1
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Rich PD, Thiberge SY, Scott BB, Guo C, Tervo DGR, Brody CD, Karpova AY, Daw ND, Tank DW. Magnetic voluntary head-fixation in transgenic rats enables lifespan imaging of hippocampal neurons. Nat Commun 2024; 15:4154. [PMID: 38755205 PMCID: PMC11099169 DOI: 10.1038/s41467-024-48505-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2023] [Accepted: 05/01/2024] [Indexed: 05/18/2024] Open
Abstract
The precise neural mechanisms within the brain that contribute to the remarkable lifetime persistence of memory are not fully understood. Two-photon calcium imaging allows the activity of individual cells to be followed across long periods, but conventional approaches require head-fixation, which limits the type of behavior that can be studied. We present a magnetic voluntary head-fixation system that provides stable optical access to the brain during complex behavior. Compared to previous systems that used mechanical restraint, there are no moving parts and animals can engage and disengage entirely at will. This system is failsafe, easy for animals to use and reliable enough to allow long-term experiments to be routinely performed. Animals completed hundreds of trials per session of an odor discrimination task that required 2-4 s fixations. Together with a reflectance fluorescence collection scheme that increases two-photon signal and a transgenic Thy1-GCaMP6f rat line, we are able to reliably image the cellular activity in the hippocampus during behavior over long periods (median 6 months), allowing us track the same neurons over a large fraction of animals' lives (up to 19 months).
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Affiliation(s)
- P Dylan Rich
- Princeton Neuroscience Institute, Princeton University, Princeton, NJ, USA.
| | | | - Benjamin B Scott
- Department of Psychological and Brain Sciences, Boston University, Boston, MA, USA
- Center for Systems Neuroscience, Boston University, Boston, MA, USA
- Neurophotonics Center, Boston University, Boston, MA, USA
| | - Caiying Guo
- Janelia Research Campus, Ashburn, VA, USA
- Howard Hughes Medical Institute, Ashburn, VA, USA
| | - D Gowanlock R Tervo
- Janelia Research Campus, Ashburn, VA, USA
- Howard Hughes Medical Institute, Ashburn, VA, USA
| | - Carlos D Brody
- Princeton Neuroscience Institute, Princeton University, Princeton, NJ, USA
- Howard Hughes Medical Institute, Princeton University, Princeton, NJ, USA
| | - Alla Y Karpova
- Janelia Research Campus, Ashburn, VA, USA
- Howard Hughes Medical Institute, Ashburn, VA, USA
| | - Nathaniel D Daw
- Princeton Neuroscience Institute, Princeton University, Princeton, NJ, USA
- Department of Psychology, Princeton University, Princeton, NJ, USA
| | - David W Tank
- Princeton Neuroscience Institute, Princeton University, Princeton, NJ, USA.
- Bezos Center for Neural Circuit Dynamics, Princeton University, Princeton, NJ, USA.
- Department of Molecular Biology, Princeton University, Princeton, NJ, USA.
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2
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Zhou ZC, Gordon-Fennell A, Piantadosi SC, Ji N, Smith SL, Bruchas MR, Stuber GD. Deep-brain optical recording of neural dynamics during behavior. Neuron 2023; 111:3716-3738. [PMID: 37804833 PMCID: PMC10843303 DOI: 10.1016/j.neuron.2023.09.006] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2023] [Revised: 08/24/2023] [Accepted: 09/06/2023] [Indexed: 10/09/2023]
Abstract
In vivo fluorescence recording techniques have produced landmark discoveries in neuroscience, providing insight into how single cell and circuit-level computations mediate sensory processing and generate complex behaviors. While much attention has been given to recording from cortical brain regions, deep-brain fluorescence recording is more complex because it requires additional measures to gain optical access to harder to reach brain nuclei. Here we discuss detailed considerations and tradeoffs regarding deep-brain fluorescence recording techniques and provide a comprehensive guide for all major steps involved, from project planning to data analysis. The goal is to impart guidance for new and experienced investigators seeking to use in vivo deep fluorescence optical recordings in awake, behaving rodent models.
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Affiliation(s)
- Zhe Charles Zhou
- Department of Anesthesiology and Pain Medicine, University of Washington, Seattle, WA 98195, USA; Center for Neurobiology of Addiction, Pain, and Emotion, University of Washington, Seattle, WA 98195, USA
| | - Adam Gordon-Fennell
- Department of Anesthesiology and Pain Medicine, University of Washington, Seattle, WA 98195, USA; Center for Neurobiology of Addiction, Pain, and Emotion, University of Washington, Seattle, WA 98195, USA
| | - Sean C Piantadosi
- Department of Anesthesiology and Pain Medicine, University of Washington, Seattle, WA 98195, USA; Center for Neurobiology of Addiction, Pain, and Emotion, University of Washington, Seattle, WA 98195, USA
| | - Na Ji
- Department of Physics, University of California, Berkeley, Berkeley, CA 94720, USA; Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA 94720, USA; Helen Wills Neuroscience Institute, University of California, Berkeley, Berkeley, CA 94720, USA; Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Spencer LaVere Smith
- Department of Electrical and Computer Engineering, University of California Santa Barbara, Santa Barbara, CA 93106, USA
| | - Michael R Bruchas
- Department of Anesthesiology and Pain Medicine, University of Washington, Seattle, WA 98195, USA; Center for Neurobiology of Addiction, Pain, and Emotion, University of Washington, Seattle, WA 98195, USA; Department of Pharmacology, University of Washington, Seattle, WA 98195, USA; Department of Bioengineering, University of Washington, Seattle, WA 98195, USA.
| | - Garret D Stuber
- Department of Anesthesiology and Pain Medicine, University of Washington, Seattle, WA 98195, USA; Center for Neurobiology of Addiction, Pain, and Emotion, University of Washington, Seattle, WA 98195, USA; Department of Pharmacology, University of Washington, Seattle, WA 98195, USA.
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3
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Zhang A, Zador AM. Neurons in the primary visual cortex of freely moving rats encode both sensory and non-sensory task variables. PLoS Biol 2023; 21:e3002384. [PMID: 38048367 PMCID: PMC10721203 DOI: 10.1371/journal.pbio.3002384] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2022] [Revised: 12/14/2023] [Accepted: 10/17/2023] [Indexed: 12/06/2023] Open
Abstract
Neurons in primary visual cortex (area V1) are strongly driven by both sensory stimuli and non-sensory events. However, although the representation of sensory stimuli has been well characterized, much less is known about the representation of non-sensory events. Here, we characterize the specificity and organization of non-sensory representations in rat V1 during a freely moving visual decision task. We find that single neurons encode diverse combinations of task features simultaneously and across task epochs. Despite heterogeneity at the level of single neuron response patterns, both visual and nonvisual task variables could be reliably decoded from small neural populations (5 to 40 units) throughout a trial. Interestingly, in animals trained to make an auditory decision following passive observation of a visual stimulus, some but not all task features could also be decoded from V1 activity. Our results support the view that even in V1-the earliest stage of the cortical hierarchy-bottom-up sensory information may be combined with top-down non-sensory information in a task-dependent manner.
