during SWS selectively impaired recent but not remote memory in the absence of effects on error rate and escape latencies. Furthermore, it prevented the development of the most efficient search strategy and sleep spindle time-locking to slow oscillation. An increase in post-learning sleep sharp-wave ripple (SPWR) density and reduced time locking of learning-associated SPWR activity to sleep spindles may be a less specific response. Our results demonstrate that monosynaptic projections from hippocampus to mPFC contribute to sleep-dependent memory consolidation, potentially by affecting the temporal coupling of sleep-associated electrophysiological events.SIGNIFICANCE STATEMENT Convincing evidence supports the role of slow-wave sleep (SWS), and the relevance of close temporal coupling of neuronal activity between brain regions for systems consolidation. Less attention has been paid so far to the specific neuronal pathways underlying these processes. Here, we optogenetically silenced the direct monosynaptic projection from ventral/intermediate hippocampus (HC) to medial prefrontal cortex (mPFC) during SWS in male mice following repeated learning trials in a weakly aversive spatial task. Our results confirm the concept that the monosynaptic projection between HC and mPFC contributes to memory consolidation and support an important functional role of this pathway in shaping the temporal precision among sleep-associated electrophysiological events.
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32
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Ganupuru P, Goldring AB, Harun R, Hanks TD. Flexibility of Timescales of Evidence Evaluation for Decision Making. Curr Biol 2019; 29:2091-2097.e4. [PMID: 31178325 DOI: 10.1016/j.cub.2019.05.037] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2018] [Revised: 04/05/2019] [Accepted: 05/15/2019] [Indexed: 12/13/2022]
Abstract
To understand the neural mechanisms that support decision making, it is critical to characterize the timescale of evidence evaluation. Recent work has shown that subjects can adaptively adjust the timescale of evidence evaluation across blocks of trials depending on context [1]. However, it's currently unknown if adjustments to evidence evaluation occur online during deliberations based on a single stream of evidence. To examine this question, we employed a change-detection task in which subjects report their level of confidence in judging whether there has been a change in a stochastic auditory stimulus. Using a combination of psychophysical reverse correlation analyses and single-trial behavioral modeling, we compared the time period over which sensory information has leverage on detection report choices versus confidence. We demonstrate that the length of this period differs on separate sets of trials based on what's being reported. Surprisingly, confidence judgments on trials with no detection report are influenced by evidence occurring earlier than the time period of influence for detection reports. Our findings call into question models of decision formation involving static parameters that yield a singular timescale of evidence evaluation and instead suggest that the brain represents and utilizes multiple timescales of evidence evaluation during deliberation.
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Affiliation(s)
- Preetham Ganupuru
- Department of Neurology and Center for Neuroscience, University of California Davis, 1544 Newton Ct., Davis, CA 95618, USA
| | - Adam B Goldring
- Department of Neurology and Center for Neuroscience, University of California Davis, 1544 Newton Ct., Davis, CA 95618, USA
| | - Rashed Harun
- Department of Neurology and Center for Neuroscience, University of California Davis, 1544 Newton Ct., Davis, CA 95618, USA
| | - Timothy D Hanks
- Department of Neurology and Center for Neuroscience, University of California Davis, 1544 Newton Ct., Davis, CA 95618, USA.
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33
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Lee CR, Yonk AJ, Wiskerke J, Paradiso KG, Tepper JM, Margolis DJ. Opposing Influence of Sensory and Motor Cortical Input on Striatal Circuitry and Choice Behavior. Curr Biol 2019; 29:1313-1323.e5. [PMID: 30982651 DOI: 10.1016/j.cub.2019.03.028] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2018] [Revised: 02/04/2019] [Accepted: 03/14/2019] [Indexed: 12/21/2022]
Abstract
The striatum is the main input nucleus of the basal ganglia and is a key site of sensorimotor integration. While the striatum receives extensive excitatory afferents from the cerebral cortex, the influence of different cortical areas on striatal circuitry and behavior is unknown. Here, we find that corticostriatal inputs from whisker-related primary somatosensory (S1) and motor (M1) cortex differentially innervate projection neurons and interneurons in the dorsal striatum and exert opposing effects on sensory-guided behavior. Optogenetic stimulation of S1-corticostriatal afferents in ex vivo recordings produced larger postsynaptic potentials in striatal parvalbumin (PV)-expressing interneurons than D1- or D2-expressing spiny projection neurons (SPNs), an effect not observed for M1-corticostriatal afferents. Critically, in vivo optogenetic stimulation of S1-corticostriatal afferents produced task-specific behavioral inhibition, which was bidirectionally modulated by striatal PV interneurons. Optogenetic stimulation of M1 afferents produced the opposite behavioral effect. Thus, our results suggest opposing roles for sensory and motor cortex in behavioral choice via distinct influences on striatal circuitry.
