1
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Londoño‐Ramírez H, Huang X, Cools J, Chrzanowska A, Brunner C, Ballini M, Hoffman L, Steudel S, Rolin C, Mora Lopez C, Genoe J, Haesler S. Multiplexed Surface Electrode Arrays Based on Metal Oxide Thin-Film Electronics for High-Resolution Cortical Mapping. Adv Sci (Weinh) 2024; 11:e2308507. [PMID: 38145348 PMCID: PMC10933637 DOI: 10.1002/advs.202308507] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/08/2023] [Revised: 12/15/2023] [Indexed: 12/26/2023]
Abstract
Electrode grids are used in neuroscience research and clinical practice to record electrical activity from the surface of the brain. However, existing passive electrocorticography (ECoG) technologies are unable to offer both high spatial resolution and wide cortical coverage, while ensuring a compact acquisition system. The electrode count and density are restricted by the fact that each electrode must be individually wired. This work presents an active micro-electrocorticography (µECoG) implant that tackles this limitation by incorporating metal oxide thin-film transistors (TFTs) into a flexible electrode array, allowing to address multiple electrodes through a single shared readout line. By combining the array with an incremental-ΔΣ readout integrated circuit (ROIC), the system is capable of recording from up to 256 electrodes virtually simultaneously, thanks to the implemented 16:1 time-division multiplexing scheme, offering lower noise levels than existing active µECoG arrays. In vivo validation is demonstrated acutely in mice by recording spontaneous activity and somatosensory evoked potentials over a cortical surface of ≈8×8 mm2 . The proposed neural interface overcomes the wiring bottleneck limiting ECoG arrays, holding promise as a powerful tool for improved mapping of the cerebral cortex and as an enabling technology for future brain-machine interfaces.
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Affiliation(s)
- Horacio Londoño‐Ramírez
- Department of Neuroscience, Leuven Brain InstituteKatholieke Universiteit (KU) LeuvenLeuven3001Belgium
- Neuroelectronics Research Flanders (NERF)Leuven3001Belgium
- imecLeuven3001Belgium
- Flanders Institute for Biotechnology (VIB)Gent9052Belgium
| | - Xiaohua Huang
- imecLeuven3001Belgium
- Department of Electrical Engineering (ESAT)Katholieke Universiteit (KU) LeuvenLeuven3001Belgium
| | - Jordi Cools
- Neuroelectronics Research Flanders (NERF)Leuven3001Belgium
- imecLeuven3001Belgium
- Flanders Institute for Biotechnology (VIB)Gent9052Belgium
- Present address:
Thermo Fisher Scientific3001LeuvenBelgium
| | - Anna Chrzanowska
- Neuroelectronics Research Flanders (NERF)Leuven3001Belgium
- Flanders Institute for Biotechnology (VIB)Gent9052Belgium
- Department of BiologyKatholieke Universiteit (KU) LeuvenLeuven3001Belgium
| | - Clément Brunner
- Department of Neuroscience, Leuven Brain InstituteKatholieke Universiteit (KU) LeuvenLeuven3001Belgium
- Neuroelectronics Research Flanders (NERF)Leuven3001Belgium
- Flanders Institute for Biotechnology (VIB)Gent9052Belgium
| | - Marco Ballini
- imecLeuven3001Belgium
- Present address:
Microphone Business Unit, TDK InvenSense20057MilanItaly
| | - Luis Hoffman
- Neuroelectronics Research Flanders (NERF)Leuven3001Belgium
- imecLeuven3001Belgium
- Present address:
Swave Photonics3001LeuvenBelgium
| | - Soeren Steudel
- imecLeuven3001Belgium
- Present address:
MICLEDI Microdisplays3001LeuvenBelgium
| | | | | | - Jan Genoe
- Department of Electrical Engineering (ESAT)Katholieke Universiteit (KU) LeuvenLeuven3001Belgium
| | - Sebastian Haesler
- Department of Neuroscience, Leuven Brain InstituteKatholieke Universiteit (KU) LeuvenLeuven3001Belgium
- Neuroelectronics Research Flanders (NERF)Leuven3001Belgium
- Flanders Institute for Biotechnology (VIB)Gent9052Belgium
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2
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Modirshanechi A, Kondrakiewicz K, Gerstner W, Haesler S. Curiosity-driven exploration: foundations in neuroscience and computational modeling. Trends Neurosci 2023; 46:1054-1066. [PMID: 37925342 DOI: 10.1016/j.tins.2023.10.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2023] [Revised: 09/28/2023] [Accepted: 10/04/2023] [Indexed: 11/06/2023]
Abstract
Curiosity refers to the intrinsic desire of humans and animals to explore the unknown, even when there is no apparent reason to do so. Thus far, no single, widely accepted definition or framework for curiosity has emerged, but there is growing consensus that curious behavior is not goal-directed but related to seeking or reacting to information. In this review, we take a phenomenological approach and group behavioral and neurophysiological studies which meet these criteria into three categories according to the type of information seeking observed. We then review recent computational models of curiosity from the field of machine learning and discuss how they enable integrating different types of information seeking into one theoretical framework. Combinations of behavioral and neurophysiological studies along with computational modeling will be instrumental in demystifying the notion of curiosity.
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Affiliation(s)
| | - Kacper Kondrakiewicz
- Neuroelectronics Research Flanders (NERF), Leuven, Belgium; VIB, Leuven, Belgium; Department of Neuroscience, KU Leuven, Leuven, Belgium
| | - Wulfram Gerstner
- École Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland.
| | - Sebastian Haesler
- Neuroelectronics Research Flanders (NERF), Leuven, Belgium; VIB, Leuven, Belgium; Department of Neuroscience, KU Leuven, Leuven, Belgium; Leuven Brain Institute, Leuven, Belgium.
