1
|
Varela C, Moreira JVS, Kocaoglu B, Dura-Bernal S, Ahmad S. A mechanism for deviance detection and contextual routing in the thalamus: a review and theoretical proposal. Front Neurosci 2024; 18:1359180. [PMID: 38486972 PMCID: PMC10938916 DOI: 10.3389/fnins.2024.1359180] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2023] [Accepted: 02/15/2024] [Indexed: 03/17/2024] Open
Abstract
Predictive processing theories conceptualize neocortical feedback as conveying expectations and contextual attention signals derived from internal cortical models, playing an essential role in the perception and interpretation of sensory information. However, few predictive processing frameworks outline concrete mechanistic roles for the corticothalamic (CT) feedback from layer 6 (L6), despite the fact that the number of CT axons is an order of magnitude greater than that of feedforward thalamocortical (TC) axons. Here we review the functional architecture of CT circuits and propose a mechanism through which L6 could regulate thalamic firing modes (burst, tonic) to detect unexpected inputs. Using simulations in a model of a TC cell, we show how the CT feedback could support prediction-based input discrimination in TC cells by promoting burst firing. This type of CT control can enable the thalamic circuit to implement spatial and context selective attention mechanisms. The proposed mechanism generates specific experimentally testable hypotheses. We suggest that the L6 CT feedback allows the thalamus to detect deviance from predictions of internal cortical models, thereby supporting contextual attention and routing operations, a far more powerful role than traditionally assumed.
Collapse
Affiliation(s)
- Carmen Varela
- Psychology Department, Florida Atlantic University, Boca Raton, FL, United States
| | - Joao V. S. Moreira
- Department of Physiology and Pharmacology, State University of New York (SUNY) Downstate Health Sciences University, Brooklyn, NY, United States
| | - Basak Kocaoglu
- Center for Connected Autonomy and Artificial Intelligence, Florida Atlantic University, Boca Raton, FL, United States
| | - Salvador Dura-Bernal
- Department of Physiology and Pharmacology, State University of New York (SUNY) Downstate Health Sciences University, Brooklyn, NY, United States
- Center for Biomedical Imaging and Neuromodulation, Nathan S. Kline Institute for Psychiatric Research, Orangeburg, NY, United States
| | | |
Collapse
|
2
|
Zimdahl JW, Rodger J, Mulders WHAM. Acoustic trauma increases inhibitory effects of amygdala electrical stimulation on thalamic neurons in a rat model. Hear Res 2023; 439:108891. [PMID: 37797476 DOI: 10.1016/j.heares.2023.108891] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/17/2023] [Revised: 08/25/2023] [Accepted: 09/20/2023] [Indexed: 10/07/2023]
Abstract
Acoustic trauma (AT) induced hearing loss elicits plasticity throughout the central auditory pathway, including at the level of the medial geniculate nucleus (MGN). Hearing loss also results in altered neuronal responses in the amygdala, which is involved in sensory gating at the level of the MGN. However, whether these altered responses in the amygdala affect sensory gating at the level of the MGN requires further evaluation. The current study aimed to investigate the effects of AT-induced hearing loss on the functional connectivity between the amygdala and the MGN. Male Sprague-Dawley rats were exposed to either sham (n = 5; no sound) or AT (n = 6; 16 kHz, 1 h, 124 dB SPL) under full anaesthesia. Auditory brainstem response (ABR) recordings were made to determine hearing thresholds. Two weeks post-exposure, extracellular recordings were used to assess the effect of electrical stimulation of the amygdala on tone-evoked (sham n = 22; AT n = 30) and spontaneous (sham n = 21; AT n = 29) activity of single neurons in the MGN. AT caused a large temporary and small permanent ABR threshold shift. Electrical stimulation of the amygdala induced differential effects (excitatory, inhibitory, or no effect) on both tone-evoked and spontaneous activity. In tone-evoked activity, electrical stimulation at 300 µA, maximum current, caused a significantly larger reduction in firing rate in AT animals compared to sham, due to an increase in the magnitude of inhibitory effects. In spontaneous activity, there was also a significantly larger magnitude of inhibitory effects following AT. The findings confirm that activation of the amygdala results in changes in MGN neuronal activity, and suggest the functional connectivity between the amygdala and the MGN is significantly altered following AT and subsequent hearing loss.
Collapse
Affiliation(s)
- Jack W Zimdahl
- School of Human Sciences, University of Western Australia, Crawley, WA 6009, Australia.
| | - Jennifer Rodger
- School of Human Sciences, University of Western Australia, Crawley, WA 6009, Australia; School of Biological Sciences, University of Western Australia, Crawley, WA 6009, Australia; Perron Institute for Neurological and Translational Research, Crawley, WA 6009, Australia
| | | |
Collapse
|
3
|
Brunelle DL, Llano DA. Role of auditory-somatosensory corticothalamic circuit integration in analgesia. Cell Calcium 2023; 111:102717. [PMID: 36931195 PMCID: PMC10755628 DOI: 10.1016/j.ceca.2023.102717] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2023] [Revised: 03/07/2023] [Accepted: 03/10/2023] [Indexed: 03/14/2023]
Abstract
Our sensory environment is permeated by a diverse array of auditory and somatosensory stimuli. The pairing of acoustic signals with concurrent or forthcoming tactile cues are abundant in everyday life and various survival contexts across species, thus deeming the ability to integrate sensory inputs arising from the combination of these stimuli as crucial. The corticothalamic system plays a critical role in orchestrating the construction, integration and distribution of the information extracted from these sensory modalities. In this mini-review, we provide a circuit-level description of the auditory corticothalamic pathway in conjunction with adjacent corticothalamic somatosensory projections. Although the extent of the functional interactions shared by these pathways is not entirely elucidated, activation of each of these systems appears to modulate sensory perception in the complementary domain. Several specific issues are reviewed. Under certain environmental noise conditions, the spectral information of a sound could induce modulations in nociception and even induce analgesia. We begin by discussing recent findings by Zhou et al. (2022) implicating the corticothalamic system in mediating sound-induced analgesia. Next, we describe relevant components of the corticothalamic pathway's functional organization. Additionally, we describe an emerging body of literature pointing to intrathalamic circuitry being optimal for controlling and selecting sensory signals across modalities, with the thalamic reticular nucleus being a candidate mechanism for directing cross-modal interactions. Finally, Ca2+ bursting in thalamic neurons evoked by the thalamic reticular nucleus is explored.
Collapse
Affiliation(s)
- Dimitri L Brunelle
- Neuroscience Program, University of Illinois at Urbana-Champaign, Urbana, IL 61801, United States of America
| | - Daniel A Llano
- Neuroscience Program, University of Illinois at Urbana-Champaign, Urbana, IL 61801, United States of America; Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, IL 61801, United States of America; Department of Molecular and Integrative Physiology, University of Illinois at Urbana-Champaign, Urbana, IL 61801, United States of America.