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Affiliation(s)
- Christian R Lee
- Department of Cell Biology and Neuroscience, Rutgers, The State University of New Jersey, 604 Allison Road, Piscataway, NJ 08854, USA
| | - Alex J Yonk
- Department of Cell Biology and Neuroscience, Rutgers, The State University of New Jersey, 604 Allison Road, Piscataway, NJ 08854, USA
| | - Joost Wiskerke
- Department of Cell Biology and Neuroscience, Rutgers, The State University of New Jersey, 604 Allison Road, Piscataway, NJ 08854, USA
| | - Kenneth G Paradiso
- Department of Cell Biology and Neuroscience, Rutgers, The State University of New Jersey, 604 Allison Road, Piscataway, NJ 08854, USA
| | - James M Tepper
- Center for Molecular and Behavioral Neuroscience, Rutgers, The State University of New Jersey, 197 University Avenue, Newark, NJ 07102, USA
| | - David J Margolis
- Department of Cell Biology and Neuroscience, Rutgers, The State University of New Jersey, 604 Allison Road, Piscataway, NJ 08854, USA.
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34
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Romano M, Bucklin M, Gritton H, Mehrotra D, Kessel R, Han X. A Teensy microcontroller-based interface for optical imaging camera control during behavioral experiments. J Neurosci Methods 2019; 320:107-115. [PMID: 30946877 DOI: 10.1016/j.jneumeth.2019.03.019] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2018] [Revised: 03/11/2019] [Accepted: 03/30/2019] [Indexed: 11/28/2022]
Abstract
BACKGROUND Systems neuroscience experiments often require the integration of precisely timed data acquisition and behavioral monitoring. While specialized commercial systems have been designed to meet various needs of data acquisition and device control, they often fail to offer flexibility to interface with new instruments and variable behavioral experimental designs. NEW METHOD We developed a Teensy 3.2 microcontroller-based interface that is easily programmable, and offers high-speed, precisely timed behavioral data acquisition and digital and analog outputs for controlling sCMOS cameras and other devices. RESULTS We demonstrate the flexibility and the temporal precision of the Teensy interface in two experimental settings. In one example, we used the Teensy interface to record an animal's directional movement on a spherical treadmill, while delivering repeated digital pulses that can be used to control image acquisition from a sCMOS camera. In another example, we used the Teensy interface to deliver an auditory stimulus and a gentle eye puff at precise times in a trace conditioning eye blink behavioral paradigm, while delivering repeated digital pulses to trigger camera image acquisition. COMPARISON WITH EXISTING METHODS This interface allows high-speed and temporally precise digital data acquisition and device control during diverse behavioral experiments. CONCLUSION The Teensy interface, consisting of a Teensy 3.2 and custom software functions, provides a temporally precise, low-cost, and flexible platform to integrate sCMOS camera control into behavioral experiments.
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Affiliation(s)
- Michael Romano
- Boston University, Department of Biomedical Engineering, Boston, MA 02215, United States
| | - Mark Bucklin
- Boston University, Department of Biomedical Engineering, Boston, MA 02215, United States
| | - Howard Gritton
- Boston University, Department of Biomedical Engineering, Boston, MA 02215, United States
| | - Dev Mehrotra
- Boston University, Department of Biomedical Engineering, Boston, MA 02215, United States
| | - Robb Kessel
- Boston University, Department of Biomedical Engineering, Boston, MA 02215, United States
| | - Xue Han
- Boston University, Department of Biomedical Engineering, Boston, MA 02215, United States.
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35
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Lawton PF, Lee MD, Saunter CD, Girkin JM, McCarron JG, Wilson C. VasoTracker, a Low-Cost and Open Source Pressure Myograph System for Vascular Physiology. Front Physiol 2019; 10:99. [PMID: 30846942 PMCID: PMC6393368 DOI: 10.3389/fphys.2019.00099] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2018] [Accepted: 01/28/2019] [Indexed: 01/12/2023] Open
Abstract
Pressure myography, one of the most commonly used techniques in vascular research, measures the diameter of isolated, pressurized arteries to assess the functional activity of smooth muscle and endothelial cells. Despite the widespread adoption of this technique for assessing vascular function, there are only a small number of commercial systems and these are expensive. Here, we introduce a complete, open source pressure myograph system and analysis software, VasoTracker, that can be set-up for approximately 10% of the cost of commercial alternatives. We report on the development of VasoTracker and demonstrate its ability to assess various components of vascular reactivity. A unique feature of the VasoTracker platform is the publicly accessible website (http://www.vasotracker.com/) that documents how to assemble and use this affordable, adaptable, and expandable pressure myograph.