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3
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Libbrecht S, Van den Haute C, Welkenhuysen M, Braeken D, Haesler S, Baekelandt V. Chronic chemogenetic stimulation of the anterior olfactory nucleus reduces newborn neuron survival in the adult mouse olfactory bulb. J Neurochem 2021; 158:1186-1198. [PMID: 34338310 DOI: 10.1111/jnc.15486] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2020] [Revised: 07/29/2021] [Accepted: 07/30/2021] [Indexed: 01/06/2023]
Abstract
During adult rodent life, newborn neurons are added to the olfactory bulb (OB) in a tightly controlled manner. Upon arrival in the OB, input synapses from the local bulbar network and the higher olfactory cortex precede the formation of functional output synapses, indicating a possible role for these regions in newborn neuron survival. An interplay between the environment and the piriform cortex in the regulation of newborn neuron survival has been suggested. However, the specific network and the neuronal cell types responsible for this effect have not been elucidated. Furthermore, the role of the other olfactory cortical areas in this process is not known. Here we demonstrate that pyramidal neurons in the mouse anterior olfactory nucleus, the first cortical area for odor processing, have a key role in the survival of newborn neurons. Using DREADD (Designer Receptors Exclusively Activated by Designer Drugs) technology, we applied chronic stimulation to the anterior olfactory nucleus and observed a decrease in newborn neurons in the OB through induction of apoptosis. These findings provide further insight into the network regulating neuronal survival in adult neurogenesis and strengthen the importance of the surrounding network for sustained integration of new neurons.
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Affiliation(s)
- Sarah Libbrecht
- Laboratory for Neurobiology and Gene Therapy, Department of Neurosciences, Leuven Brain Institute, KU Leuven, Leuven, Belgium.,Life Science Technologies Department, Imec, Leuven, Belgium
| | - Chris Van den Haute
- Laboratory for Neurobiology and Gene Therapy, Department of Neurosciences, Leuven Brain Institute, KU Leuven, Leuven, Belgium.,Leuven Viral Vector Core, KU Leuven, Leuven, Belgium
| | | | - Dries Braeken
- Life Science Technologies Department, Imec, Leuven, Belgium
| | - Sebastian Haesler
- Research Group Neurophysiology, Department of Neurosciences, KU Leuven, Leuven, Belgium.,VIB, Leuven, Belgium.,Neuroelectronics Research Flanders, Leuven, Belgium
| | - Veerle Baekelandt
- Laboratory for Neurobiology and Gene Therapy, Department of Neurosciences, Leuven Brain Institute, KU Leuven, Leuven, Belgium
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4
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van Daal RJJ, Aydin Ç, Michon F, Aarts AAA, Kraft M, Kloosterman F, Haesler S. Implantation of Neuropixels probes for chronic recording of neuronal activity in freely behaving mice and rats. Nat Protoc 2021; 16:3322-3347. [PMID: 34108732 DOI: 10.1038/s41596-021-00539-9] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2020] [Accepted: 03/22/2021] [Indexed: 11/09/2022]
Abstract
How dynamic activity in neural circuits gives rise to behavior is a major area of interest in neuroscience. A key experimental approach for addressing this question involves measuring extracellular neuronal activity in awake, behaving animals. Recently developed Neuropixels probes have provided a step change in recording neural activity in large tissue volumes with high spatiotemporal resolution. This protocol describes the chronic implantation of Neuropixels probes in mice and rats using compact and reusable 3D-printed fixtures. The fixtures facilitate stable chronic in vivo recordings in freely behaving rats and mice. They consist of two parts: a covered main body and a skull connector. Single-, dual- and movable-probe fixture variants are available. After completing an experiment, probes are safely recovered for reimplantation by a dedicated retrieval mechanism. Fixture assembly and surgical implantation typically take 4-5 h, and probe retrieval takes ~30 min, followed by 12 h of incubation in probe cleaning agent. The duration of data acquisition depends on the type of behavioral experiment. Since our protocol enables stable, chronic recordings over weeks, it enables longitudinal large-scale single-unit data to be routinely obtained in a cost-efficient manner, which will facilitate many studies in systems neuroscience.
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Affiliation(s)
- Rik J J van Daal
- Neuroelectronics Research Flanders, Leuven, Belgium
- ATLAS Neuroengineering, Leuven, Belgium
- Department of Electrical Engineering, KU Leuven, Leuven, Belgium
| | - Çağatay Aydin
- Neuroelectronics Research Flanders, Leuven, Belgium
- Department of Neurosciences, KU Leuven, Leuven, Belgium
| | - Frédéric Michon
- Neuroelectronics Research Flanders, Leuven, Belgium
- VIB, Leuven, Belgium
| | | | - Michael Kraft
- Department of Electrical Engineering, KU Leuven, Leuven, Belgium
| | - Fabian Kloosterman
- Neuroelectronics Research Flanders, Leuven, Belgium.
- VIB, Leuven, Belgium.
- Brain and Cognition, KU Leuven, Leuven, Belgium.
- Imec, Leuven, Belgium.
| | - Sebastian Haesler
- Neuroelectronics Research Flanders, Leuven, Belgium.
- Department of Neurosciences, KU Leuven, Leuven, Belgium.
- VIB, Leuven, Belgium.
- Imec, Leuven, Belgium.