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Affiliation(s)
- Anqi Zhang
- Cold Spring Harbor Laboratory, Cold Spring Harbor, New York, United States of America
- Cold Spring Harbor Laboratory School of Biological Sciences, Cold Spring Harbor, New York, United States of America
| | - Anthony M. Zador
- Cold Spring Harbor Laboratory, Cold Spring Harbor, New York, United States of America
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4
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Michelson NJ, Bolaños F, Bolaños LA, Balbi M, LeDue JM, Murphy TH. Meso-Py: Dual Brain Cortical Calcium Imaging in Mice during Head-Fixed Social Stimulus Presentation. eNeuro 2023; 10:ENEURO.0096-23.2023. [PMID: 38053472 PMCID: PMC10731520 DOI: 10.1523/eneuro.0096-23.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2023] [Revised: 11/06/2023] [Accepted: 11/14/2023] [Indexed: 12/07/2023] Open
Abstract
We present a cost-effective, compact foot-print, and open-source Raspberry Pi-based widefield imaging system. The compact nature allows the system to be used for close-proximity dual-brain cortical mesoscale functional-imaging to simultaneously observe activity in two head-fixed animals in a staged social touch-like interaction. We provide all schematics, code, and protocols for a rail system where head-fixed mice are brought together to a distance where the macrovibrissae of each mouse make contact. Cortical neuronal functional signals (GCaMP6s; genetically encoded Ca2+ sensor) were recorded from both mice simultaneously before, during, and after the social contact period. When the mice were together, we observed bouts of mutual whisking and cross-mouse correlated cortical activity across the cortex. Correlations were not observed in trial-shuffled mouse pairs, suggesting that correlated activity was specific to individual interactions. Whisking-related cortical signals were observed during the period where mice were together (closest contact). The effects of social stimulus presentation extend outside of regions associated with mutual touch and have global synchronizing effects on cortical activity.
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Affiliation(s)
- Nicholas J Michelson
- Department of Psychiatry, Kinsmen Laboratory of Neurological Research, University of British Columbia, Vancouver, British Columbia V6T 1Z3, Canada
- Djavad Mowafaghian Centre for Brain Health, University of British Columbia, Vancouver, British Columbia V6T 1Z3, Canada
| | - Federico Bolaños
- Department of Psychiatry, Kinsmen Laboratory of Neurological Research, University of British Columbia, Vancouver, British Columbia V6T 1Z3, Canada
- Djavad Mowafaghian Centre for Brain Health, University of British Columbia, Vancouver, British Columbia V6T 1Z3, Canada
| | - Luis A Bolaños
- Department of Psychiatry, Kinsmen Laboratory of Neurological Research, University of British Columbia, Vancouver, British Columbia V6T 1Z3, Canada
- Djavad Mowafaghian Centre for Brain Health, University of British Columbia, Vancouver, British Columbia V6T 1Z3, Canada
| | - Matilde Balbi
- Department of Psychiatry, Kinsmen Laboratory of Neurological Research, University of British Columbia, Vancouver, British Columbia V6T 1Z3, Canada
- Djavad Mowafaghian Centre for Brain Health, University of British Columbia, Vancouver, British Columbia V6T 1Z3, Canada
| | - Jeffrey M LeDue
- Department of Psychiatry, Kinsmen Laboratory of Neurological Research, University of British Columbia, Vancouver, British Columbia V6T 1Z3, Canada
- Djavad Mowafaghian Centre for Brain Health, University of British Columbia, Vancouver, British Columbia V6T 1Z3, Canada
| | - Timothy H Murphy
- Department of Psychiatry, Kinsmen Laboratory of Neurological Research, University of British Columbia, Vancouver, British Columbia V6T 1Z3, Canada
- Djavad Mowafaghian Centre for Brain Health, University of British Columbia, Vancouver, British Columbia V6T 1Z3, Canada
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5
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Hope J, Beckerle T, Cheng PH, Viavattine Z, Feldkamp M, Fausner S, Saxena K, Ko E, Hryb I, Carter R, Ebner T, Kodandaramaiah S. Brain-wide neural recordings in mice navigating physical spaces enabled by a cranial exoskeleton. RESEARCH SQUARE 2023:rs.3.rs-3491330. [PMID: 38014260 PMCID: PMC10680923 DOI: 10.21203/rs.3.rs-3491330/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2023]
Abstract
Complex behaviors are mediated by neural computations occurring throughout the brain. In recent years, tremendous progress has been made in developing technologies that can record neural activity at cellular resolution at multiple spatial and temporal scales. However, these technologies are primarily designed for studying the mammalian brain during head fixation - wherein the behavior of the animal is highly constrained. Miniaturized devices for studying neural activity in freely behaving animals are largely confined to recording from small brain regions owing to performance limitations. We present a cranial exoskeleton that assists mice in maneuvering neural recording headstages that are orders of magnitude larger and heavier than the mice, while they navigate physical behavioral environments. Force sensors embedded within the headstage are used to detect the mouse's milli-Newton scale cranial forces which then control the x, y, and yaw motion of the exoskeleton via an admittance controller. We discovered optimal controller tuning parameters that enable mice to locomote at physiologically realistic velocities and accelerations while maintaining natural walking gait. Mice maneuvering headstages weighing up to 1.5 kg can make turns, navigate 2D arenas, and perform a navigational decision-making task with the same performance as when freely behaving. We designed an imaging headstage and an electrophysiology headstage for the cranial exoskeleton to record brain-wide neural activity in mice navigating 2D arenas. The imaging headstage enabled recordings of Ca2+ activity of 1000s of neurons distributed across the dorsal cortex. The electrophysiology headstage supported independent control of up to 4 silicon probes, enabling simultaneous recordings from 100s of neurons across multiple brain regions and multiple days. Cranial exoskeletons provide flexible platforms for largescale neural recording during the exploration of physical spaces, a critical new paradigm for unraveling the brain-wide neural mechanisms that control complex behavior.
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Affiliation(s)
- James Hope
- Department of Mechanical Engineering, University of Minnesota, Twin Cities
| | - Travis Beckerle
- Department of Mechanical Engineering, University of Minnesota, Twin Cities
| | - Pin-Hao Cheng
- Department of Mechanical Engineering, University of Minnesota, Twin Cities
| | - Zoey Viavattine
- Department of Mechanical Engineering, University of Minnesota, Twin Cities
| | - Michael Feldkamp
- Department of Mechanical Engineering, University of Minnesota, Twin Cities
| | - Skylar Fausner
- Department of Mechanical Engineering, University of Minnesota, Twin Cities
| | - Kapil Saxena
- Department of Mechanical Engineering, University of Minnesota, Twin Cities
| | - Eunsong Ko
- Department of Mechanical Engineering, University of Minnesota, Twin Cities
| | - Ihor Hryb
- Department of Mechanical Engineering, University of Minnesota, Twin Cities
- Department of Neuroscience, University of Minnesota, Twin Cities
| | - Russell Carter
- Department of Biomedical Engineering, University of Minnesota, Twin Cities
| | - Timothy Ebner
- Department of Biomedical Engineering, University of Minnesota, Twin Cities
| | - Suhasa Kodandaramaiah
- Department of Mechanical Engineering, University of Minnesota, Twin Cities
- Department of Biomedical Engineering, University of Minnesota, Twin Cities
- Department of Neuroscience, University of Minnesota, Twin Cities
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6
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Kim SJ, Affan RO, Frostig H, Scott BB, Alexander AS. Advances in cellular resolution microscopy for brain imaging in rats. NEUROPHOTONICS 2023; 10:044304. [PMID: 38076724 PMCID: PMC10704261 DOI: 10.1117/1.nph.10.4.044304] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/05/2023] [Revised: 09/23/2023] [Accepted: 11/07/2023] [Indexed: 02/12/2024]
Abstract
Rats are used in neuroscience research because of their physiological similarities with humans and accessibility as model organisms, trainability, and behavioral repertoire. In particular, rats perform a wide range of sophisticated social, cognitive, motor, and learning behaviors within the contexts of both naturalistic and laboratory environments. Further progress in neuroscience can be facilitated by using advanced imaging methods to measure the complex neural and physiological processes during behavior in rats. However, compared with the mouse, the rat nervous system offers a set of challenges, such as larger brain size, decreased neuron density, and difficulty with head restraint. Here, we review recent advances in in vivo imaging techniques in rats with a special focus on open-source solutions for calcium imaging. Finally, we provide suggestions for both users and developers of in vivo imaging systems for rats.