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Affiliation(s)
- Penelope F. Lawton
- Centre for Advanced Instrumentation, Biophysical Sciences Institute, Department of Physics, Durham University, Durham, United Kingdom
| | - Matthew D. Lee
- Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, Glasgow, United Kingdom
| | - Christopher D. Saunter
- Centre for Advanced Instrumentation, Biophysical Sciences Institute, Department of Physics, Durham University, Durham, United Kingdom
| | - John M. Girkin
- Centre for Advanced Instrumentation, Biophysical Sciences Institute, Department of Physics, Durham University, Durham, United Kingdom
| | - John G. McCarron
- Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, Glasgow, United Kingdom
| | - Calum Wilson
- Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, Glasgow, United Kingdom
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36
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A method for combining multiple-units readout of optogenetic control with natural stimulation-evoked eyeblink conditioning in freely-moving mice. Sci Rep 2019; 9:1857. [PMID: 30755637 PMCID: PMC6372581 DOI: 10.1038/s41598-018-37885-w] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2018] [Accepted: 12/12/2018] [Indexed: 01/20/2023] Open
Abstract
A growing pool of transgenic mice expressing Cre-recombinases, together with Cre-dependent opsin viruses, provide good tools to manipulate specific neural circuits related to eyeblink conditioning (EBC). However, currently available methods do not enable to get fast and precise readout of optogenetic control when the freely-moving mice are receiving EBC training. In the current study, we describe a laser diode (LD)-optical fiber (OF)-Tetrode assembly that allows for simultaneous multiple units recording and optical stimulation. Since the numbers of various cables that require to be connected are minimized, the LD-OF-Tetrode assembly can be combined with CS-US delivery apparatus for revealing the effects of optical stimulation on EBC in freely- moving mice. Moreover, this combination of techniques can be utilized to optogenetically intervene in hippocampal neuronal activities during the post-conditioning sleep in a closed-loop manner. This novel device thus enhances our ability to explore how specific neuronal assembly contributes to associative motor memory in vivo.
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37
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Hu X, Urhie O, Chang K, Hostetler R, Agmon A. A Novel Method for Training Mice in Visuo-Tactile 3-D Object Discrimination and Recognition. Front Behav Neurosci 2018; 12:274. [PMID: 30555307 PMCID: PMC6282041 DOI: 10.3389/fnbeh.2018.00274] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2018] [Accepted: 10/24/2018] [Indexed: 11/13/2022] Open
Abstract
Perceiving, recognizing and remembering 3-dimensional (3-D) objects encountered in the environment has a very high survival value; unsurprisingly, this ability is shared among many animal species, including humans. The psychological, psychophysical and neural basis for object perception, discrimination, recognition and memory has been extensively studied in humans, monkeys, pigeons and rodents, but is still far from understood. Nearly all 3-D object recognition studies in the rodent used the "novel object recognition" paradigm, which relies on innate rather than learned behavior; however, this procedure has several important limitations. Recently, investigators have begun to recognize the power of behavioral tasks learned through reinforcement training (operant conditioning) to reveal the sensorimotor and cognitive abilities of mice and to elucidate their underlying neural mechanisms. Here, we describe a novel method for training and testing mice in visual and tactile object discrimination, recognition and memory, and use it to begin to examine the underlying sensory basis for these cognitive capacities. A custom-designed Y maze was used to train mice to associate one of two 3-D objects with a food reward. Out of nine mice trained in two cohorts, seven reached performance criterion in about 20-35 daily sessions of 20 trials each. The learned association was retained, or rapidly re-acquired, after a 6 weeks hiatus in training. When tested under low light conditions, individual animals differed in the degree to which they used tactile or visual cues to identify the objects. Switching to total darkness resulted only in a transient dip in performance, as did subsequent trimming of all large whiskers (macrovibrissae). Additional removal of the small whiskers (microvibrissae) did not degrade performance, but transiently increased the time spent inspecting the object. This novel method can be combined in future studies with the large arsenal of genetic tools available in the mouse, to elucidate the neural basis of object perception, recognition and memory.