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5
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Steinmetz NA, Aydin C, Lebedeva A, Okun M, Pachitariu M, Bauza M, Beau M, Bhagat J, Böhm C, Broux M, Chen S, Colonell J, Gardner RJ, Karsh B, Kloosterman F, Kostadinov D, Mora-Lopez C, O'Callaghan J, Park J, Putzeys J, Sauerbrei B, van Daal RJJ, Vollan AZ, Wang S, Welkenhuysen M, Ye Z, Dudman JT, Dutta B, Hantman AW, Harris KD, Lee AK, Moser EI, O'Keefe J, Renart A, Svoboda K, Häusser M, Haesler S, Carandini M, Harris TD. Neuropixels 2.0: A miniaturized high-density probe for stable, long-term brain recordings. Science 2021. [PMID: 33859006 DOI: 10.1101/2020.10.27.358291] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
Measuring the dynamics of neural processing across time scales requires following the spiking of thousands of individual neurons over milliseconds and months. To address this need, we introduce the Neuropixels 2.0 probe together with newly designed analysis algorithms. The probe has more than 5000 sites and is miniaturized to facilitate chronic implants in small mammals and recording during unrestrained behavior. High-quality recordings over long time scales were reliably obtained in mice and rats in six laboratories. Improved site density and arrangement combined with newly created data processing methods enable automatic post hoc correction for brain movements, allowing recording from the same neurons for more than 2 months. These probes and algorithms enable stable recordings from thousands of sites during free behavior, even in small animals such as mice.
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Affiliation(s)
- Nicholas A Steinmetz
- UCL Institute of Ophthalmology, University College London, London, UK.
- Department of Biological Structure, University of Washington, Seattle, WA, USA
| | | | - Anna Lebedeva
- Sainsbury Wellcome Centre, University College London, London, UK
| | - Michael Okun
- Centre for Systems Neuroscience and Department of Neuroscience, Psychology and Behaviour, University of Leicester, Leicester, UK
- UCL Queen Square Institute of Neurology, University College London, London, UK
| | - Marius Pachitariu
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA, USA
| | - Marius Bauza
- Sainsbury Wellcome Centre, University College London, London, UK
| | - Maxime Beau
- Wolfson Institute for Biomedical Research, University College London, London, UK
| | - Jai Bhagat
- UCL Queen Square Institute of Neurology, University College London, London, UK
| | - Claudia Böhm
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA, USA
| | | | - Susu Chen
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA, USA
| | - Jennifer Colonell
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA, USA
| | - Richard J Gardner
- Kavli Institute for Systems Neuroscience, Norwegian University of Science and Technology, Trondheim, Norway
| | - Bill Karsh
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA, USA
| | - Fabian Kloosterman
- Neuroelectronics Research Flanders, Leuven, Belgium
- IMEC, Leuven, Belgium
- Vlaams Instituut voor Biotechnologie (VIB), Leuven, Belgium
- Brain and Cognition, KU Leuven, Leuven, Belgium
| | - Dimitar Kostadinov
- Wolfson Institute for Biomedical Research, University College London, London, UK
| | | | | | - Junchol Park
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA, USA
| | | | - Britton Sauerbrei
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA, USA
| | - Rik J J van Daal
- ATLAS Neuroengineering, Leuven, Belgium
- Neuroelectronics Research Flanders, Leuven, Belgium
- Micro- and Nanosystems, KU Leuven, Leuven, Belgium
| | - Abraham Z Vollan
- Kavli Institute for Systems Neuroscience, Norwegian University of Science and Technology, Trondheim, Norway
| | | | | | - Zhiwen Ye
- Department of Biological Structure, University of Washington, Seattle, WA, USA
| | - Joshua T Dudman
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA, USA
| | | | - Adam W Hantman
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA, USA
| | - Kenneth D Harris
- UCL Queen Square Institute of Neurology, University College London, London, UK
| | - Albert K Lee
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA, USA
| | - Edvard I Moser
- Kavli Institute for Systems Neuroscience, Norwegian University of Science and Technology, Trondheim, Norway
| | - John O'Keefe
- Sainsbury Wellcome Centre, University College London, London, UK
| | | | - Karel Svoboda
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA, USA
| | - Michael Häusser
- Wolfson Institute for Biomedical Research, University College London, London, UK
| | - Sebastian Haesler
- Neuroelectronics Research Flanders, Leuven, Belgium
- Vlaams Instituut voor Biotechnologie (VIB), Leuven, Belgium
| | - Matteo Carandini
- UCL Institute of Ophthalmology, University College London, London, UK.
| | - Timothy D Harris
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA, USA.
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6
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Steinmetz NA, Aydin C, Lebedeva A, Okun M, Pachitariu M, Bauza M, Beau M, Bhagat J, Böhm C, Broux M, Chen S, Colonell J, Gardner RJ, Karsh B, Kloosterman F, Kostadinov D, Mora-Lopez C, O'Callaghan J, Park J, Putzeys J, Sauerbrei B, van Daal RJJ, Vollan AZ, Wang S, Welkenhuysen M, Ye Z, Dudman JT, Dutta B, Hantman AW, Harris KD, Lee AK, Moser EI, O'Keefe J, Renart A, Svoboda K, Häusser M, Haesler S, Carandini M, Harris TD. Neuropixels 2.0: A miniaturized high-density probe for stable, long-term brain recordings. Science 2021; 372:eabf4588. [PMID: 33859006 PMCID: PMC8244810 DOI: 10.1126/science.abf4588] [Citation(s) in RCA: 307] [Impact Index Per Article: 102.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2020] [Accepted: 03/01/2021] [Indexed: 12/22/2022]
Abstract
Measuring the dynamics of neural processing across time scales requires following the spiking of thousands of individual neurons over milliseconds and months. To address this need, we introduce the Neuropixels 2.0 probe together with newly designed analysis algorithms. The probe has more than 5000 sites and is miniaturized to facilitate chronic implants in small mammals and recording during unrestrained behavior. High-quality recordings over long time scales were reliably obtained in mice and rats in six laboratories. Improved site density and arrangement combined with newly created data processing methods enable automatic post hoc correction for brain movements, allowing recording from the same neurons for more than 2 months. These probes and algorithms enable stable recordings from thousands of sites during free behavior, even in small animals such as mice.