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Affiliation(s)
- Su Jin Kim
- Johns Hopkins University, Department of Psychological and Brain Sciences, Baltimore, Maryland, United States
| | - Rifqi O. Affan
- Boston University, Center for Systems Neuroscience, Department of Psychological and Brain Sciences, Boston, Massachusetts, United States
- Boston University, Graduate Program in Neuroscience, Boston, Massachusetts, United States
| | - Hadas Frostig
- Boston University, Center for Systems Neuroscience, Department of Psychological and Brain Sciences, Boston, Massachusetts, United States
| | - Benjamin B. Scott
- Boston University, Center for Systems Neuroscience, Department of Psychological and Brain Sciences, Boston, Massachusetts, United States
- Boston University, Neurophotonics Center and Photonics Center, Boston, Massachusetts, United States
| | - Andrew S. Alexander
- University of California Santa Barbara, Department of Psychological and Brain Sciences, Santa Barbara, California, United States
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7
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Hope J, Beckerle T, Cheng PH, Viavattine Z, Feldkamp M, Fausner S, Saxena K, Ko E, Hryb I, Carter R, Ebner T, Kodandaramaiah S. Brain-wide neural recordings in mice navigating physical spaces enabled by a cranial exoskeleton. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.06.04.543578. [PMID: 37333228 PMCID: PMC10274744 DOI: 10.1101/2023.06.04.543578] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/20/2023]
Abstract
Complex behaviors are mediated by neural computations occurring throughout the brain. In recent years, tremendous progress has been made in developing technologies that can record neural activity at cellular resolution at multiple spatial and temporal scales. However, these technologies are primarily designed for studying the mammalian brain during head fixation - wherein the behavior of the animal is highly constrained. Miniaturized devices for studying neural activity in freely behaving animals are largely confined to recording from small brain regions owing to performance limitations. We present a cranial exoskeleton that assists mice in maneuvering neural recording headstages that are orders of magnitude larger and heavier than the mice, while they navigate physical behavioral environments. Force sensors embedded within the headstage are used to detect the mouse's milli-Newton scale cranial forces which then control the x, y, and yaw motion of the exoskeleton via an admittance controller. We discovered optimal controller tuning parameters that enable mice to locomote at physiologically realistic velocities and accelerations while maintaining natural walking gait. Mice maneuvering headstages weighing up to 1.5 kg can make turns, navigate 2D arenas, and perform a navigational decision-making task with the same performance as when freely behaving. We designed an imaging headstage and an electrophysiology headstage for the cranial exoskeleton to record brain-wide neural activity in mice navigating 2D arenas. The imaging headstage enabled recordings of Ca2+ activity of 1000s of neurons distributed across the dorsal cortex. The electrophysiology headstage supported independent control of up to 4 silicon probes, enabling simultaneous recordings from 100s of neurons across multiple brain regions and multiple days. Cranial exoskeletons provide flexible platforms for largescale neural recording during the exploration of physical spaces, a critical new paradigm for unraveling the brain-wide neural mechanisms that control complex behavior.
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Affiliation(s)
- James Hope
- Department of Mechanical Engineering, University of Minnesota, Twin Cities
| | - Travis Beckerle
- Department of Mechanical Engineering, University of Minnesota, Twin Cities
| | - Pin-Hao Cheng
- Department of Mechanical Engineering, University of Minnesota, Twin Cities
| | - Zoey Viavattine
- Department of Mechanical Engineering, University of Minnesota, Twin Cities
| | - Michael Feldkamp
- Department of Mechanical Engineering, University of Minnesota, Twin Cities
| | - Skylar Fausner
- Department of Mechanical Engineering, University of Minnesota, Twin Cities
| | - Kapil Saxena
- Department of Mechanical Engineering, University of Minnesota, Twin Cities
| | - Eunsong Ko
- Department of Mechanical Engineering, University of Minnesota, Twin Cities
| | - Ihor Hryb
- Department of Mechanical Engineering, University of Minnesota, Twin Cities
- Department of Neuroscience, University of Minnesota, Twin Cities
| | - Russell Carter
- Department of Biomedical Engineering, University of Minnesota, Twin Cities
| | - Timothy Ebner
- Department of Biomedical Engineering, University of Minnesota, Twin Cities
| | - Suhasa Kodandaramaiah
- Department of Mechanical Engineering, University of Minnesota, Twin Cities
- Department of Biomedical Engineering, University of Minnesota, Twin Cities
- Department of Neuroscience, University of Minnesota, Twin Cities
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8
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Wang Y, LeDue JM, Murphy TH. Multiscale imaging informs translational mouse modeling of neurological disease. Neuron 2022; 110:3688-3710. [PMID: 36198319 DOI: 10.1016/j.neuron.2022.09.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2022] [Revised: 05/26/2022] [Accepted: 09/06/2022] [Indexed: 11/05/2022]
Abstract
Multiscale neurophysiology reveals that simple motor actions are associated with changes in neuronal firing in virtually every brain region studied. Accordingly, the assessment of focal pathology such as stroke or progressive neurodegenerative diseases must also extend widely across brain areas. To derive mechanistic information through imaging, multiple resolution scales and multimodal factors must be included, such as the structure and function of specific neurons and glial cells and the dynamics of specific neurotransmitters. Emerging multiscale methods in preclinical animal studies that span micro- to macroscale examinations fill this gap, allowing a circuit-based understanding of pathophysiological mechanisms. Combined with high-performance computation and open-source data repositories, these emerging multiscale and large field-of-view techniques include live functional ultrasound, multi- and single-photon wide-scale light microscopy, video-based miniscopes, and tissue-penetrating fiber photometry, as well as variants of post-mortem expansion microscopy. We present these technologies and outline use cases and data pipelines to uncover new knowledge within animal models of stroke, Alzheimer's disease, and movement disorders.