| |
Collapse
|
4
|
The role of thalamic nuclei in genetic generalized epilepsies. Epilepsy Res 2022; 182:106918. [DOI: 10.1016/j.eplepsyres.2022.106918] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2022] [Revised: 03/11/2022] [Accepted: 03/28/2022] [Indexed: 01/10/2023]
|
5
|
Kimura A. Sound Intensity-dependent Multiple Tonotopic Organizations and Complex Sub-threshold Alterations of Auditory Response Across Sound Frequencies in the Thalamic Reticular Nucleus. Neuroscience 2021; 475:10-51. [PMID: 34481912 DOI: 10.1016/j.neuroscience.2021.08.027] [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: 05/13/2021] [Revised: 08/23/2021] [Accepted: 08/25/2021] [Indexed: 11/17/2022]
Abstract
The thalamic reticular nucleus (TRN), a cluster of GABAergic cells, modulates sensory attention and perception through its inhibitory projections to thalamic nuclei. Cortical and thalamic topographic projections to the auditory TRN are thought to compose tonotopic organizations for modulation of thalamic auditory processing. The present study determined tonotopies in the TRN and examined interactions between probe and masker sounds to obtain insights into temporal processing associated with tonotopies. Experiments were performed on anesthetized rats, using juxta-cellular recording and labeling techniques. Following determination of tonotopies, effects of sub-threshold masker sound stimuli on onset and late responses evoked by a probe sound were examined. The main findings are as follows. Tonotopic organizations were recognized in cell location and axonal projection. Tonotopic gradients and their clarities were diverse, depending on sound intensity, response type and the tiers of the TRN. Robust alterations in response magnitude, latency and/or burst spiking took place following masker sounds in either a broad or narrow range of frequencies that were close or far away from the probe sound frequency. The majority of alterations were suppression recognizable up to 600 ms in the interval between masker and probe sounds, and directions of alteration differed depending on the interval. Finally, masker sound effects were associated with tonotopic organizations. These findings suggest that the auditory TRN is comprised of sound intensity-dependent multiple tonotopic organizations, which could configure temporal interactions of auditory information across sound frequencies and impose complex but spatiotemporally structured influences on thalamic auditory processing.
Collapse
Affiliation(s)
- Akihisa Kimura
- Department of Physiology, Wakayama Medical University, Wakayama Kimiidera 811-1, 641-8509, Japan.
| |
Collapse
|
6
|
Ibrahim BA, Murphy CA, Yudintsev G, Shinagawa Y, Banks MI, Llano DA. Corticothalamic gating of population auditory thalamocortical transmission in mouse. eLife 2021; 10:e56645. [PMID: 34028350 PMCID: PMC8186908 DOI: 10.7554/elife.56645] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2020] [Accepted: 05/23/2021] [Indexed: 12/12/2022] Open
Abstract
The mechanisms that govern thalamocortical transmission are poorly understood. Recent data have shown that sensory stimuli elicit activity in ensembles of cortical neurons that recapitulate stereotyped spontaneous activity patterns. Here, we elucidate a possible mechanism by which gating of patterned population cortical activity occurs. In this study, sensory-evoked all-or-none cortical population responses were observed in the mouse auditory cortex in vivo and similar stochastic cortical responses were observed in a colliculo-thalamocortical brain slice preparation. Cortical responses were associated with decreases in auditory thalamic synaptic inhibition and increases in thalamic synchrony. Silencing of corticothalamic neurons in layer 6 (but not layer 5) or the thalamic reticular nucleus linearized the cortical responses, suggesting that layer 6 corticothalamic feedback via the thalamic reticular nucleus was responsible for gating stochastic cortical population responses. These data implicate a corticothalamic-thalamic reticular nucleus circuit that modifies thalamic neuronal synchronization to recruit populations of cortical neurons for sensory representations.
Collapse
Affiliation(s)
- Baher A Ibrahim
- Department of Molecular and Integrative Physiology, University of IllinoisUrbana-ChampaignUnited States
- Beckman Institute for Advanced Science and Technology, University of IllinoisUrbana-ChampaignUnited States
| | - Caitlin A Murphy
- Department of Neuroscience, School of Medicine and Public Health, University of Wisconsin-MadisonWisconsin-MadisonUnited States
- Department of Anesthesiology, School of Medicine and Public Health, University of Wisconsin-MadisonWisconsin-MadisonUnited States
| | - Georgiy Yudintsev
- Neuroscience Program, University of IllinoisUrbana-ChampaignUnited States
| | - Yoshitaka Shinagawa
- Department of Molecular and Integrative Physiology, University of IllinoisUrbana-ChampaignUnited States
| | - Matthew I Banks
- Department of Neuroscience, School of Medicine and Public Health, University of Wisconsin-MadisonWisconsin-MadisonUnited States
- Department of Anesthesiology, School of Medicine and Public Health, University of Wisconsin-MadisonWisconsin-MadisonUnited States
| | - Daniel A Llano
- Department of Molecular and Integrative Physiology, University of IllinoisUrbana-ChampaignUnited States
- Beckman Institute for Advanced Science and Technology, University of IllinoisUrbana-ChampaignUnited States
- Neuroscience Program, University of IllinoisUrbana-ChampaignUnited States
- College of Medicine, University of IllinoisUrbana-ChampaignUnited States
| |
Collapse
|
7
|
O'Reilly C, Iavarone E, Yi J, Hill SL. Rodent somatosensory thalamocortical circuitry: Neurons, synapses, and connectivity. Neurosci Biobehav Rev 2021; 126:213-235. [PMID: 33766672 DOI: 10.1016/j.neubiorev.2021.03.015] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2020] [Revised: 02/15/2021] [Accepted: 03/14/2021] [Indexed: 01/21/2023]
Abstract
As our understanding of the thalamocortical system deepens, the questions we face become more complex. Their investigation requires the adoption of novel experimental approaches complemented with increasingly sophisticated computational modeling. In this review, we take stock of current data and knowledge about the circuitry of the somatosensory thalamocortical loop in rodents, discussing common principles across modalities and species whenever appropriate. We review the different levels of organization, including the cells, synapses, neuroanatomy, and network connectivity. We provide a complete overview of this system that should be accessible for newcomers to this field while nevertheless being comprehensive enough to serve as a reference for seasoned neuroscientists and computational modelers studying the thalamocortical system. We further highlight key gaps in data and knowledge that constitute pressing targets for future experimental work. Filling these gaps would provide invaluable information for systematically unveiling how this system supports behavioral and cognitive processes.
Collapse
Affiliation(s)
- Christian O'Reilly
- Azrieli Centre for Autism Research, Montreal Neurological Institute, McGill University, Montreal, Canada; Ronin Institute, Montclair, NJ, USA; Blue Brain Project, École Polytechnique Fédérale de Lausanne, Geneva, Switzerland.
| | - Elisabetta Iavarone
- Blue Brain Project, École Polytechnique Fédérale de Lausanne, Geneva, Switzerland
| | - Jane Yi
- Brain Mind Institute, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - Sean L Hill
- Blue Brain Project, École Polytechnique Fédérale de Lausanne, Geneva, Switzerland; Department of Psychiatry, University of Toronto, Toronto, Canada; Centre for Addiction and Mental Health, Toronto, Canada.
| |
Collapse
|
8
|
Richardson BD, Sottile SY, Caspary DM. Mechanisms of GABAergic and cholinergic neurotransmission in auditory thalamus: Impact of aging. Hear Res 2020; 402:108003. [PMID: 32703637 DOI: 10.1016/j.heares.2020.108003] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/04/2020] [Revised: 05/15/2020] [Accepted: 05/23/2020] [Indexed: 12/18/2022]
Abstract
Age-related hearing loss is a complex disorder affecting a majority of the elderly population. As people age, speech understanding becomes a challenge especially in complex acoustic settings and negatively impacts the ability to accurately analyze the auditory scene. This is in part due to an inability to focus auditory attention on a particular stimulus source while simultaneously filtering out other sound stimuli. The present review examines the impact of aging on two neurotransmitter systems involved in accurate temporal processing and auditory gating in auditory thalamus (medial geniculate body; MGB), a critical brain region involved in the coding and filtering of auditory information. The inhibitory neurotransmitter GABA and its synaptic receptors (GABAARs) are key to maintaining accurate temporal coding of complex sounds, such as speech, throughout the central auditory system. In the MGB, synaptic and extrasynaptic GABAARs mediate fast phasic and slow tonic inhibition respectively, which in turn regulate MGB neuron excitability, firing modes, and engage thalamocortical oscillations that shape coding and gating of acoustic content. Acoustic coding properties of MGB neurons are further modulated through activation of tegmental cholinergic afferents that project to MGB to potentially modulate attention and help to disambiguate difficult to understand or novel sounds. Acetylcholine is released onto MGB neurons and presynaptic terminals in MGB activating neuronal nicotinic and muscarinic acetylcholine receptors (nAChRs, mAChRs) at a subset of MGB afferents to optimize top-down and bottom-up information flow. Both GABAergic and cholinergic neurotransmission is significantly altered with aging and this review will detail how age-related changes in these circuits within the MGB may impact coding of acoustic stimuli.