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Affiliation(s)
- Xian Hu
- Department of Neuroscience, West Virginia University School of Medicine, Morgantown, WV, United States
| | - Ogaga Urhie
- Department of Neuroscience, West Virginia University School of Medicine, Morgantown, WV, United States
| | - Kevin Chang
- Department of Neuroscience, West Virginia University School of Medicine, Morgantown, WV, United States
| | - Rachel Hostetler
- Department of Neuroscience, West Virginia University School of Medicine, Morgantown, WV, United States
| | - Ariel Agmon
- Department of Neuroscience, West Virginia University School of Medicine, Morgantown, WV, United States
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38
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Osako Y, Sakurai Y, Hirokawa J. Subjective decision threshold for accurate visual detection performance in rats. Sci Rep 2018; 8:9357. [PMID: 29921866 PMCID: PMC6008337 DOI: 10.1038/s41598-018-27696-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2018] [Accepted: 06/07/2018] [Indexed: 11/24/2022] Open
Abstract
The dissociation between a subjective-criterion performance and forced performance in a sensory detection can provide critical insights into the neural correlates of sensory awareness. Here, we established a behavioral task for rats to test their spatial-visual cue detection ability, using a two alternative choice task with and without a third choice option where animals get rewards only in the objective absence of a visual cue. In the trials without the third option, spatial choice accuracy decreased from near perfect to near chance levels as the visual cue brightness decreased. In contrast, with the third option, the rats exhibited >90% spatial choice accuracy regardless of the cue brightness. The rats chose the third choice option less frequently when the cue was brighter, suggesting that rats have a generalized strategy to make spatial choices only when their internal detection criterion is met. Interestingly, even when the animals chose the third option, they could still significantly and correctly choose the direction of the visual stimuli if they were forced. Our data suggest that the rats' variable detection performance with identical set of stimuli is derived from stochastic processing of visual signals with a certain internal detection threshold rather than general motivational threshold.
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Affiliation(s)
- Yuma Osako
- Laboratory of Neural Information, Graduate School of Brain Science, Doshisha University, 1-3 Tatara Miyakodani, Kyotanabe, Kyoto, 610-0394, Japan
| | - Yoshio Sakurai
- Laboratory of Neural Information, Graduate School of Brain Science, Doshisha University, 1-3 Tatara Miyakodani, Kyotanabe, Kyoto, 610-0394, Japan
| | - Junya Hirokawa
- Laboratory of Neural Information, Graduate School of Brain Science, Doshisha University, 1-3 Tatara Miyakodani, Kyotanabe, Kyoto, 610-0394, Japan.
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39
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Solari N, Sviatkó K, Laszlovszky T, Hegedüs P, Hangya B. Open Source Tools for Temporally Controlled Rodent Behavior Suitable for Electrophysiology and Optogenetic Manipulations. Front Syst Neurosci 2018; 12:18. [PMID: 29867383 PMCID: PMC5962774 DOI: 10.3389/fnsys.2018.00018] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2017] [Accepted: 04/25/2018] [Indexed: 12/11/2022] Open
Abstract
Understanding how the brain controls behavior requires observing and manipulating neural activity in awake behaving animals. Neuronal firing is timed at millisecond precision. Therefore, to decipher temporal coding, it is necessary to monitor and control animal behavior at the same level of temporal accuracy. However, it is technically challenging to deliver sensory stimuli and reinforcers as well as to read the behavioral responses they elicit with millisecond precision. Presently available commercial systems often excel in specific aspects of behavior control, but they do not provide a customizable environment allowing flexible experimental design while maintaining high standards for temporal control necessary for interpreting neuronal activity. Moreover, delay measurements of stimulus and reinforcement delivery are largely unavailable. We combined microcontroller-based behavior control with a sound delivery system for playing complex acoustic stimuli, fast solenoid valves for precisely timed reinforcement delivery and a custom-built sound attenuated chamber using high-end industrial insulation materials. Together this setup provides a physical environment to train head-fixed animals, enables calibrated sound stimuli and precisely timed fluid and air puff presentation as reinforcers. We provide latency measurements for stimulus and reinforcement delivery and an algorithm to perform such measurements on other behavior control systems. Combined with electrophysiology and optogenetic manipulations, the millisecond timing accuracy will help interpret temporally precise neural signals and behavioral changes. Additionally, since software and hardware provided here can be readily customized to achieve a large variety of paradigms, these solutions enable an unusually flexible design of rodent behavioral experiments.