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Affiliation(s)
- Yundi Wang
- University of British Columbia, Department of Psychiatry, Kinsmen Laboratory of Neurological Research, Detwiller Pavilion, 2255 Wesbrook Mall, Vancouver, BC V6T 1Z3, Canada; Djavad Mowafaghian Centre for Brain Health, University of British Columbia, 2215 Wesbrook Mall, Vancouver, BC V6T 1Z3, Canada
| | - Jeffrey M LeDue
- University of British Columbia, Department of Psychiatry, Kinsmen Laboratory of Neurological Research, Detwiller Pavilion, 2255 Wesbrook Mall, Vancouver, BC V6T 1Z3, Canada; Djavad Mowafaghian Centre for Brain Health, University of British Columbia, 2215 Wesbrook Mall, Vancouver, BC V6T 1Z3, Canada
| | - Timothy H Murphy
- University of British Columbia, Department of Psychiatry, Kinsmen Laboratory of Neurological Research, Detwiller Pavilion, 2255 Wesbrook Mall, Vancouver, BC V6T 1Z3, Canada; Djavad Mowafaghian Centre for Brain Health, University of British Columbia, 2215 Wesbrook Mall, Vancouver, BC V6T 1Z3, Canada.
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9
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Barkus C, Bergmann C, Branco T, Carandini M, Chadderton PT, Galiñanes GL, Gilmour G, Huber D, Huxter JR, Khan AG, King AJ, Maravall M, O'Mahony T, Ragan CI, Robinson ESJ, Schaefer AT, Schultz SR, Sengpiel F, Prescott MJ. Refinements to rodent head fixation and fluid/food control for neuroscience. J Neurosci Methods 2022; 381:109705. [PMID: 36096238 DOI: 10.1016/j.jneumeth.2022.109705] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2022] [Revised: 09/01/2022] [Accepted: 09/03/2022] [Indexed: 12/14/2022]
Abstract
The use of head fixation in mice is increasingly common in research, its use having initially been restricted to the field of sensory neuroscience. Head restraint has often been combined with fluid control, rather than food restriction, to motivate behaviour, but this too is now in use for both restrained and non-restrained animals. Despite this, there is little guidance on how best to employ these techniques to optimise both scientific outcomes and animal welfare. This article summarises current practices and provides recommendations to improve animal wellbeing and data quality, based on a survey of the community, literature reviews, and the expert opinion and practical experience of an international working group convened by the UK's National Centre for the Replacement, Refinement and Reduction of Animals in Research (NC3Rs). Topics covered include head fixation surgery and post-operative care, habituation to restraint, and the use of fluid/food control to motivate performance. We also discuss some recent developments that may offer alternative ways to collect data from large numbers of behavioural trials without the need for restraint. The aim is to provide support for researchers at all levels, animal care staff, and ethics committees to refine procedures and practices in line with the refinement principle of the 3Rs.
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Affiliation(s)
- Chris Barkus
- National Centre for Replacement, Refinement and Reduction of Animals in Research (NC3Rs), London, UK.
| | | | - Tiago Branco
- Sainsbury Wellcome Centre, University College London, London, UK
| | - Matteo Carandini
- Institute of Ophthalmology, University College London, London, UK
| | - Paul T Chadderton
- School of Physiology, Pharmacology and Neuroscience, University of Bristol, Bristol, UK
| | | | | | - Daniel Huber
- Department of Basic Neurosciences, University of Geneva, Geneva, Switzerland
| | | | - Adil G Khan
- Centre for Developmental Neurobiology, King's College London, London, UK
| | - Andrew J King
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, UK
| | - Miguel Maravall
- Sussex Neuroscience, School of Life Sciences, University of Sussex, Brighton, UK
| | - Tina O'Mahony
- Sainsbury Wellcome Centre, University College London, London, UK
| | - C Ian Ragan
- National Centre for Replacement, Refinement and Reduction of Animals in Research (NC3Rs), London, UK
| | - Emma S J Robinson
- School of Physiology, Pharmacology and Neuroscience, University of Bristol, Bristol, UK
| | - Andreas T Schaefer
- Sensory Circuits and Neurotechnology Laboratory, The Francis Crick Institute, London, UK; Department of Neuroscience, Physiology & Pharmacology, University College London, London, UK
| | - Simon R Schultz
- Centre for Neurotechnology and Department of Bioengineering, Imperial College London, London, UK
| | | | - Mark J Prescott
- National Centre for Replacement, Refinement and Reduction of Animals in Research (NC3Rs), London, UK
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10
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Bermudez Contreras E, Sutherland RJ, Mohajerani MH, Whishaw IQ. Challenges of a small world analysis for the continuous monitoring of behavior in mice. Neurosci Biobehav Rev 2022; 136:104621. [PMID: 35307475 DOI: 10.1016/j.neubiorev.2022.104621] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2021] [Revised: 02/14/2022] [Accepted: 03/11/2022] [Indexed: 12/18/2022]
Abstract
Documenting a mouse's "real world" behavior in the "small world" of a laboratory cage with continuous video recordings offers insights into phenotypical expression of mouse genotypes, development and aging, and neurological disease. Nevertheless, there are challenges in the design of a small world, the behavior selected for analysis, and the form of the analysis used. Here we offer insights into small world analyses by describing how acute behavioral procedures can guide continuous behavioral methodology. We show how algorithms can identify behavioral acts including walking and rearing, circadian patterns of action including sleep duration and waking activity, and the organization of patterns of movement into home base activity and excursions, and how they are altered with aging. We additionally describe how specific tests can be incorporated within a mouse's living arrangement. We emphasize how machine learning can condense and organize continuous activity that extends over extended periods of time.
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Affiliation(s)
| | - Robert J Sutherland
- Canadian Centre for Behavioural Neuroscience, University of Lethbridge, Canada
| | - Majid H Mohajerani
- Canadian Centre for Behavioural Neuroscience, University of Lethbridge, Canada.
| | - Ian Q Whishaw
- Canadian Centre for Behavioural Neuroscience, University of Lethbridge, Canada
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11
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Mouse tail skin wholemount staining and intravital calcium imaging. STAR Protoc 2022; 3:101235. [PMID: 35300002 PMCID: PMC8920931 DOI: 10.1016/j.xpro.2022.101235] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Mouse tail skin offers multiple benefits for skin research. Here, we present a protocol detailing high resolution tail skin whole mount staining and in vivo calcium imaging of hair follicle stem cells (HFSCs) using Sox9creERT2, GCaMP6s, and Ai14 mice. This approach enables the study of hair follicles and stem cells in different physiological and pathological conditions. The applications of the protocol include visualization of calcium signaling in other cell types with Cre/CreER lines or analyzing other cellular features with different reporter lines. For complete details on the use and execution of this protocol, please refer to Xie et al. (2022). High resolution whole mount immunofluorescent analysis of mouse hair follicle Intravital calcium imaging of hair follicle Applicable to other cell types or featuress with different driver and reporter lines
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12
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A miniature kinematic coupling device for mouse head fixation. J Neurosci Methods 2022; 372:109549. [DOI: 10.1016/j.jneumeth.2022.109549] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2021] [Revised: 02/22/2022] [Accepted: 02/26/2022] [Indexed: 11/18/2022]
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13
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Three Water Restriction Schedules Used in Rodent Behavioral Tasks Transiently Impair Growth and Differentially Evoke a Stress Hormone Response without Causing Dehydration. eNeuro 2021; 8:ENEURO.0424-21.2021. [PMID: 34815297 PMCID: PMC8672445 DOI: 10.1523/eneuro.0424-21.2021] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2021] [Revised: 11/13/2021] [Accepted: 11/17/2021] [Indexed: 11/21/2022] Open
Abstract
Water restriction is commonly used to motivate rodents to perform behavioral tasks; however, its effects on hydration and stress hormone levels are unknown. Here, we report daily body weight and bi-weekly packed red blood cell volume and corticosterone (CORT) in adult male rats across 80 days for three commonly used water restriction schedules. We also assessed renal adaptation to water restriction using postmortem histologic evaluation of renal medulla. A control group received ad libitum water. After one week of water restriction, rats on all restriction schedules resumed similar levels of growth relative to the control group. Normal hydration was observed, and water restriction did not drive renal adaptation. An intermittent restriction schedule was associated with an increase in CORT relative to the control group. However, intermittent restriction evokes a stress response which could affect behavioral and neurobiological results. Our results also suggest that stable motivation in behavioral tasks may only be achieved after one week of restriction.