Collapse
Affiliation(s)
- B D Richardson
- WWAMI Medical Education, University of Idaho, Moscow, ID, 83844, USA; Biological Engineering, University of Idaho, Moscow, ID, 83844, USA
| | - S Y Sottile
- Center for Clinical Research Southern Illinois University - School of Medicine, Springfield, IL, 62702, USA
| | - D M Caspary
- Department of Pharmacology Southern Illinois University - School of Medicine, Springfield, IL, 62702, USA.
| |
Collapse
|
9
|
Kim H. Stability or Plasticity? - A Hierarchical Allostatic Regulation Model of Medial Prefrontal Cortex Function for Social Valuation. Front Neurosci 2020; 14:281. [PMID: 32296303 PMCID: PMC7138052 DOI: 10.3389/fnins.2020.00281] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2020] [Accepted: 03/12/2020] [Indexed: 12/21/2022] Open
Abstract
The medial prefrontal cortex (mPFC) has long been recognized as the key component of the neurocircuitry involved in various social as well as non-social behaviors, however, little is known regarding the organizing principle of distinctive subregions in the mPFC that integrates a wide range of mPFC functions. The present study proposes a hierarchical model of mPFC functionality, where three functionally dissociable subregions, namely, the ventromedial prefrontal cortex (vmPFC), rostromedial prefrontal cortex (rmPFC), and dorsomedial prefrontal cortex (dmPFC), are differentially involved in computing values of decision-making. According to this model, the mPFC subregions interact with each other in such a way that more dorsal regions utilize additional external sensory information from environment to predict and prevent conflicts occurring in more ventral regions tuned to internal bodily signals, thereby exerting the hierarchically organized allostatic regulatory control over homeostatic reflexes. This model also emphasizes the role of the thalamic reticular nucleus (TRN) in arbitrating the transitions between different thalamo-cortical loops, detecting conflicts between competing options for decision-making, and in shifting flexibly between decision modes. The hierarchical architecture of the mPFC working in conjunction with the TRN may play a key role in adjusting the internal (bodily) needs to suit the constraints of external (environmental) variables better, thus effectively addressing the stability-plasticity dilemma.
Collapse
Affiliation(s)
- Hackjin Kim
- Department of Psychology, Korea University, Seoul, South Korea
| |
Collapse
|
10
|
Brown JW, Taheri A, Kenyon RV, Berger-Wolf TY, Llano DA. Signal Propagation via Open-Loop Intrathalamic Architectures: A Computational Model. eNeuro 2020; 7:ENEURO.0441-19.2020. [PMID: 32005750 PMCID: PMC7053175 DOI: 10.1523/eneuro.0441-19.2020] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2019] [Revised: 01/13/2020] [Accepted: 01/20/2020] [Indexed: 01/06/2023] Open
Abstract
Propagation of signals across the cerebral cortex is a core component of many cognitive processes and is generally thought to be mediated by direct intracortical connectivity. The thalamus, by contrast, is considered to be devoid of internal connections and organized as a collection of parallel inputs to the cortex. Here, we provide evidence that "open-loop" intrathalamic pathways involving the thalamic reticular nucleus (TRN) can support propagation of oscillatory activity across the cortex. Recent studies support the existence of open-loop thalamo-reticulo-thalamic (TC-TRN-TC) synaptic motifs in addition to traditional closed-loop architectures. We hypothesized that open-loop structural modules, when connected in series, might underlie thalamic and, therefore cortical, signal propagation. Using a supercomputing platform to simulate thousands of permutations of a thalamocortical network based on physiological data collected in mice, rats, ferrets, and cats and in which select synapses were allowed to vary both by class and individually, we evaluated the relative capacities of closed-loop and open-loop TC-TRN-TC synaptic configurations to support both propagation and oscillation. We observed that (1) signal propagation was best supported in networks possessing strong open-loop TC-TRN-TC connectivity; (2) intrareticular synapses were neither primary substrates of propagation nor oscillation; and (3) heterogeneous synaptic networks supported more robust propagation of oscillation than their homogeneous counterparts. These findings suggest that open-loop, heterogeneous intrathalamic architectures might complement direct intracortical connectivity to facilitate cortical signal propagation.
Collapse
Affiliation(s)
- Jeffrey W Brown
- College of Medicine, University of Illinois at Urbana-Champaign, Urbana, IL 61801
| | - Aynaz Taheri
- Department of Computer Science, University of Illinois at Chicago, Chicago, IL 60607
| | - Robert V Kenyon
- Department of Computer Science, University of Illinois at Chicago, Chicago, IL 60607
| | - Tanya Y Berger-Wolf
- Department of Computer Science, University of Illinois at Chicago, Chicago, IL 60607
| | - Daniel A Llano
- College of Medicine, University of Illinois at Urbana-Champaign, Urbana, IL 61801
- Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, IL 61801
- Neuroscience Program, University of Illinois at Urbana-Champaign, Urbana, IL 61801
- Department of Molecular and Integrative Physiology, University of Illinois at Urbana-Champaign, Urbana, IL 61801
| |
Collapse
|
11
|
Prefrontal neural dynamics in consciousness. Neuropsychologia 2019; 131:25-41. [DOI: 10.1016/j.neuropsychologia.2019.05.018] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2018] [Revised: 05/17/2019] [Accepted: 05/20/2019] [Indexed: 12/11/2022]
|
12
|
Aizenberg M, Rolón-Martínez S, Pham T, Rao W, Haas JS, Geffen MN. Projection from the Amygdala to the Thalamic Reticular Nucleus Amplifies Cortical Sound Responses. Cell Rep 2019; 28:605-615.e4. [PMID: 31315041 PMCID: PMC7081884 DOI: 10.1016/j.celrep.2019.06.050] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2017] [Revised: 04/29/2019] [Accepted: 06/13/2019] [Indexed: 12/16/2022] Open
Abstract
Many forms of behavior require selective amplification of neuronal representations of relevant environmental signals. Emotional learning enhances sensory responses in the sensory cortex, yet the underlying circuits remain poorly understood. We identify a pathway between the basolateral amygdala (BLA), an emotional learning center in the mouse brain, and the inhibitory reticular nucleus of the thalamus (TRN). Optogenetic activation of BLA suppressed spontaneous, but not tone-evoked, activity in the auditory cortex (AC), amplifying tone-evoked responses. Viral tracing identified BLA projections terminating at TRN. Optogenetic activation of amygdala-TRN projections further amplified tone-evoked responses in the auditory thalamus and cortex. The results are explained by a computational model of the thalamocortical circuitry, in which activation of TRN by BLA primes thalamocortical neurons to relay relevant sensory input. This circuit mechanism shines a neural spotlight on behaviorally relevant signals and provides a potential target for the treatment of neuropsychological disorders.