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Affiliation(s)
- Nicholas A Steinmetz
- UCL Institute of Ophthalmology, University College London, London, UK.
- Department of Biological Structure, University of Washington, Seattle, WA, USA
| | | | - Anna Lebedeva
- Sainsbury Wellcome Centre, University College London, London, UK
| | - Michael Okun
- Centre for Systems Neuroscience and Department of Neuroscience, Psychology and Behaviour, University of Leicester, Leicester, UK
- UCL Queen Square Institute of Neurology, University College London, London, UK
| | - Marius Pachitariu
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA, USA
| | - Marius Bauza
- Sainsbury Wellcome Centre, University College London, London, UK
| | - Maxime Beau
- Wolfson Institute for Biomedical Research, University College London, London, UK
| | - Jai Bhagat
- UCL Queen Square Institute of Neurology, University College London, London, UK
| | - Claudia Böhm
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA, USA
| | | | - Susu Chen
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA, USA
| | - Jennifer Colonell
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA, USA
| | - Richard J Gardner
- Kavli Institute for Systems Neuroscience, Norwegian University of Science and Technology, Trondheim, Norway
| | - Bill Karsh
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA, USA
| | - Fabian Kloosterman
- Neuroelectronics Research Flanders, Leuven, Belgium
- IMEC, Leuven, Belgium
- Vlaams Instituut voor Biotechnologie (VIB), Leuven, Belgium
- Brain and Cognition, KU Leuven, Leuven, Belgium
| | - Dimitar Kostadinov
- Wolfson Institute for Biomedical Research, University College London, London, UK
| | | | | | - Junchol Park
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA, USA
| | | | - Britton Sauerbrei
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA, USA
| | - Rik J J van Daal
- ATLAS Neuroengineering, Leuven, Belgium
- Neuroelectronics Research Flanders, Leuven, Belgium
- Micro- and Nanosystems, KU Leuven, Leuven, Belgium
| | - Abraham Z Vollan
- Kavli Institute for Systems Neuroscience, Norwegian University of Science and Technology, Trondheim, Norway
| | | | | | - Zhiwen Ye
- Department of Biological Structure, University of Washington, Seattle, WA, USA
| | - Joshua T Dudman
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA, USA
| | | | - Adam W Hantman
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA, USA
| | - Kenneth D Harris
- UCL Queen Square Institute of Neurology, University College London, London, UK
| | - Albert K Lee
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA, USA
| | - Edvard I Moser
- Kavli Institute for Systems Neuroscience, Norwegian University of Science and Technology, Trondheim, Norway
| | - John O'Keefe
- Sainsbury Wellcome Centre, University College London, London, UK
| | | | - Karel Svoboda
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA, USA
| | - Michael Häusser
- Wolfson Institute for Biomedical Research, University College London, London, UK
| | - Sebastian Haesler
- Neuroelectronics Research Flanders, Leuven, Belgium
- Vlaams Instituut voor Biotechnologie (VIB), Leuven, Belgium
| | - Matteo Carandini
- UCL Institute of Ophthalmology, University College London, London, UK.
| | - Timothy D Harris
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA, USA.
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7
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Esquivelzeta Rabell J, Haesler S. Probing Olfaction in Space and Time. Neuron 2020; 108:228-230. [PMID: 33120020 DOI: 10.1016/j.neuron.2020.10.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
In this issue, Gill et al. apply holographic optogenetic stimulation in the olfactory bulb to control select neuronal ensembles in 3D. This approach allows them to dissociate the contribution of temporal spike features and spike rate to stimulus detection.
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Affiliation(s)
| | - Sebastian Haesler
- VIB, 3001 Leuven, Belgium; Imec, 3001 Leuven, Belgium; KU Leuven, Department of Neuroscience, Research Group Neurophysiology, 3000 Leuven, Belgium; Neuroelectronics Research Flanders, 3001 Leuven, Belgium.
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8
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Tarnaud T, Tanghe E, Haesler S, Lopez CM, Martens L, Joseph W. Investigation of the Stimulation Capabilities of a High-Resolution Neurorecording Probe for the Application of Closed-Loop Deep Brain Stimulation. Annu Int Conf IEEE Eng Med Biol Soc 2018; 2018:2166-2169. [PMID: 30440833 DOI: 10.1109/embc.2018.8512650] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Deep brain stimulation is an established surgical treatment for several neurological and movement disorders, such as Parkinson's disease, in which electrostimulation is applied to targeted deep nuclei in the basal ganglia through implanted electrode leads. Recent technological improvements in the field have focused on the theoretical advantage of current steering and adaptive (closed-loop) deep brain stimulation. Current steering between several active electrodes would allow for improved accuracy when targeting the desired brain structures. This has the additional benefit of avoiding undesired stimulation of neural tracts that are related to side effects, e.g., internal capsule fibres of passage in subthalamic nucleus deep brain stimulation. Closed-loop deep brain stimulation is based on the premise of continuous recording of a proxy for pathological neural activity (such as beta-band power of measured local field potentials in patients with Parkinson's disease) and accordingly adapting the used stimulus parameters. In this study, we investigate the suitability of an existing highresolution neurorecording probe for high-precision neurostimulation. If a subset of the probe's recording electrodes can be used for stimulation, then the probe would be a suitable candidate for closed-loop deep brain stimulation. A finiteelement model is used to calculate the electric potential, induced by current injection through the high-resolution probe, for different sets of active electrodes. Volumes of activated tissue are calculated and a comparison is made between the highresolution probe and a conventional stimulation lead. We investigate the capability of the probe to shift the volume of activated tissue by steering currents to different sets of active electrodes. Finally, safety limits for the injected current are used to determine the size of the volume in which neurons can be activated with the relatively small electrodes patches on the highresolution probe.