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Affiliation(s)
- Nicola Solari
- Lendület Laboratory of Systems Neuroscience, Department of Cellular and Network Neurobiology, Institute of Experimental Medicine, Hungarian Academy of Sciences, Budapest, Hungary
| | - Katalin Sviatkó
- Lendület Laboratory of Systems Neuroscience, Department of Cellular and Network Neurobiology, Institute of Experimental Medicine, Hungarian Academy of Sciences, Budapest, Hungary.,János Szentágothai Doctoral School of Neurosciences, Semmelweis University, Budapest, Hungary
| | - Tamás Laszlovszky
- Lendület Laboratory of Systems Neuroscience, Department of Cellular and Network Neurobiology, Institute of Experimental Medicine, Hungarian Academy of Sciences, Budapest, Hungary.,János Szentágothai Doctoral School of Neurosciences, Semmelweis University, Budapest, Hungary
| | - Panna Hegedüs
- Lendület Laboratory of Systems Neuroscience, Department of Cellular and Network Neurobiology, Institute of Experimental Medicine, Hungarian Academy of Sciences, Budapest, Hungary
| | - Balázs Hangya
- Lendület Laboratory of Systems Neuroscience, Department of Cellular and Network Neurobiology, Institute of Experimental Medicine, Hungarian Academy of Sciences, Budapest, Hungary
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Sanders JI, Hangya B, Kepecs A. Signatures of a Statistical Computation in the Human Sense of Confidence. Neuron 2017; 90:499-506. [PMID: 27151640 DOI: 10.1016/j.neuron.2016.03.025] [Citation(s) in RCA: 120] [Impact Index Per Article: 17.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2015] [Revised: 01/05/2016] [Accepted: 03/23/2016] [Indexed: 11/29/2022]
Abstract
Human confidence judgments are thought to originate from metacognitive processes that provide a subjective assessment about one's beliefs. Alternatively, confidence is framed in mathematics as an objective statistical quantity: the probability that a chosen hypothesis is correct. Despite similar terminology, it remains unclear whether the subjective feeling of confidence is related to the objective, statistical computation of confidence. To address this, we collected confidence reports from humans performing perceptual and knowledge-based psychometric decision tasks. We observed two counterintuitive patterns relating confidence to choice and evidence: apparent overconfidence in choices based on uninformative evidence, and decreasing confidence with increasing evidence strength for erroneous choices. We show that these patterns lawfully arise from statistical confidence, and therefore occur even for perfectly calibrated confidence measures. Furthermore, statistical confidence quantitatively accounted for human confidence in our tasks without necessitating heuristic operations. Accordingly, we suggest that the human feeling of confidence originates from a mental computation of statistical confidence.
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Affiliation(s)
- Joshua I Sanders
- Cold Spring Harbor Laboratory, 1 Bungtown Road, Cold Spring Harbor, NY 11724, USA
| | - Balázs Hangya
- Cold Spring Harbor Laboratory, 1 Bungtown Road, Cold Spring Harbor, NY 11724, USA; Lendület Laboratory of Systems Neuroscience, Institute of Experimental Medicine, Hungarian Academy of Sciences, Budapest H-1083, Hungary
| | - Adam Kepecs
- Cold Spring Harbor Laboratory, 1 Bungtown Road, Cold Spring Harbor, NY 11724, USA.
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Black C, Voigts J, Agrawal U, Ladow M, Santoyo J, Moore C, Jones S. Open Ephys electroencephalography (Open Ephys + EEG): a modular, low-cost, open-source solution to human neural recording. J Neural Eng 2017; 14:035002. [PMID: 28266930 DOI: 10.1088/1741-2552/aa651f] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
OBJECTIVE Electroencephalography (EEG) offers a unique opportunity to study human neural activity non-invasively with millisecond resolution using minimal equipment in or outside of a lab setting. EEG can be combined with a number of techniques for closed-loop experiments, where external devices are driven by specific neural signals. However, reliable, commercially available EEG systems are expensive, often making them impractical for individual use and research development. Moreover, by design, a majority of these systems cannot be easily altered to the specification needed by the end user. We focused on mitigating these issues by implementing open-source tools to develop a new EEG platform to drive down research costs and promote collaboration and innovation. APPROACH Here, we present methods to expand the open-source electrophysiology system, Open Ephys (www.openephys.org), to include human EEG recordings. We describe the equipment and protocol necessary to interface various EEG caps with the Open Ephys acquisition board, and detail methods for processing data. We present applications of Open Ephys + EEG as a research tool and discuss how this innovative EEG technology lays a framework for improved closed-loop paradigms and novel brain-computer interface experiments. MAIN RESULTS The Open Ephys + EEG system can record reliable human EEG data, as well as human EMG data. A side-by-side comparison of eyes closed 8-14 Hz activity between the Open Ephys + EEG system and the Brainvision ActiCHamp EEG system showed similar average power and signal to noise. SIGNIFICANCE Open Ephys + EEG enables users to acquire high-quality human EEG data comparable to that of commercially available systems, while maintaining the price point and extensibility inherent to open-source systems.
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Affiliation(s)
- Christopher Black
- Center for Biomedical Engineering, Brown University, Providence, RI, United States of America
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