Collapse
Affiliation(s)
- Mark Aizenberg
- Department of Otorhinolaryngology: HNS, Department of Neuroscience, University of Pennsylvania, Philadelphia, PA, USA
| | - Solymar Rolón-Martínez
- Department of Otorhinolaryngology: HNS, Department of Neuroscience, University of Pennsylvania, Philadelphia, PA, USA
| | - Tuan Pham
- Department of Biological Sciences, Lehigh University, Bethlehem, PA, USA
| | - Winnie Rao
- Department of Otorhinolaryngology: HNS, Department of Neuroscience, University of Pennsylvania, Philadelphia, PA, USA
| | - Julie S Haas
- Department of Biological Sciences, Lehigh University, Bethlehem, PA, USA
| | - Maria N Geffen
- Department of Otorhinolaryngology: HNS, Department of Neuroscience, University of Pennsylvania, Philadelphia, PA, USA.
| |
Collapse
|
13
|
Esmaeeli S, Murphy K, Swords GM, Ibrahim BA, Brown JW, Llano DA. Visual hallucinations, thalamocortical physiology and Lewy body disease: A review. Neurosci Biobehav Rev 2019; 103:337-351. [PMID: 31195000 DOI: 10.1016/j.neubiorev.2019.06.006] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2018] [Revised: 06/03/2019] [Accepted: 06/08/2019] [Indexed: 12/22/2022]
Abstract
One of the core diagnostic criteria for Dementia with Lewy Bodies (DLB) is the presence of visual hallucinations. The presence of hallucinations, along with fluctuations in the level of arousal and sleep disturbance, point to potential pathological mechanisms at the level of the thalamus. However, the potential role of thalamic dysfunction in DLB, particularly as it relates to the presence of formed visual hallucinations is not known. Here, we review the literature on the pathophysiology of DLB with respect to modern theories of thalamocortical function and attempt to derive an understanding of how such hallucinations arise. Based on the available literature, we propose that combined thalamic-thalamic reticular nucleus and thalamocortical pathology may explain the phenomenology of visual hallucinations in DLB. In particular, diminished α7 cholinergic activity in the thalamic reticular nucleus may critically disinhibit thalamocortical activity. Further, concentrated pathological changes within the posterior regions of the thalamus may explain the predilection for the hallucinations to be visual in nature.
Collapse
Affiliation(s)
- Shooka Esmaeeli
- Department of Molecular and Integrative Physiology, University of Illinois at Urbana-Champaign, Urbana, IL, United States
| | - Kathleen Murphy
- Department of Molecular and Integrative Physiology, University of Illinois at Urbana-Champaign, Urbana, IL, United States
| | - Gabriel M Swords
- University of Illinois at Chicago College of Medicine, Chicago, IL, United States
| | - Baher A Ibrahim
- Department of Molecular and Integrative Physiology, University of Illinois at Urbana-Champaign, Urbana, IL, United States; Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, IL, United States
| | - Jeffrey W Brown
- University of Illinois at Chicago College of Medicine, Chicago, IL, United States
| | - Daniel A Llano
- Department of Molecular and Integrative Physiology, University of Illinois at Urbana-Champaign, Urbana, IL, United States; Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, IL, United States; Carle Neuroscience Institute, Urbana, IL, United States.
| |
Collapse
|
14
|
Kimura A, Imbe H. Robust Subthreshold Cross-modal Modulation of Auditory Response by Cutaneous Electrical Stimulation in First- and Higher-order Auditory Thalamic Nuclei. Neuroscience 2018; 372:161-180. [PMID: 29309880 DOI: 10.1016/j.neuroscience.2017.12.051] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2017] [Revised: 12/14/2017] [Accepted: 12/27/2017] [Indexed: 12/14/2022]
Abstract
Conventional extracellular recording has revealed cross-modal alterations of auditory cell activities by cutaneous electrical stimulation of the hindpaw in first- and higher-order auditory thalamic nuclei (Donishi et al., 2011). Juxta-cellular recording and labeling techniques were used in the present study to examine the cross-modal alterations in detail, focusing on possible nucleus and/or cell type-related distinctions in modulation. Recordings were obtained from 80 cells of anesthetized rats. Cutaneous electrical stimulation, which did not elicit unit discharges, i.e., subthreshold effects, modulated early (onset) and/or late auditory responses of first- (64%) and higher-order nucleus cells (77%) with regard to response magnitude, latency and/or burst spiking. Attenuation predominated in the modulation of response magnitude and burst spiking, and delay predominated in the modulation of response time. Striking alterations of burst spiking took place in higher-order nucleus cells, which had the potential to exhibit higher propensities for burst spiking as compared to first-order nucleus cells. A subpopulation of first-order nucleus cells showing modulation in early response magnitude in the caudal domain of the nucleus had larger cell bodies and higher propensities for burst spiking as compared to cells showing no modulation. These findings suggest that somatosensory influence is incorporated into parallel channels in auditory thalamic nuclei to impose distinct impacts on cortical and subcortical sensory processing. Further, cutaneous electrical stimulation given after early auditory responses modulated late responses. Somatosensory influence is likely to affect ongoing auditory processing at any time without being coincident with sound onset in a narrow temporal window.
Collapse
Affiliation(s)
- Akihisa Kimura
- Department of Physiology, Wakayama Medical University, Wakayama Kimiidera 811-1, 641-8509, Japan.
| | - Hiroki Imbe
- Department of Physiology, Wakayama Medical University, Wakayama Kimiidera 811-1, 641-8509, Japan
| |
Collapse
|
15
|
Soto-Sánchez C, Wang X, Vaingankar V, Sommer FT, Hirsch JA. Spatial scale of receptive fields in the visual sector of the cat thalamic reticular nucleus. Nat Commun 2017; 8:800. [PMID: 28986534 PMCID: PMC5630618 DOI: 10.1038/s41467-017-00762-7] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2016] [Accepted: 07/26/2017] [Indexed: 11/12/2022] Open
Abstract
Inhibitory projections from the visual sector of the thalamic reticular nucleus to the lateral geniculate nucleus complete the earliest feedback loop in the mammalian visual pathway and regulate the flow of information from retina to cortex. There are two competing hypotheses about the function of the thalamic reticular nucleus. One regards the structure as a thermostat that uniformly regulates thalamic activity through negative feedback. Alternatively, the searchlight hypothesis argues for a role in focal attentional modulation through positive feedback, consistent with observations that behavioral state influences reticular activity. Here, we address the question of whether cells in the reticular nucleus have receptive fields small enough to provide localized feedback by devising methods to quantify the size of these fields across visual space. Our results show that reticular neurons in the cat operate over discrete spatial scales, at once supporting the searchlight hypothesis and a role in feature selective sensory processing. The searchlight hypothesis proposes that the thalamic reticular nucleus regulates thalamic relay activity through focal attentional modulation. Here the authors show that the receptive field sizes of reticular neurons are small enough to provide localized feedback onto thalamic neurons in the visual pathway.