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9
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Libbrecht S, Hoffman L, Welkenhuysen M, Van den Haute C, Baekelandt V, Braeken D, Haesler S. Proximal and distal modulation of neural activity by spatially confined optogenetic activation with an integrated high-density optoelectrode. J Neurophysiol 2018; 120:149-161. [PMID: 29589813 DOI: 10.1152/jn.00888.2017] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Optogenetic manipulations are widely used for investigating the contribution of genetically identified cell types to behavior. Simultaneous electrophysiological recordings are less common, although they are critical for characterizing the specific impact of optogenetic manipulations on neural circuits in vivo. This is at least in part because combining photostimulation with large-scale electrophysiological recordings remains technically challenging, which also poses a limitation for performing extracellular identification experiments. Currently available interfaces that guide light of the appropriate wavelength into the brain combined with an electrophysiological modality suffer from various drawbacks such as a bulky size, low spatial resolution, heat dissipation, or photovoltaic artifacts. To address these challenges, we have designed and fabricated an integrated ultrathin neural interface with 12 optical outputs and 24 electrodes. We used the device to measure the effect of localized stimulation in the anterior olfactory cortex, a paleocortical structure involved in olfactory processing. Our experiments in adult mice demonstrate that because of its small dimensions, our novel tool causes far less tissue damage than commercially available devices. Moreover, optical stimulation and recording can be performed simultaneously, with no measurable electrical artifact during optical stimulation. Importantly, optical stimulation can be confined to small volumes with approximately single-cortical layer thickness. Finally, we find that even highly localized optical stimulation causes inhibition at more distant sites. NEW & NOTEWORTHY In this study, we establish a novel tool for simultaneous extracellular recording and optogenetic photostimulation. Because the device is built using established microchip technology, it can be fabricated with high reproducibility and reliability. We further show that even very localized stimulation affects neural firing far beyond the stimulation site. This demonstrates the difficulty in predicting circuit-level effects of optogenetic manipulations and highlights the importance of closely monitoring neural activity in optogenetic experiments.
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Affiliation(s)
- Sarah Libbrecht
- Laboratory for Neurobiology and Gene Therapy, Department of Neurosciences, KU Leuven, Leuven , Belgium
| | - Luis Hoffman
- Life Science Technologies and Imaging Department, Imec, Leuven , Belgium.,Neuroelectronics Research Flanders, Leuven , Belgium
| | | | - Chris Van den Haute
- Laboratory for Neurobiology and Gene Therapy, Department of Neurosciences, KU Leuven, Leuven , Belgium
| | - Veerle Baekelandt
- Laboratory for Neurobiology and Gene Therapy, Department of Neurosciences, KU Leuven, Leuven , Belgium
| | - Dries Braeken
- Life Science Technologies and Imaging Department, Imec, Leuven , Belgium
| | - Sebastian Haesler
- Research Group Neurophysiology, Department of Neurosciences, KU Leuven, Leuven , Belgium.,VIB, Leuven , Belgium.,Neuroelectronics Research Flanders, Leuven , Belgium
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10
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Mutlu K, Rabell JE, Martin Del Olmo P, Haesler S. IR thermography-based monitoring of respiration phase without image segmentation. J Neurosci Methods 2018; 301:1-8. [PMID: 29501561 DOI: 10.1016/j.jneumeth.2018.02.017] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2017] [Revised: 02/26/2018] [Accepted: 02/27/2018] [Indexed: 11/29/2022]
Abstract
BACKGROUND Respiratory rate is an essential parameter in biomedical research and clinical applications. Most respiration measurement techniques in preclinical animal models require surgical implantation of sensors. Current clinical measurement modalities typically involve attachment of sensors to the patient, causing discomfort. We have previously developed a non-contact approach to measuring respiration phase in head-restrained rodents using infrared (IR) thermography. While the non-invasive nature of IR thermography offers many advantages, it also bears the complexity of extracting respiration signals from videos. Previously reported algorithms involve image segmentation to identify the nose in IR videos and extract breathing-relevant pixels which is particularly challenging if the videos have low contrast or suffer from suboptimal focusing. NEW METHOD To address this challenge, we developed a novel algorithm, which extracts respiration signals based on pixel time series, removing the need for nose-tracking and image segmentation. RESULTS & COMPARISON WITH EXISTING METHODS We validated the algorithm by performing respiration measurements in head-restrained mice and in humans with IR thermography in parallel with established standard techniques. We find the algorithm reliably detects inhalation onsets with high temporal precision. CONCLUSIONS The new algorithm facilitates the application of IR thermography for measuring respiration in biomedical research and in clinical settings.