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14
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Liu C, Li M, Wang R, Cui X, Jung H, Halin K, You H, Yang X, Chen W. Online Decoding System with Calcium Image From Mice Primary Motor Cortex. ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL INTERNATIONAL CONFERENCE 2021; 2021:6402-6405. [PMID: 34892577 DOI: 10.1109/embc46164.2021.9630138] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
With the development of calcium imaging, neuroscientists have been able to study neural activity with a higher spatial resolution. However, the real-time processing of calcium imaging is still a big challenge for future experiments and applications. Most neuroscientists have to process their imaging data offline due to the time-consuming of most existing calcium imaging analysis methods. We proposed a novel online neural signal processing framework for calcium imaging and established an Optical Brain-Computer Interface System (OBCIs) for decoding neural signals in real-time. We tested and evaluated this system by classifying the calcium signals obtained from the primary motor cortex of mice when the mice were performing a lever-pressing task. The performance of our online system could achieve above 80% in the average decoding accuracy. Our preliminary results show that the online neural processing framework could be applied to future closed-loop OBCIs studies.
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15
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Xie Y, Chen D, Jiang K, Song L, Qian N, Du Y, Yang Y, Wang F, Chen T. Hair shaft miniaturization causes stem cell depletion through mechanosensory signals mediated by a Piezo1-calcium-TNF-α axis. Cell Stem Cell 2021; 29:70-85.e6. [PMID: 34624205 DOI: 10.1016/j.stem.2021.09.009] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2021] [Revised: 07/19/2021] [Accepted: 09/13/2021] [Indexed: 12/17/2022]
Abstract
In aging, androgenic alopecia, and genetic hypotrichosis disorders, hair shaft miniaturization is often associated with hair follicle stem cell (HFSC) loss. However, the mechanism causing this stem cell depletion in vivo remains elusive. Here we show that hair shaft loss or a reduction in diameter shrinks the physical niche size, which results in mechanical compression of HFSCs and their apoptotic loss. Mechanistically, cell compression activates the mechanosensitive channel Piezo1, which triggers calcium influx. This confers tumor necrosis factor alpha (TNF-α) sensitivity in a hair-cycle-dependent manner in otherwise resistant HFSCs and induces ectopic apoptosis. Persistent hair shaft miniaturization during aging and genetic hypotrichosis disorders causes long-term HFSC loss by inducing continuous ectopic apoptosis through Piezo1. Our results identify an unconventional role of the inert hair shaft structure as a functional niche component governing HFSC survival and reveal a mechanosensory axis that regulates physical-niche-atrophy-induced stem cell depletion in vivo.
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Affiliation(s)
- Yuhua Xie
- China Agricultural University, Beijing, China; National Institute of Biological Sciences, Beijing, China
| | - Daoming Chen
- National Institute of Biological Sciences, Beijing, China
| | - Kaiju Jiang
- National Institute of Biological Sciences, Beijing, China
| | - Lifang Song
- National Institute of Biological Sciences, Beijing, China
| | - Nannan Qian
- National Institute of Biological Sciences, Beijing, China
| | - Yingxue Du
- National Institute of Biological Sciences, Beijing, China
| | - Yong Yang
- Institute of Dermatology, Chinese Academy of Medical Sciences and Peking Union Medical College, Nanjing, China
| | - Fengchao Wang
- National Institute of Biological Sciences, Beijing, China
| | - Ting Chen
- National Institute of Biological Sciences, Beijing, China; Tsinghua Institute of Multidisciplinary Biomedical Research, Tsinghua University, Beijing, China.
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16
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Hegedüs P, Velencei A, Belval CHD, Heckenast J, Hangya B. Training protocol for probabilistic Pavlovian conditioning in mice using an open-source head-fixed setup. STAR Protoc 2021; 2:100795. [PMID: 34522902 PMCID: PMC8424585 DOI: 10.1016/j.xpro.2021.100795] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
High throughput, temporally controlled, reproducible quantitative behavioral assays are important for understanding the neural mechanisms underlying behavior. Here, we provide a step-by-step training protocol for a probabilistic Pavlovian conditioning task, where two auditory cues predict probabilistic outcomes with different contingencies. This protocol allows us to study the differential behavioral and neuronal correlates of expected and surprising outcomes. It has been tested in combination with chronic in vivo electrophysiological recordings and optogenetic manipulations in ChAT-Cre and PV-Cre mouse lines. For complete details on the use and execution of this protocol, please refer to Hegedüs et al. (2021). We provide a training protocol for a probabilistic Pavlovian conditioning task in mice Two auditory cues predict probabilistic outcomes with different contingencies Possible to combine with chronic in vivo electrophysiology and optogenetics Ideal for testing behavioral and neural correlates of expected and surprising outcomes
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Affiliation(s)
- Panna Hegedüs
- Lendület Laboratory of Systems Neuroscience, Institute of Experimental Medicine, Budapest, Hungary.,János Szentágothai Doctoral School of Neurosciences, Semmelweis University, Budapest, Hungary
| | - Anna Velencei
- Lendület Laboratory of Systems Neuroscience, Institute of Experimental Medicine, Budapest, Hungary
| | - Claire-Hélène de Belval
- Lendület Laboratory of Systems Neuroscience, Institute of Experimental Medicine, Budapest, Hungary.,Interdisciplinary Masters' in Life Sciences, Ecole Normale Supérieure, Paris, France
| | - Julia Heckenast
- Lendület Laboratory of Systems Neuroscience, Institute of Experimental Medicine, Budapest, Hungary
| | - Balázs Hangya
- Lendület Laboratory of Systems Neuroscience, Institute of Experimental Medicine, Budapest, Hungary
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17
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Hao Y, Thomas AM, Li N. Fully autonomous mouse behavioral and optogenetic experiments in home-cage. eLife 2021; 10:e66112. [PMID: 33944781 PMCID: PMC8116056 DOI: 10.7554/elife.66112] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2020] [Accepted: 05/02/2021] [Indexed: 01/19/2023] Open
Abstract
Goal-directed behaviors involve distributed brain networks. The small size of the mouse brain makes it amenable to manipulations of neural activity dispersed across brain areas, but existing optogenetic methods serially test a few brain regions at a time, which slows comprehensive mapping of distributed networks. Laborious operant conditioning training required for most experimental paradigms exacerbates this bottleneck. We present an autonomous workflow to survey the involvement of brain regions at scale during operant behaviors in mice. Naive mice living in a home-cage system learned voluntary head-fixation (>1 hr/day) and performed difficult decision-making tasks, including contingency reversals, for 2 months without human supervision. We incorporated an optogenetic approach to manipulate activity in deep brain regions through intact skull during home-cage behavior. To demonstrate the utility of this approach, we tested dozens of mice in parallel unsupervised optogenetic experiments, revealing multiple regions in cortex, striatum, and superior colliculus involved in tactile decision-making.