Collapse
Affiliation(s)
- Cristina Soto-Sánchez
- Department of Biological Sciences and Neuroscience Graduate Program, University of Southern California, 503 HNB, MC 2520, 3641 Watt Way, Los Angeles, CA, 90089-2520, USA.,Biomedical Research Networking Center in Bioengineering, Biomaterials and Nanomedicine (CIBER-BBN), Bioengineering Institute, Miguel Hernández University (UMH), Avda. Universidad s/n, 03202, Elche, Spain
| | - Xin Wang
- Department of Biological Sciences and Neuroscience Graduate Program, University of Southern California, 503 HNB, MC 2520, 3641 Watt Way, Los Angeles, CA, 90089-2520, USA.,Computational Neurobiology Laboratory, The Salk Institute for Biological Studies, 10010 North Torrey Pines Road, La Jolla, CA, 92037, USA
| | - Vishal Vaingankar
- Department of Biological Sciences and Neuroscience Graduate Program, University of Southern California, 503 HNB, MC 2520, 3641 Watt Way, Los Angeles, CA, 90089-2520, USA
| | - Friedrich T Sommer
- Redwood Center for Theoretical Neuroscience-HWNI, University of California at Berkeley, 575A Evans Hall, MC 3198, Berkeley, CA, 94720-3198, USA
| | - Judith A Hirsch
- Department of Biological Sciences and Neuroscience Graduate Program, University of Southern California, 503 HNB, MC 2520, 3641 Watt Way, Los Angeles, CA, 90089-2520, USA.
| |
Collapse
|
16
|
Towards building a more complex view of the lateral geniculate nucleus: Recent advances in understanding its role. Prog Neurobiol 2017. [DOI: 10.1016/j.pneurobio.2017.06.002] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
|
17
|
Kimura A. Robust interactions between the effects of auditory and cutaneous electrical stimulations on cell activities in the thalamic reticular nucleus. Brain Res 2017; 1661:49-66. [DOI: 10.1016/j.brainres.2017.02.005] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2016] [Revised: 02/01/2017] [Accepted: 02/07/2017] [Indexed: 12/27/2022]
|
18
|
Halassa MM, Acsády L. Thalamic Inhibition: Diverse Sources, Diverse Scales. Trends Neurosci 2016; 39:680-693. [PMID: 27589879 DOI: 10.1016/j.tins.2016.08.001] [Citation(s) in RCA: 128] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2016] [Revised: 07/31/2016] [Accepted: 08/02/2016] [Indexed: 12/11/2022]
Abstract
The thalamus is the major source of cortical inputs shaping sensation, action, and cognition. Thalamic circuits are targeted by two major inhibitory systems: the thalamic reticular nucleus (TRN) and extrathalamic inhibitory (ETI) inputs. A unifying framework of how these systems operate is currently lacking. Here, we propose that TRN circuits are specialized to exert thalamic control at different spatiotemporal scales. Local inhibition of thalamic spike rates prevails during attentional selection, whereas global inhibition more likely prevails during sleep. In contrast, the ETI (arising from basal ganglia, zona incerta (ZI), anterior pretectum, and pontine reticular formation) provides temporally precise and focal inhibition, impacting spike timing. Together, these inhibitory systems allow graded control of thalamic output, enabling thalamocortical operations to dynamically match ongoing behavioral demands.
Collapse
Affiliation(s)
- Michael M Halassa
- New York University Neuroscience Institute and the Departments of Psychiatry, Neuroscience and Physiology, New York University Langone Medical Center, New York, 10016, USA; Center for Neural Science, New York University, New York, 10016, USA.
| | - László Acsády
- Laboratory of Thalamus Research, Institute of Experimental Medicine, Hungarian Academy of Sciences, Budapest, 1083 Hungary.
| |
Collapse
|
19
|
Form and Function of Sleep Spindles across the Lifespan. Neural Plast 2016; 2016:6936381. [PMID: 27190654 PMCID: PMC4848449 DOI: 10.1155/2016/6936381] [Citation(s) in RCA: 101] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2016] [Accepted: 03/16/2016] [Indexed: 01/11/2023] Open
Abstract
Since the advent of EEG recordings, sleep spindles have been identified as hallmarks of non-REM sleep. Despite a broad general understanding of mechanisms of spindle generation gleaned from animal studies, the mechanisms underlying certain features of spindles in the human brain, such as “global” versus “local” spindles, are largely unknown. Neither the topography nor the morphology of sleep spindles remains constant throughout the lifespan. It is likely that changes in spindle phenomenology during development and aging are the result of dramatic changes in brain structure and function. Across various developmental windows, spindle activity is correlated with general cognitive aptitude, learning, and memory; however, these correlations vary in strength, and even direction, depending on age and metrics used. Understanding these differences across the lifespan should further clarify how these oscillations are generated and their function under a variety of circumstances. We discuss these issues, and their translational implications for human cognitive function. Because sleep spindles are similarly affected in disorders of neurodevelopment (such as schizophrenia) and during aging (such as neurodegenerative conditions), both types of disorders may benefit from therapies based on a better understanding of spindle function.
Collapse
|
20
|
Willis AM, Slater BJ, Gribkova ED, Llano DA. Open-loop organization of thalamic reticular nucleus and dorsal thalamus: a computational model. J Neurophysiol 2015; 114:2353-67. [PMID: 26289472 PMCID: PMC4620136 DOI: 10.1152/jn.00926.2014] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2014] [Accepted: 08/17/2015] [Indexed: 12/18/2022] Open
Abstract
The thalamic reticular nucleus (TRN) is a shell of GABAergic neurons that surrounds the dorsal thalamus. Previous work has shown that TRN neurons send GABAergic projections to thalamocortical (TC) cells to form reciprocal, closed-loop circuits. This has led to the hypothesis that the TRN is responsible for oscillatory phenomena, such as sleep spindles and absence seizures. However, there is emerging evidence that open-loop circuits are also found between TRN and TC cells. The implications of open-loop configurations are not yet known, particularly when they include time-dependent nonlinearities in TC cells such as low-threshold bursting. We hypothesized that low-threshold bursting in an open-loop circuit could be a mechanism by which the TRN could paradoxically enhance TC activation, and that enhancement would depend on the relative timing of TRN vs. TC cell stimulation. To test this, we modeled small circuits containing TC neurons, TRN neurons, and layer 4 thalamorecipient cells in both open- and closed-loop configurations. We found that open-loop TRN stimulation, rather than universally depressing TC activation, increased cortical output across a broad parameter space, modified the filter properties of TC neurons, and altered the mutual information between input and output in a frequency-dependent and T-type calcium channel-dependent manner. Therefore, an open-loop model of TRN-TC interactions, rather than suppressing transmission through the thalamus, creates a tunable filter whose properties may be modified by outside influences onto the TRN. These simulations make experimentally testable predictions about the potential role for the TRN for flexible enhancement of cortical activation.
Collapse
Affiliation(s)
- Adam M Willis
- Department of Neurology, San Antonio Military Medical Center, Fort Sam Houston, Texas; Department of Theoretical and Applied Mechanics, University of Illinois at Urbana-Champaign, Urbana, Illinois
| | - Bernard J Slater
- Neuroscience Program, University of Illinois at Urbana-Champaign, Urbana, Illinois
| | - Ekaterina D Gribkova
- Department of Molecular and Integrative Physiology, University of Illinois at Urbana-Champaign, Urbana, Illinois; and
| | - Daniel A Llano
- Neuroscience Program, University of Illinois at Urbana-Champaign, Urbana, Illinois; Department of Molecular and Integrative Physiology, University of Illinois at Urbana-Champaign, Urbana, Illinois; and Beckman Institute for Advanced Science and Technology, Urbana, Illinois
| |
Collapse
|
21
|
Kimura A, Imbe H. Anatomically structured burst spiking of thalamic reticular nucleus cells: implications for distinct modulations of sensory processing in lemniscal and non-lemniscal thalamocortical loop circuitries. Eur J Neurosci 2015; 41:1276-93. [DOI: 10.1111/ejn.12874] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2014] [Accepted: 02/11/2015] [Indexed: 11/29/2022]
Affiliation(s)
- Akihisa Kimura
- Department of Physiology; Wakayama Medical University; Wakayama Kimiidera 811-1 641-8509 Wakayama Japan
| | - Hiroki Imbe
- Department of Physiology; Wakayama Medical University; Wakayama Kimiidera 811-1 641-8509 Wakayama Japan
| |
Collapse
|
22
|
Restuccia D, Coppola G. Auditory stimulation enhances thalamic somatosensory high-frequency oscillations in healthy humans: a neurophysiological marker of cross-sensory sensitization? Eur J Neurosci 2015; 41:1079-85. [PMID: 25784489 DOI: 10.1111/ejn.12873] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2014] [Revised: 02/11/2015] [Accepted: 02/12/2015] [Indexed: 12/13/2022]
Abstract
Electrical stimulation of upper limb nerves evokes a train of high-frequency wavelets (high-frequency oscillations, HFOs) on the human scalp. These HFOs are related to the influence of arousal-promoting structures on somatosensory input processing, and are generated in the primary somatosensory cortex (post-synaptic HFOs) and the terminal tracts of thalamocortical radiations (pre-synaptic HFOs). We previously reported that HFOs do not undergo habituation to repeated stimulations; here, we verified whether HFOs could be modulated by external sensitizing stimuli. We recorded somatosensory evoked potentials (SSEPs) in 15 healthy volunteers before and after sensitization training with an auditory stimulus. Pre-synaptic HFO amplitudes, reflecting somatosensory thalamic/thalamocortical activity, significantly increased after the sensitizing acoustic stimulation, whereas both the low-frequency N20 SSEP component and post-synaptic HFOs were unaffected. Cross-talk between subcortical arousal-related structures is a probable mechanism for the pre-synaptic HFO effect observed in this study. We propose that part of the ascending somatosensory input encoded in HFOs is specifically able to convey sensitized inputs. This preferential involvement in sensitization mechanisms suggests that HFOs play a critical role in the detection of potentially relevant stimuli, and act at very early stages of somatosensory input processing.