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Affiliation(s)
- K Mutlu
- Neuroelectronics Research Flanders, Leuven, Belgium; Department of Neurosciences, KU Leuven, Belgium
| | - J Esquivelzeta Rabell
- Neuroelectronics Research Flanders, Leuven, Belgium; Department of Neurosciences, KU Leuven, Belgium
| | | | - S Haesler
- Neuroelectronics Research Flanders, Leuven, Belgium; Department of Neurosciences, KU Leuven, Belgium; VIB, Leuven, Belgium; Imec, Leuven, Belgium.
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11
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Esquivelzeta Rabell J, Mutlu K, Noutel J, Martin Del Olmo P, Haesler S. Spontaneous Rapid Odor Source Localization Behavior Requires Interhemispheric Communication. Curr Biol 2017; 27:1542-1548.e4. [PMID: 28502658 DOI: 10.1016/j.cub.2017.04.027] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2016] [Revised: 03/14/2017] [Accepted: 04/14/2017] [Indexed: 12/14/2022]
Abstract
Navigation, finding food sources, and avoiding danger critically depend on the identification and spatial localization of airborne chemicals. When monitoring the olfactory environment, rodents spontaneously engage in active olfactory sampling behavior, also referred to as exploratory sniffing [1]. Exploratory sniffing is characterized by stereotypical high-frequency respiration, which is also reliably evoked by novel odorant stimuli [2, 3]. To study novelty-induced exploratory sniffing, we developed a novel, non-contact method for measuring respiration by infrared (IR) thermography in a behavioral paradigm in which novel and familiar stimuli are presented to head-restrained mice. We validated the method by simultaneously performing nasal pressure measurements, a commonly used invasive approach [2, 4], and confirmed highly reliable detection of inhalation onsets. We further discovered that mice actively orient their nostrils toward novel, previously unexperienced, smells. In line with the remarkable speed of olfactory processing reported previously [3, 5, 6], we find that mice initiate their response already within the first sniff after odor onset. Moreover, transecting the anterior commissure (AC) disrupted orienting, indicating that the orienting response requires interhemispheric transfer of information. This suggests that mice compare odorant information obtained from the two bilaterally symmetric nostrils to locate the source of the novel odorant. We further demonstrate that asymmetric activation of the anterior olfactory nucleus (AON) is both necessary and sufficient for eliciting orienting responses. These findings support the view that the AON plays an important role in the internostril difference comparison underlying rapid odor source localization.
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Affiliation(s)
- José Esquivelzeta Rabell
- Neuroelectronics Research Flanders, 3001 Leuven, Belgium; Department of Neurosciences, KU Leuven, 3001 Leuven, Belgium
| | - Kadir Mutlu
- Neuroelectronics Research Flanders, 3001 Leuven, Belgium; Department of Neurosciences, KU Leuven, 3001 Leuven, Belgium
| | - João Noutel
- Neuroelectronics Research Flanders, 3001 Leuven, Belgium; VIB, 3001 Leuven, Belgium
| | | | - Sebastian Haesler
- Neuroelectronics Research Flanders, 3001 Leuven, Belgium; Department of Neurosciences, KU Leuven, 3001 Leuven, Belgium; VIB, 3001 Leuven, Belgium; Imec, 3001 Leuven, Belgium.
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12
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Janse Van Rensburg A, Haesler S, Morrens J. The Function of Dopamine Novelty Responses in the Brain. Front Neurosci 2017. [DOI: 10.3389/conf.fnins.2017.94.00038] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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13
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Abstract
Technological advances have the potential to dramatically increase our understanding of the human brain, treat and cure injury and disease, and enhance our general well-being. While advances in neuroscience hold great promise, they also raise profound ethical, legal, and social questions. In this vein, the Organization for Economic Co-operation and Development (OECD) convened an international workshop in September 2016 to explore responsible research and innovation in brain science.
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Affiliation(s)
- Hermann Garden
- Science and Technology Policy Division, Directorate for Science, Technology and Innovation, OECD, 2, Rue André-Pascal, 75775 Paris Cedex 16, France.
| | - Diana M Bowman
- Sandra Day O'Connor College of Law and School for the Future of Innovation in Society, Arizona State University, Phoenix, AZ 85004, USA
| | - Sebastian Haesler
- Neuroelectronics Research Flanders, Kapeldreef 75, 3001 Leuven, Belgium
| | - David E Winickoff
- Science and Technology Policy Division, Directorate for Science, Technology and Innovation, OECD, 2, Rue André-Pascal, 75775 Paris Cedex 16, France
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14
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Neziri AY, Haesler S, Petersen-Felix S, Müller M, Arendt-Nielsen L, Manresa JB, Andersen OK, Curatolo M. Generalized expansion of nociceptive reflex receptive fields in chronic pain patients. Pain 2011; 151:798-805. [PMID: 20926191 DOI: 10.1016/j.pain.2010.09.017] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2010] [Revised: 08/09/2010] [Accepted: 09/13/2010] [Indexed: 11/18/2022]
Abstract
Widespread central hypersensitivity is present in chronic pain and contributes to pain and disability. According to animal studies, expansion of receptive fields of spinal cord neurons is involved in central hypersensitivity. We recently developed a method to quantify nociceptive receptive fields in humans using spinal withdrawal reflexes. Here we hypothesized that patients with chronic pelvic pain display enlarged reflex receptive fields. Secondary endpoints were subjective pain thresholds and nociceptive withdrawal reflex thresholds after single and repeated (temporal summation) electrical stimulation. 20 patients and 25 pain-free subjects were tested. Electrical stimuli were applied to 10 sites on the foot sole for evoking reflexes in the tibialis anterior muscle. The reflex receptive field was defined as the area of the foot (fraction of the foot sole) from which a muscle contraction was evoked. For the secondary endpoints, the stimuli were applied to the cutaneous innervation area of the sural nerve. Medians (25-75 percentiles) of fraction of the foot sole in patients and controls were 0.48 (0.38-0.54) and 0.33 (0.27-0.39), respectively (P=0.008). Pain and reflex thresholds after sural nerve stimulation were significantly lower in patients than in controls (P<0.001 for all measurements). This study provides for the first time evidence for widespread expansion of reflex receptive fields in chronic pain patients. It thereby identifies a mechanism involved in central hypersensitivity in human chronic pain. Reverting the expansion of nociceptive receptive fields and exploring the prognostic meaning of this phenomenon may become future targets of clinical research.