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Affiliation(s)
- Yaoyao Hao
- Department of Neuroscience, Baylor College of MedicineHoustonUnited States
| | | | - Nuo Li
- Department of Neuroscience, Baylor College of MedicineHoustonUnited States
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18
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Lopes G, Monteiro P. New Open-Source Tools: Using Bonsai for Behavioral Tracking and Closed-Loop Experiments. Front Behav Neurosci 2021; 15:647640. [PMID: 33867952 PMCID: PMC8044343 DOI: 10.3389/fnbeh.2021.647640] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2020] [Accepted: 03/08/2021] [Indexed: 11/28/2022] Open
Abstract
The ability to dynamically control a behavioral task based on real-time animal behavior is an important feature for experimental neuroscientists. However, designing automated boxes for behavioral studies requires a coordinated combination of mechanical, electronic, and software design skills which can challenge even the best engineers, and for that reason used to be out of reach for the majority of experimental neurobiology and behavioral pharmacology researchers. Due to parallel advances in open-source hardware and software developed for neuroscience researchers, by neuroscience researchers, the landscape has now changed significantly. Here, we discuss powerful approaches to the study of behavior using examples and tutorials in the Bonsai visual programming language, towards designing simple neuroscience experiments that can help researchers immediately get started. This language makes it easy for researchers, even without programming experience, to combine the operation of several open-source devices in parallel and design their own integrated custom solutions, enabling unique and flexible approaches to the study of behavior, including video tracking of behavior and closed-loop electrophysiology.
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Affiliation(s)
| | - Patricia Monteiro
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, Braga, Portugal
- ICVS/3B’s–PT Government Associate Laboratory, Braga/Guimaraes, Portugal
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19
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Sosulina L, Mittag M, Geis HR, Hoffmann K, Klyubin I, Qi Y, Steffen J, Friedrichs D, Henneberg N, Fuhrmann F, Justus D, Keppler K, Cuello AC, Rowan MJ, Fuhrmann M, Remy S. Hippocampal hyperactivity in a rat model of Alzheimer's disease. J Neurochem 2021; 157:2128-2144. [PMID: 33583024 DOI: 10.1111/jnc.15323] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2020] [Revised: 01/19/2021] [Accepted: 01/31/2021] [Indexed: 12/21/2022]
Abstract
Neuronal network dysfunction is a hallmark of Alzheimer's disease (AD). However, the underlying pathomechanisms remain unknown. We analyzed the hippocampal micronetwork in transgenic McGill-R-Thy1-APP rats (APPtg) at the beginning of extracellular amyloid beta (Aβ) deposition. We established two-photon Ca2+ -imaging in vivo in the hippocampus of rats and found hyperactivity of CA1 neurons. Patch-clamp recordings in brain slices in vitro revealed increased neuronal input resistance and prolonged action potential width in CA1 pyramidal neurons. We did neither observe changes in synaptic inhibition, nor in excitation. Our data support the view that increased intrinsic excitability of CA1 neurons may precede inhibitory dysfunction at an early stage of Aβ-deposition and disease progression.
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Affiliation(s)
- Liudmila Sosulina
- Neuronal Networks Group, German Center for Neurodegenerative Diseases (DZNE), Bonn, Germany.,Department of Cellular Neuroscience, Leibniz Institute for Neurobiology, Magdeburg, Germany
| | - Manuel Mittag
- Neuroimmunology and Imaging Group, German Center for Neurodegenerative Diseases (DZNE), Bonn, Germany
| | - Hans-Rüdiger Geis
- Neuronal Networks Group, German Center for Neurodegenerative Diseases (DZNE), Bonn, Germany
| | - Kerstin Hoffmann
- Neuroimmunology and Imaging Group, German Center for Neurodegenerative Diseases (DZNE), Bonn, Germany
| | - Igor Klyubin
- Department of Pharmacology and Therapeutics, Trinity College, Dublin, Ireland
| | - Yingjie Qi
- Department of Pharmacology and Therapeutics, Trinity College, Dublin, Ireland
| | - Julia Steffen
- Neuroimmunology and Imaging Group, German Center for Neurodegenerative Diseases (DZNE), Bonn, Germany
| | - Detlef Friedrichs
- Neuronal Networks Group, German Center for Neurodegenerative Diseases (DZNE), Bonn, Germany
| | - Niklas Henneberg
- Neuronal Networks Group, German Center for Neurodegenerative Diseases (DZNE), Bonn, Germany
| | - Falko Fuhrmann
- Neuronal Networks Group, German Center for Neurodegenerative Diseases (DZNE), Bonn, Germany
| | - Daniel Justus
- Neuronal Networks Group, German Center for Neurodegenerative Diseases (DZNE), Bonn, Germany
| | - Kevin Keppler
- Light Microscopy Facility, German Center for Neurodegenerative Diseases (DZNE), Bonn, Germany
| | - A Claudio Cuello
- Department of Pharmacology and Therapeutics, McGill University, Montreal, QC, Canada
| | - Michael J Rowan
- Department of Pharmacology and Therapeutics, Trinity College, Dublin, Ireland
| | - Martin Fuhrmann
- Neuroimmunology and Imaging Group, German Center for Neurodegenerative Diseases (DZNE), Bonn, Germany
| | - Stefan Remy
- Neuronal Networks Group, German Center for Neurodegenerative Diseases (DZNE), Bonn, Germany.,Department of Cellular Neuroscience, Leibniz Institute for Neurobiology, Magdeburg, Germany
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20
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Causal Network Inference for Neural Ensemble Activity. Neuroinformatics 2021; 19:515-527. [PMID: 33393054 PMCID: PMC8233245 DOI: 10.1007/s12021-020-09505-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/03/2020] [Indexed: 11/11/2022]
Abstract
Interactions among cellular components forming a mesoscopic scale brain network (microcircuit) display characteristic neural dynamics. Analysis of microcircuits provides a system-level understanding of the neurobiology of health and disease. Causal discovery aims to detect causal relationships among variables based on observational data. A key barrier in causal discovery is the high dimensionality of the variable space. A method called Causal Inference for Microcircuits (CAIM) is proposed to reconstruct causal networks from calcium imaging or electrophysiology time series. CAIM combines neural recording, Bayesian network modeling, and neuron clustering. Validation experiments based on simulated data and a real-world reaching task dataset demonstrated that CAIM accurately revealed causal relationships among neural clusters.