Collapse
Affiliation(s)
- Domenico Restuccia
- Department of Neurosciences, Catholic University, Largo A. Gemelli 8, Rome, 00168, Italy
| | | |
Collapse
|
23
|
Ahrens S, Jaramillo S, Yu K, Ghosh S, Hwang GR, Paik R, Lai C, He M, Huang ZJ, Li B. ErbB4 regulation of a thalamic reticular nucleus circuit for sensory selection. Nat Neurosci 2014; 18:104-11. [PMID: 25501036 PMCID: PMC4281280 DOI: 10.1038/nn.3897] [Citation(s) in RCA: 82] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2014] [Accepted: 11/14/2014] [Indexed: 02/07/2023]
Abstract
Selective processing of behaviorally relevant sensory inputs against
irrelevant ones is a fundamental cognitive function, impairments of which have
been implicated in major psychiatric disorders. It is known that the thalamic
reticular nucleus (TRN) gates sensory information en route to the cortex,
however the underlying mechanisms remain unclear. Here we show in mice that
deficiency of Erbb4 gene in somatostatin-expressing TRN neurons
markedly altered behaviors dependent on sensory selection. Whereas performance
in identifying targets from distractors was improved, the ability to switch
attention between conflicting sensory cues was impaired. These behavioral
changes were mediated by enhanced cortical drive onto TRN that promotes the
TRN-mediated cortical feedback inhibition of thalamic neurons. Our results
uncover a previously unknown role of ErbB4 in regulating cortico-TRN-thalamic
circuit function. We propose that ErbB4 sets the sensitivity of TRN to cortical
inputs at levels that can support sensory selection while allowing behavioral
flexibility.
Collapse
Affiliation(s)
- Sandra Ahrens
- Cold Spring Harbor Laboratory, Cold Spring Harbor, New York, USA
| | | | - Kai Yu
- Cold Spring Harbor Laboratory, Cold Spring Harbor, New York, USA
| | - Sanchari Ghosh
- Cold Spring Harbor Laboratory, Cold Spring Harbor, New York, USA
| | - Ga-Ram Hwang
- Cold Spring Harbor Laboratory, Cold Spring Harbor, New York, USA
| | - Raehum Paik
- Cold Spring Harbor Laboratory, Cold Spring Harbor, New York, USA
| | - Cary Lai
- Indiana University, Bloomington, Indiana, USA
| | - Miao He
- Cold Spring Harbor Laboratory, Cold Spring Harbor, New York, USA
| | - Z Josh Huang
- Cold Spring Harbor Laboratory, Cold Spring Harbor, New York, USA
| | - Bo Li
- Cold Spring Harbor Laboratory, Cold Spring Harbor, New York, USA
| |
Collapse
|
24
|
Kimura A. Diverse subthreshold cross-modal sensory interactions in the thalamic reticular nucleus: implications for new pathways of cross-modal attentional gating function. Eur J Neurosci 2014; 39:1405-18. [PMID: 24646412 DOI: 10.1111/ejn.12545] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2013] [Revised: 01/26/2014] [Accepted: 02/03/2014] [Indexed: 11/30/2022]
Abstract
Our attention to a sensory cue of a given modality interferes with attention to a sensory cue of another modality. However, an object emitting various sensory cues attracts attention more effectively. The thalamic reticular nucleus (TRN) could play a pivotal role in such cross-modal modulation of attention given that cross-modal sensory interaction takes place in the TRN, because the TRN occupies a highly strategic position to function in the control of gain and/or gating of sensory processing in the thalamocortical loop. In the present study cross-modal interactions between visual and auditory inputs were examined in single TRN cells of anesthetised rats using juxta-cellular recording and labeling techniques. Visual or auditory responses were modulated by subthreshold sound or light stimuli, respectively, in the majority of recordings (46 of 54 visual and 60 of 73 auditory cells). However, few bimodal sensory cells were found. Cells showing modulation of the sensory response were distributed in the whole visual and auditory sectors of the TRN. Modulated cells sent axonal projections to first-order or higher-order thalamic nuclei. Suppression predominated in modulation that took place not only in primary responses but also in late responses repeatedly evoked after sensory stimulation. Combined sensory stimulation also evoked de-novo responses, and modulated response latency and burst spiking. These results indicate that the TRN incorporates sensory inputs of different modalities into single cell activity to function in sensory processing in the lemniscal and non-lemniscal systems. This raises the possibility that the TRN constitutes neural pathways involved in cross-modal attentional gating.
Collapse
Affiliation(s)
- Akihisa Kimura
- Department of Physiology, Wakayama Medical University, Wakayama Kimiidera 811-1, Wakayama, 641-8509, Japan
| |
Collapse
|
25
|
Bartlett EL. The organization and physiology of the auditory thalamus and its role in processing acoustic features important for speech perception. BRAIN AND LANGUAGE 2013; 126:29-48. [PMID: 23725661 PMCID: PMC3707394 DOI: 10.1016/j.bandl.2013.03.003] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/24/2012] [Revised: 02/28/2013] [Accepted: 03/19/2013] [Indexed: 05/17/2023]
Abstract
The auditory thalamus, or medial geniculate body (MGB), is the primary sensory input to auditory cortex. Therefore, it plays a critical role in the complex auditory processing necessary for robust speech perception. This review will describe the functional organization of the thalamus as it relates to processing acoustic features important for speech perception, focusing on thalamic nuclei that relate to auditory representations of language sounds. The MGB can be divided into three main subdivisions, the ventral, dorsal, and medial subdivisions, each with different connectivity, auditory response properties, neuronal properties, and synaptic properties. Together, the MGB subdivisions actively and dynamically shape complex auditory processing and form ongoing communication loops with auditory cortex and subcortical structures.