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Affiliation(s)
- Alban Y Neziri
- University Department of Anesthesiology and Pain Therapy, University Hospital of Bern, Inselspital, 3010 Bern, Switzerland University Department of Obstetrics and Gynecology, University Hospital of Bern, Inselspital, Bern, Switzerland Center for Sensory-Motor Interaction, Department of Health Science and Technology, Aalborg University, Denmark
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15
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Abstract
Mutations in the gene encoding the transcription factor FoxP2 impair human speech and language. We have previously shown that deficits in vocal learning occur in zebra finches after reduction of FoxP2 in Area X, a striatal nucleus involved in song acquisition. We recently showed that FoxP2 is expressed in newly generated spiny neurons (SN) in adult Area X as well as in the ventricular zone (VZ) from which the SN originates. Moreover, their recruitment to Area X increases transiently during the song learning phase. The present report therefore investigated whether FoxP2 is involved in the structural plasticity of Area X. We assessed the proliferation, differentiation and morphology of SN after lentivirally mediated knockdown of FoxP2 in Area X or in the VZ during the song learning phase. Proliferation rate was not significantly affected by knockdown of FoxP2 in the VZ. In addition, FoxP2 reduction both in the VZ and in Area X did not affect the number of new neurons in Area X. However, at the fine-structural level, SN in Area X bore fewer spines after FoxP2 knockdown. This effect was even more pronounced when neurons received the knockdown before differentiation, i.e. as neuroblasts in the VZ. These results suggest that FoxP2 might directly or indirectly regulate spine dynamics in Area X and thereby influence song plasticity. Together, these data present the first evidence for a role of FoxP2 in the structural plasticity of dendritic spines and complement the emerging evidence of physiological synaptic plasticity in FoxP2 mouse models.
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Affiliation(s)
- S B Schulz
- Freie Universität Berlin, Laboratory of Animal Behavior, Berlin, Germany
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16
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Wada K, Howard JT, McConnell P, Whitney O, Lints T, Rivas MV, Horita H, Patterson MA, White SA, Scharff C, Haesler S, Zhao S, Sakaguchi H, Hagiwara M, Shiraki T, Hirozane-Kishikawa T, Skene P, Hayashizaki Y, Carninci P, Jarvis ED. A molecular neuroethological approach for identifying and characterizing a cascade of behaviorally regulated genes. Proc Natl Acad Sci U S A 2006; 103:15212-7. [PMID: 17018643 PMCID: PMC1622802 DOI: 10.1073/pnas.0607098103] [Citation(s) in RCA: 154] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2006] [Indexed: 11/18/2022] Open
Abstract
Songbirds have one of the most accessible neural systems for the study of brain mechanisms of behavior. However, neuroethological studies in songbirds have been limited by the lack of high-throughput molecular resources and gene-manipulation tools. To overcome these limitations, we constructed 21 regular, normalized, and subtracted full-length cDNA libraries from brains of zebra finches in 57 developmental and behavioral conditions in an attempt to clone as much of the brain transcriptome as possible. From these libraries, approximately 14,000 transcripts were isolated, representing an estimated 4,738 genes. With the cDNAs, we created a hierarchically organized transcriptome database and a large-scale songbird brain cDNA microarray. We used the arrays to reveal a set of 33 genes that are regulated in forebrain vocal nuclei by singing behavior. These genes clustered into four anatomical and six temporal expression patterns. Their functions spanned a large range of cellular and molecular categories, from signal transduction, trafficking, and structural, to synaptically released molecules. With the full-length cDNAs and a lentiviral vector system, we were able to overexpress, in vocal nuclei, proteins of representative singing-regulated genes in the absence of singing. This publicly accessible resource http://songbirdtranscriptome.net can now be used to study molecular neuroethological mechanisms of behavior.