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21
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Lee Y, Xie J, Lee E, Sudarsanan S, Lin DT, Chen R, Bhattacharyya SS. Real-Time Neuron Detection and Neural Signal Extraction Platform for Miniature Calcium Imaging. Front Comput Neurosci 2020; 14:43. [PMID: 32676021 PMCID: PMC7333463 DOI: 10.3389/fncom.2020.00043] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2019] [Accepted: 04/28/2020] [Indexed: 12/03/2022] Open
Abstract
Real-time neuron detection and neural activity extraction are critical components of real-time neural decoding. In this paper, we propose a novel real-time neuron detection and activity extraction system using a dataflow framework to provide real-time performance and adaptability to new algorithms and hardware platforms. The proposed system was evaluated on simulated calcium imaging data, calcium imaging data with manual annotation, and calcium imaging data of the anterior lateral motor cortex. We found that the proposed system accurately detected neurons and extracted neural activities in real time without any requirement for expensive, cumbersome, or special-purpose computing hardware. We expect that the system will enable cost-effective, real-time calcium imaging-based neural decoding, leading to precise neuromodulation.
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Affiliation(s)
- Yaesop Lee
- Department of Electrical and Computer Engineering, University of Maryland at College Park, College Park, MD, United States
| | - Jing Xie
- Department of Electrical and Computer Engineering, University of Maryland at College Park, College Park, MD, United States
| | - Eungjoo Lee
- Department of Electrical and Computer Engineering, University of Maryland at College Park, College Park, MD, United States
| | - Srijesh Sudarsanan
- Department of Electrical and Computer Engineering, University of Maryland at College Park, College Park, MD, United States
| | - Da-Ting Lin
- National Institute on Drug Abuse, National Institutes of Health (NIH), Baltimore, MD, United States
| | - Rong Chen
- Department of Electrical and Computer Engineering, University of Maryland at College Park, College Park, MD, United States.,Department of Diagnostic Radiology and Nuclear Medicine, University of Maryland at Baltimore, Baltimore, MD, United States
| | - Shuvra S Bhattacharyya
- Department of Electrical and Computer Engineering, University of Maryland at College Park, College Park, MD, United States.,Institute for Advanced Computer Studies (UMIACS), University of Maryland at College Park, College Park, MD, United States
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22
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Murphy TH, Michelson NJ, Boyd JD, Fong T, Bolanos LA, Bierbrauer D, Siu T, Balbi M, Bolanos F, Vanni M, LeDue JM. Automated task training and longitudinal monitoring of mouse mesoscale cortical circuits using home cages. eLife 2020; 9:55964. [PMID: 32412409 PMCID: PMC7332290 DOI: 10.7554/elife.55964] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2020] [Accepted: 05/07/2020] [Indexed: 12/12/2022] Open
Abstract
We report improved automated open-source methodology for head-fixed mesoscale cortical imaging and/or behavioral training of home cage mice using Raspberry Pi-based hardware. Staged partial and probabilistic restraint allows mice to adjust to self-initiated headfixation over 3 weeks' time with ~50% participation rate. We support a cue-based behavioral licking task monitored by a capacitive touch-sensor water spout. While automatically head-fixed, we acquire spontaneous, movement-triggered, or licking task-evoked GCaMP6 cortical signals. An analysis pipeline marked both behavioral events, as well as analyzed brain fluorescence signals as they relate to spontaneous and/or task-evoked behavioral activity. Mice were trained to suppress licking and wait for cues that marked the delivery of water. Correct rewarded go-trials were associated with widespread activation of midline and lateral barrel cortex areas following a vibration cue and delayed frontal and lateral motor cortex activation. Cortical GCaMP signals predicted trial success and correlated strongly with trial-outcome dependent body movements.
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Affiliation(s)
- Timothy H Murphy
- Department of Psychiatry, Kinsmen Laboratory of Neurological Research, Vancouver, Canada.,Djavad Mowafaghian Centre for Brain Health, University of British Columbia, Vancouver, Canada
| | - Nicholas J Michelson
- Department of Psychiatry, Kinsmen Laboratory of Neurological Research, Vancouver, Canada.,Djavad Mowafaghian Centre for Brain Health, University of British Columbia, Vancouver, Canada
| | - Jamie D Boyd
- Department of Psychiatry, Kinsmen Laboratory of Neurological Research, Vancouver, Canada.,Djavad Mowafaghian Centre for Brain Health, University of British Columbia, Vancouver, Canada
| | - Tony Fong
- Department of Psychiatry, Kinsmen Laboratory of Neurological Research, Vancouver, Canada.,Djavad Mowafaghian Centre for Brain Health, University of British Columbia, Vancouver, Canada
| | - Luis A Bolanos
- Department of Psychiatry, Kinsmen Laboratory of Neurological Research, Vancouver, Canada.,Djavad Mowafaghian Centre for Brain Health, University of British Columbia, Vancouver, Canada
| | - David Bierbrauer
- Department of Psychiatry, Kinsmen Laboratory of Neurological Research, Vancouver, Canada.,Djavad Mowafaghian Centre for Brain Health, University of British Columbia, Vancouver, Canada
| | - Teri Siu
- Department of Psychiatry, Kinsmen Laboratory of Neurological Research, Vancouver, Canada.,Djavad Mowafaghian Centre for Brain Health, University of British Columbia, Vancouver, Canada
| | - Matilde Balbi
- Department of Psychiatry, Kinsmen Laboratory of Neurological Research, Vancouver, Canada.,Djavad Mowafaghian Centre for Brain Health, University of British Columbia, Vancouver, Canada
| | - Federico Bolanos
- Department of Psychiatry, Kinsmen Laboratory of Neurological Research, Vancouver, Canada.,Djavad Mowafaghian Centre for Brain Health, University of British Columbia, Vancouver, Canada
| | - Matthieu Vanni
- Department of Psychiatry, Kinsmen Laboratory of Neurological Research, Vancouver, Canada.,Djavad Mowafaghian Centre for Brain Health, University of British Columbia, Vancouver, Canada
| | - Jeff M LeDue
- Department of Psychiatry, Kinsmen Laboratory of Neurological Research, Vancouver, Canada.,Djavad Mowafaghian Centre for Brain Health, University of British Columbia, Vancouver, Canada
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23
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Walker JD, Pirschel F, Gidmark N, MacLean JN, Hatsopoulos NG. A platform for semiautomated voluntary training of common marmosets for behavioral neuroscience. J Neurophysiol 2020; 123:1420-1426. [PMID: 32130092 PMCID: PMC7191516 DOI: 10.1152/jn.00300.2019] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2019] [Revised: 02/28/2020] [Accepted: 02/28/2020] [Indexed: 01/31/2023] Open
Abstract
Generally behavioral neuroscience studies of the common marmoset employ adaptations of well-established training methods used with macaque monkeys. However, in many cases these approaches do not readily generalize to marmosets indicating a need for alternatives. Here we present the development of one such alternate: a platform for semiautomated, voluntary in-home cage behavioral training that allows for the study of naturalistic behaviors. We describe the design and production of a modular behavioral training apparatus using CAD software and digital fabrication. We demonstrate that this apparatus permits voluntary behavioral training and data collection throughout the marmoset's waking hours with little experimenter intervention. Furthermore, we demonstrate the use of this apparatus to reconstruct the kinematics of the marmoset's upper limb movement during natural foraging behavior.NEW & NOTEWORTHY The study of marmosets in neuroscience has grown rapidly and presents unique challenges. We address those challenges with an innovative platform for semiautomated, voluntary training that allows marmosets to train throughout their waking hours with minimal experimenter intervention. We describe the use of this platform to capture upper limb kinematics during foraging and to expand the opportunities for behavioral training beyond the limits of traditional training sessions. This flexible platform can easily incorporate other tasks.