Collapse
|
26
|
León-Domínguez U, Vela-Bueno A, Froufé-Torres M, León-Carrión J. A chronometric functional sub-network in the thalamo-cortical system regulates the flow of neural information necessary for conscious cognitive processes. Neuropsychologia 2013; 51:1336-49. [DOI: 10.1016/j.neuropsychologia.2013.03.012] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2012] [Revised: 03/13/2013] [Accepted: 03/21/2013] [Indexed: 01/28/2023]
|
27
|
Abstract
Age-related deficits in detecting and understanding speech, which can lead to social withdrawal and isolation, have been linked to changes in the central auditory system. Many of these central age-related changes involve altered mechanisms of inhibitory neurotransmission, essential for accurate and reliable auditory processing. In sensory thalamus, GABA mediates fast (phasic) inhibition via synaptic GABA(A) receptors (GABA(A)Rs) and long-lasting (tonic) inhibition via high-affinity (extrasynaptic) GABA(A)Rs, which provide a majority of the overall inhibitory tone in sensory thalamus. Due to a delicate balance between excitation and inhibition, alteration of normal thalamic inhibitory function with age and a reduction of tonic GABA(A)R-mediated inhibition may disrupt normal adult auditory processing, sensory gating, thalamocortical rhythmicity, and slow-wave sleep. The present study examines age-related homeostatic plasticity of GABA(A)R function in auditory thalamus or the medial geniculate body (MGB). Using thalamic slices from young adult (3-8 months) and aged (28-32 months) rats, these studies found a 45.5% reduction in GABA(A)R density and a 50.4% reduction in GABA(A)R-mediated tonic whole cell Cl(-) currents in the aged MGB. Synaptic GABA(A)R-mediated inhibition appeared differentially affected in aged lemniscal and nonlemniscal MGB. Except for resting membrane potential, basic properties were unaltered with age, including neuronal Cl(-) homeostasis determined using the gramicidin perforated patch-clamp method. Results demonstrate selective significant age-dependent deficits in the tonic inhibitory tone within the MGB. These data suggest that selective GABA(A)R subtype agonists or modulators might be used to augment MGB inhibitory neurotransmission, improving speech understanding, sensory gating, and slow-wave sleep for a subset of elderly individuals.
Collapse
|
28
|
Vaingankar V, Soto-Sanchez C, Wang X, Sommer FT, Hirsch JA. Neurons in the thalamic reticular nucleus are selective for diverse and complex visual features. Front Integr Neurosci 2012; 6:118. [PMID: 23269915 PMCID: PMC3529363 DOI: 10.3389/fnint.2012.00118] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2012] [Accepted: 11/29/2012] [Indexed: 11/13/2022] Open
Abstract
All visual signals the cortex receives are influenced by the perigeniculate sector (PGN) of the thalamic reticular nucleus, which receives input from relay cells in the lateral geniculate and provides feedback inhibition in return. Relay cells have been studied in quantitative depth; they behave in a roughly linear fashion and have receptive fields with a stereotyped center-surround structure. We know far less about reticular neurons. Qualitative studies indicate they simply pool ascending input to generate non-selective gain control. Yet the perigeniculate is complicated; local cells are densely interconnected and fire lengthy bursts. Thus, we employed quantitative methods to explore the perigeniculate using relay cells as controls. By adapting methods of spike-triggered averaging and covariance analysis for bursts, we identified both first and second order features that build reticular receptive fields. The shapes of these spatiotemporal subunits varied widely; no stereotyped pattern emerged. Companion experiments showed that the shape of the first but not second order features could be explained by the overlap of On and Off inputs to a given cell. Moreover, we assessed the predictive power of the receptive field and how much information each component subunit conveyed. Linear-non-linear (LN) models including multiple subunits performed better than those made with just one; further each subunit encoded different visual information. Model performance for reticular cells was always lesser than for relay cells, however, indicating that reticular cells process inputs non-linearly. All told, our results suggest that the perigeniculate encodes diverse visual features to selectively modulate activity transmitted downstream.
Collapse
Affiliation(s)
- Vishal Vaingankar
- Department of Biological Sciences and Neuroscience Graduate Program, University of Southern CaliforniaLos Angeles, CA, USA
| | - Cristina Soto-Sanchez
- Department of Biological Sciences and Neuroscience Graduate Program, University of Southern CaliforniaLos Angeles, CA, USA
| | - Xin Wang
- Computational Neurobiology Laboratory, The Salk Institute for Biological StudiesLa Jolla, CA, USA
| | - Friedrich T. Sommer
- Redwood Center for Theoretical Neuroscience, University of CaliforniaBerkeley, CA, USA
| | - Judith A. Hirsch
- Department of Biological Sciences and Neuroscience Graduate Program, University of Southern CaliforniaLos Angeles, CA, USA
| |
Collapse
|
29
|
Kimura A, Yokoi I, Imbe H, Donishi T, Kaneoke Y. Auditory thalamic reticular nucleus of the rat: Anatomical nodes for modulation of auditory and cross-modal sensory processing in the loop connectivity between the cortex and thalamus. J Comp Neurol 2012; 520:1457-80. [DOI: 10.1002/cne.22805] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
|
30
|
Yu XJ, Meng XK, Xu XX, He J. Individual auditory thalamic reticular neurons have large and cross-modal sources of cortical and thalamic inputs. Neuroscience 2011; 193:122-31. [DOI: 10.1016/j.neuroscience.2011.07.040] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2011] [Revised: 07/19/2011] [Accepted: 07/20/2011] [Indexed: 10/17/2022]
|
31
|
Jääskeläinen IP, Ahveninen J, Andermann ML, Belliveau JW, Raij T, Sams M. Short-term plasticity as a neural mechanism supporting memory and attentional functions. Brain Res 2011; 1422:66-81. [PMID: 21985958 DOI: 10.1016/j.brainres.2011.09.031] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2011] [Revised: 08/16/2011] [Accepted: 09/16/2011] [Indexed: 10/17/2022]
Abstract
Based on behavioral studies, several relatively distinct perceptual and cognitive functions have been defined in cognitive psychology such as sensory memory, short-term memory, and selective attention. Here, we review evidence suggesting that some of these functions may be supported by shared underlying neuronal mechanisms. Specifically, we present, based on an integrative review of the literature, a hypothetical model wherein short-term plasticity, in the form of transient center-excitatory and surround-inhibitory modulations, constitutes a generic processing principle that supports sensory memory, short-term memory, involuntary attention, selective attention, and perceptual learning. In our model, the size and complexity of receptive fields/level of abstraction of neural representations, as well as the length of temporal receptive windows, increases as one steps up the cortical hierarchy. Consequently, the type of input (bottom-up vs. top down) and the level of cortical hierarchy that the inputs target, determine whether short-term plasticity supports purely sensory vs. semantic short-term memory or attentional functions. Furthermore, we suggest that rather than discrete memory systems, there are continuums of memory representations from short-lived sensory ones to more abstract longer-duration representations, such as those tapped by behavioral studies of short-term memory.
Collapse
Affiliation(s)
- Iiro P Jääskeläinen
- Brain and Mind Laboratory, Department of Biomedical Engineering and Computational Science, Aalto University, School of Science, Espoo, Finland.
| | | | | | | | | | | |
Collapse
|
32
|
Stimulus-specific adaptation in the gerbil primary auditory thalamus is the result of a fast frequency-specific habituation and is regulated by the corticofugal system. J Neurosci 2011; 31:9708-22. [PMID: 21715636 DOI: 10.1523/jneurosci.5814-10.2011] [Citation(s) in RCA: 80] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The detection of novel and therefore potentially behavioral relevant stimuli is of fundamental importance for animals. In the auditory system, stimulus-specific adaptation (SSA) resulting in stronger responses to rare compared with frequent stimuli was proposed as such a novelty detection mechanism. SSA is a now well established phenomenon found at different levels along the mammalian auditory pathway. It depends on various stimulus features, such as deviant probability, and may be an essential mechanism underlying perception of changes in sound statistics. We recorded neuronal responses from the ventral part of the medial geniculate body (vMGB) in Mongolian gerbils to determine details of the adaptation process that might indicate underlying neuronal mechanisms. Neurons in the vMGB exhibited a median spike rate change of 15.4% attributable to a fast habituation to the frequently presented standard stimulus. Accordingly, the main habituation effect could also be induced by the repetition of a few uniform tonal stimuli. The degree of habituation was frequency-specific, and comparison across simultaneously recorded units indicated that adaptation effects were apparently topographically organized. At the population level, stronger habituation effects were on average associated with the border regions of the frequency response areas. Finally, the pharmacological inactivation of the auditory cortex demonstrated that SSA in the vMGB is mainly regulated by the corticofugal system. Hence, these results indicate a more general function of SSA in the processing and analysis of auditory information than the term novelty detection suggests.