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Affiliation(s)
| | | | - Patrick McConnell
- Duke Bioinformatics Shared Resource, Duke University Medical Center, Durham, NC 27710
| | | | - Thierry Lints
- Department of Biology, City College of New York, New York, NY 10031
| | | | | | | | - Stephanie A. White
- Department of Physiological Science, University of California, Los Angeles, CA 90095
| | - Constance Scharff
- Neurobiology Group, Max Planck Institute for Molecular Genetics, 14195 Berlin, Germany
| | - Sebastian Haesler
- Neurobiology Group, Max Planck Institute for Molecular Genetics, 14195 Berlin, Germany
| | | | - Hironobu Sakaguchi
- **Department of Physiology and Biological Information, Dokkyo Medical University, Tochigi 321-0293, Japan
| | - Masatoshi Hagiwara
- Department of Functional Genomics, Tokyo Medical and Dental University, Tokyo 113-8519, Japan
| | - Toshiyuki Shiraki
- Genome Science Laboratory, RIKEN, Wako Main Campus, Saitama 351-0198, Japan; and
- Laboratory for Genome Exploration Research Group, RIKEN Yokohama Institute, Yokohama 230-0045, Japan
| | - Tomoko Hirozane-Kishikawa
- Genome Science Laboratory, RIKEN, Wako Main Campus, Saitama 351-0198, Japan; and
- Laboratory for Genome Exploration Research Group, RIKEN Yokohama Institute, Yokohama 230-0045, Japan
| | | | - Yoshihide Hayashizaki
- Genome Science Laboratory, RIKEN, Wako Main Campus, Saitama 351-0198, Japan; and
- Laboratory for Genome Exploration Research Group, RIKEN Yokohama Institute, Yokohama 230-0045, Japan
| | - Piero Carninci
- Genome Science Laboratory, RIKEN, Wako Main Campus, Saitama 351-0198, Japan; and
- Laboratory for Genome Exploration Research Group, RIKEN Yokohama Institute, Yokohama 230-0045, Japan
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Abstract
FoxP2 mutations in humans are associated with a disorder that affects both the comprehension of language and its production, speech. This discovery provided the first opportunity to analyze the genetics of language with molecular and neurobiological tools. The amino acid sequence and the neural expression pattern of FoxP2 are extremely conserved, from reptile to man. This suggests an important role for FoxP2 in vertebrate brains, regardless of whether they support imitative vocal learning or not. Its expression pattern pinpoints neural circuits that might have been crucial for the evolution of speech and language, including the basal ganglia and the cerebellum. Recent studies in songbirds show that during times of song plasticity FoxP2 is upregulated in a striatal region essential for song learning. This suggests that FoxP2 plays important roles both in the development of neural circuits and in the postnatal behaviors they mediate.
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Affiliation(s)
- Constance Scharff
- Max Planck Institute for Molecular Genetics, Ihnestrasse 73, 14195 Berlin, Germany; Freie Universität Berlin, Department of Animal Behavior, Grunewaldstrasse 34, 12165 Berlin, Germany.
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18
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Haesler S, Wada K, Nshdejan A, Morrisey EE, Lints T, Jarvis ED, Scharff C. FoxP2 expression in avian vocal learners and non-learners. J Neurosci 2004; 24:3164-75. [PMID: 15056696 PMCID: PMC6730012 DOI: 10.1523/jneurosci.4369-03.2004] [Citation(s) in RCA: 295] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2003] [Revised: 02/10/2004] [Accepted: 02/10/2004] [Indexed: 11/21/2022] Open
Abstract
Most vertebrates communicate acoustically, but few, among them humans, dolphins and whales, bats, and three orders of birds, learn this trait. FOXP2 is the first gene linked to human speech and has been the target of positive selection during recent primate evolution. To test whether the expression pattern of FOXP2 is consistent with a role in learned vocal communication, we cloned zebra finch FoxP2 and its close relative FoxP1 and compared mRNA and protein distribution in developing and adult brains of a variety of avian vocal learners and non-learners, and a crocodile. We found that the protein sequence of zebra finch FoxP2 is 98% identical with mouse and human FOXP2. In the avian and crocodilian forebrain, FoxP2 was expressed predominantly in the striatum, a basal ganglia brain region affected in patients with FOXP2 mutations. Strikingly, in zebra finches, the striatal nucleus Area X, necessary for vocal learning, expressed more FoxP2 than the surrounding tissue at post-hatch days 35 and 50, when vocal learning occurs. In adult canaries, FoxP2 expression in Area X differed seasonally; more FoxP2 expression was associated with times when song becomes unstable. In adult chickadees, strawberry finches, song sparrows, and Bengalese finches, Area X expressed FoxP2 to different degrees. Non-telencephalic regions in both vocal learning and non-learning birds, and in crocodiles, were less variable in expression and comparable with regions that express FOXP2 in human and rodent brains. We conclude that differential expression of FoxP2 in avian vocal learners might be associated with vocal plasticity.
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Kalscheuer VM, Freude K, Musante L, Jensen LR, Yntema HG, Gécz J, Sefiani A, Hoffmann K, Moser B, Haas S, Gurok U, Haesler S, Aranda B, Nshedjan A, Tzschach A, Hartmann N, Roloff TC, Shoichet S, Hagens O, Tao J, Van Bokhoven H, Turner G, Chelly J, Moraine C, Fryns JP, Nuber U, Hoeltzenbein M, Scharff C, Scherthan H, Lenzner S, Hamel BCJ, Schweiger S, Ropers HH. Mutations in the polyglutamine binding protein 1 gene cause X-linked mental retardation. Nat Genet 2003; 35:313-5. [PMID: 14634649 DOI: 10.1038/ng1264] [Citation(s) in RCA: 116] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2003] [Accepted: 10/31/2003] [Indexed: 11/08/2022]
Abstract
We found mutations in the gene PQBP1 in 5 of 29 families with nonsyndromic (MRX) and syndromic (MRXS) forms of X-linked mental retardation (XLMR). Clinical features in affected males include mental retardation, microcephaly, short stature, spastic paraplegia and midline defects. PQBP1 has previously been implicated in the pathogenesis of polyglutamine expansion diseases. Our findings link this gene to XLMR and shed more light on the pathogenesis of this common disorder.
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Affiliation(s)
- Vera M Kalscheuer
- Max-Planck-Institute for Molecular Genetics, Ihnestrasse 73, D-14195 Berlin, Germany.
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