Collapse
|
33
|
Abstract
AbstractThe cingulate cortex (CG) and the adjacent region designated as the splenial visual area (SVA) project to areas of the extrageniculate thalamic system that are concerned with processing visual information. En route to the thalamus, they pass through the thalamic reticular nucleus (TRN), an important source of thalamic inhibition. We wished to determine whether SVA axon collaterals projected to the previously defined visual sector of the TRN or a separate projection zone and did this differ from the projection zone of CG. We iontophoretically injected different neuroanatomical tracers into several locations within CG/SVA and traced the labeled axons through the TRN. The CG and SVA have a projection zone that only partially overlaps the dorsorostral regions of the visuocortical projection zone; there was no evidence to suggest separate SVA and CG zones or tiers of label within the TRN. The projection formed only a weak topographic map in the TRN, which is largely defined in the rostrocaudal axis and is similar to that of the area 7 projection; both projections have a high degree of overlap in the dorsal TRN. We postulate that CG/SVA may be involved in the initiation of orientation behaviors via stimulation of thalamic nuclei and attentional mechanisms of the TRN.
Collapse
|
34
|
Sub-threshold cross-modal sensory interaction in the thalamus: lemniscal auditory response in the medial geniculate nucleus is modulated by somatosensory stimulation. Neuroscience 2011; 174:200-15. [DOI: 10.1016/j.neuroscience.2010.11.041] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2010] [Revised: 11/19/2010] [Accepted: 11/19/2010] [Indexed: 11/19/2022]
|
35
|
Auditory cortex spatial sensitivity sharpens during task performance. Nat Neurosci 2010; 14:108-14. [PMID: 21151120 PMCID: PMC3076022 DOI: 10.1038/nn.2713] [Citation(s) in RCA: 142] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2010] [Accepted: 11/13/2010] [Indexed: 11/13/2022]
Abstract
Activity in the primary auditory cortex (A1) is known to be essential for normal sound localization behavior, yet previous studies of the spatial sensitivity of neurons in A1 have found surprisingly broad spatial tuning. We tested the hypothesis that spatial tuning sharpens when an animal engages in an auditory task. Cats performed a task that required evaluation of the locations of sounds and another that required active listening but in which sound location was irrelevant. Some 26–44% of the units recorded in A1 showed significantly sharpened spatial tuning during the behavioral tasks compared to idle conditions, with greatest sharpening during the location-relevant task. Spatial sharpening occurred on a scale of tens of seconds and could be replicated multiple times within ~1.5-hr test sessions. Sharpening resulted primarily from increased suppression of responses to sounds at least-preferred locations. That and an observed increase in latencies suggest an important role of inhibitory mechanisms.
Collapse
|
36
|
Kimura A, Imbe H, Donishi T. Efferent connections of an auditory area in the caudal insular cortex of the rat: anatomical nodes for cortical streams of auditory processing and cross-modal sensory interactions. Neuroscience 2010; 166:1140-57. [DOI: 10.1016/j.neuroscience.2010.01.032] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2009] [Revised: 01/15/2010] [Accepted: 01/15/2010] [Indexed: 11/30/2022]
|
37
|
Kimura A, Imbe H, Donishi T. Axonal projections of auditory cells with short and long response latencies in the medial geniculate nucleus: distinct topographies in the connection with the thalamic reticular nucleus. Eur J Neurosci 2009; 30:783-99. [PMID: 19712090 DOI: 10.1111/j.1460-9568.2009.06880.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The thalamic reticular nucleus (TRN) is a crucial anatomical node of thalamocortical connectivity for sensory processing. In the rat auditory system, we determined features of thalamic projections to the TRN, using juxtacellular recording and labeling techniques. Two types of auditory cells (short latency, SL, and long latency, LL), exhibiting unit discharges to noise burst stimuli (duration, 100 ms) with short (< 50 ms) and long (> 100 ms) response latencies, were obtained from the ventral division of the medial geniculate nucleus (MGV). Both SL and LL cells had a propensity to exhibit reverberatory discharges in response to sound stimuli. The primary discharges of SL cells were mostly single spikes while the non-primary discharges of SL cells and the whole discharges of LL cells were mostly burst spikes. SL cells sent topographic projections to the TRN along the dorsoventral and rostrocaudal neural axes while LL cells only along the rostrocaudal axis. As tonotopy-related cortical projections to the TRN are topographic primarily along the dorsoventral extent of the TRN and the MGV is tonotopically organized along the dorsoventral axis, SL cells, directly activated by ascending auditory inputs, may be closely involved in tonotopic thalamocortical connectivity. On the other hand, LL cells, which are suppressed by ascending inputs and could be driven to discharge by corticofugal inputs, are assumed to activate the TRN in a manner less related to tonotopic organization. There may exist heterogeneous projections from the MGV to the TRN, which, in conjunction with corticofugal connections, could constitute distinct channels of auditory processing.
Collapse
Affiliation(s)
- Akihisa Kimura
- Department of Physiology, Wakayama Medical University, Kimiidera 811-1, Wakayama, Japan.
| | | | | |
Collapse
|
38
|
Llano DA, Theyel BB, Mallik AK, Sherman SM, Issa NP. Rapid and sensitive mapping of long-range connections in vitro using flavoprotein autofluorescence imaging combined with laser photostimulation. J Neurophysiol 2009; 101:3325-40. [PMID: 19321634 DOI: 10.1152/jn.91291.2008] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
We investigated the use of flavoprotein autofluorescence (FA) as a tool to map long-range neural connections and combined FA with laser-uncaging of glutamate to facilitate rapid long-range mapping in vitro. Using the somatosensory thalamocortical slice, we determined that the spatial resolution of FA is >or=100-200 microm and that the sensitivity for detecting thalamocortical synaptic activity approximates that of whole cell recording. Blockade of ionotropic glutamate receptors with DNQX and AP5 abolished cortical responses to electrical thalamic stimulation. The combination of FA with photostimulation using caged glutamate revealed robust long-distance connectivity patterns that could be readily assessed in slices from the somatosensory, auditory, and visual systems that contained thalamocortical, corticothalamic, or corticocortical connections. We mapped the projection from the ventral posterior nucleus of thalamus (VPM) to the primary somatosensory cortex-barrel field and confirmed topography that had been previously described using more laborious methods. We also produced a novel map of the projections from the VPM to the thalamic reticular nucleus, showing precise topography along the dorsoventral axis. Importantly, only about 30 s were needed to generate the connectivity map (six stimulus locations). These data suggest that FA is a sensitive tool for exploring and measuring connectivity and, when coupled with glutamate photostimulation, can rapidly map long-range projections in a single animal.
Collapse
Affiliation(s)
- D A Llano
- Department of Neurology, University of Chicago, Chicago, Illinois 60637, USA.
| | | | | | | | | |
Collapse
|
39
|
Current World Literature. Curr Opin Otolaryngol Head Neck Surg 2008; 16:490-5. [DOI: 10.1097/moo.0b013e3283130f63] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
|