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Affiliation(s)
- Jeffrey D Walker
- Committee on Computational Neuroscience, University of Chicago, Chicago, Illinois
- Department of Organismal Biology and Anatomy, University of Chicago, Chicago, Illinois
| | - Friederice Pirschel
- Department of Organismal Biology and Anatomy, University of Chicago, Chicago, Illinois
| | | | - Jason N MacLean
- Committee on Computational Neuroscience, University of Chicago, Chicago, Illinois
- Department of Neurobiology, University of Chicago, Chicago, Illinois
- Grossman Institute for Neuroscience, Quantitative Biology and Human Behavior, University of Chicago, Chicago, Illinois
| | - Nicholas G Hatsopoulos
- Committee on Computational Neuroscience, University of Chicago, Chicago, Illinois
- Department of Organismal Biology and Anatomy, University of Chicago, Chicago, Illinois
- Grossman Institute for Neuroscience, Quantitative Biology and Human Behavior, University of Chicago, Chicago, Illinois
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24
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Reinert JK, Schaefer AT, Kuner T. High-Throughput Automated Olfactory Phenotyping of Group-Housed Mice. Front Behav Neurosci 2019; 13:267. [PMID: 31920577 PMCID: PMC6927946 DOI: 10.3389/fnbeh.2019.00267] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2019] [Accepted: 11/25/2019] [Indexed: 11/13/2022] Open
Abstract
Behavioral phenotyping of mice is often compromised by manual interventions of the experimenter and limited throughput. Here, we describe a fully automated behavior setup that allows for quantitative analysis of mouse olfaction with minimized experimenter involvement. Mice are group-housed and tagged with unique RFID chips. They can freely initiate trials and are automatically trained on a go/no-go task, learning to distinguish a rewarded from an unrewarded odor. Further, odor discrimination tasks and detailed training aspects can be set for each animal individually for automated execution without direct experimenter intervention. The procedure described here, from initial RFID implantation to discrimination of complex odor mixtures at high accuracy, can be completed within <2 months with cohorts of up to 25 male mice. Apart from the presentation of monomolecular odors, the setup can generate arbitrary mixtures and dilutions from any set of odors to create complex stimuli, enabling demanding behavioral analyses at high-throughput.
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Affiliation(s)
- Janine K. Reinert
- Institute of Anatomy and Cell Biology, Heidelberg University, Heidelberg, Germany
| | - Andreas T. Schaefer
- Institute of Anatomy and Cell Biology, Heidelberg University, Heidelberg, Germany
- Neurophysiology of Behaviour Laboratory, The Francis Crick Institute, London, United Kingdom
- Department of Neuroscience, Physiology and Pharmacology, University College London, London, United Kingdom
| | - Thomas Kuner
- Institute of Anatomy and Cell Biology, Heidelberg University, Heidelberg, Germany
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25
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Scida K, Plaxco KW, Jamieson BG. High frequency, real-time neurochemical and neuropharmacological measurements in situ in the living body. Transl Res 2019; 213:50-66. [PMID: 31361988 DOI: 10.1016/j.trsl.2019.07.004] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/28/2019] [Revised: 05/20/2019] [Accepted: 07/11/2019] [Indexed: 12/18/2022]
Abstract
The beautiful and complex brain machinery is perfectly synchronized, and our bodies have evolved to protect it against a myriad of potential threats. Shielded physically by the skull and chemically by the blood brain barrier, the brain processes internal and external information so that we can efficiently relate to the world that surrounds us while simultaneously and unconsciously controlling our vital functions. When coupled with the brittle nature of its internal chemical and electric signals, the brain's "armor" render accessing it a challenging and delicate endeavor that has historically limited our understanding of its structural and neurochemical intricacies. In this review, we briefly summarize the advancements made over the past 10 years to decode the brain's neurochemistry and neuropharmacology in situ, at the site of interest in the brain, with special focus on what we consider game-changing emerging technologies (eg, genetically encoded indicators and electrochemical aptamer-based sensors) and the challenges these must overcome before chronic, in situ chemosensing measurements become routine.
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Affiliation(s)
- Karen Scida
- Diagnostic Biochips, Inc., Glen Burnie, Maryland
| | - Kevin W Plaxco
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, California
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26
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Koletar MM, Dorr A, Brown ME, McLaurin J, Stefanovic B. Refinement of a chronic cranial window implant in the rat for longitudinal in vivo two-photon fluorescence microscopy of neurovascular function. Sci Rep 2019; 9:5499. [PMID: 30940849 PMCID: PMC6445076 DOI: 10.1038/s41598-019-41966-9] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2018] [Accepted: 03/19/2019] [Indexed: 12/13/2022] Open
Abstract
Longitudinal studies using two–photon fluorescence microscopy (TPFM) are critical for facilitating cellular scale imaging of brain morphology and function. Studies have been conducted in the mouse due to their relatively higher transparency and long term patency of a chronic cranial window. Increasing availability of transgenic rat models, and the range of established behavioural paradigms, necessitates development of a chronic preparation for the rat. However, surgical craniotomies in the rat present challenges due to craniotomy closure by wound healing and diminished image quality due to inflammation, restricting most rat TPFM experiments to acute preparations. Long-term patency is enabled by employing sterile surgical technique, minimization of trauma with precise tissue handling during surgery, judicious selection of the size and placement of the craniotomy, diligent monitoring of animal physiology and support throughout the surgery, and modification of the home cage for long-term preservation of cranial implants. Immunohistochemical analysis employing the glial fibrillary acidic protein (GFAP) and ionized calcium-binding adaptor molecule-1 (Iba-1) showed activation and recruitment of astrocytes and microglia/macrophages directly inferior to the cranial window at one week after surgery, with more diffuse response in deeper cortical layers at two weeks, and amelioration around four weeks post craniotomy. TPFM was conducted up to 14 weeks post craniotomy, reaching cortical depths of 400 µm to 600 µm at most time-points. The rate of signal decay with increasing depth and maximum cortical depth attained had greater variation between individual rats at a single time-point than within a rat across time.
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Affiliation(s)
- Margaret M Koletar
- Sunnybrook Research Institute, 2075 Bayview Avenue, Toronto, Ontario, M4N 3M5, Canada.
| | - Adrienne Dorr
- Sunnybrook Research Institute, 2075 Bayview Avenue, Toronto, Ontario, M4N 3M5, Canada
| | - Mary E Brown
- Sunnybrook Research Institute, 2075 Bayview Avenue, Toronto, Ontario, M4N 3M5, Canada
| | - JoAnne McLaurin
- Sunnybrook Research Institute, 2075 Bayview Avenue, Toronto, Ontario, M4N 3M5, Canada.,Department of Laboratory Medicine and Pathobiology, University of Toronto, 1 King's College Circle, Toronto, Ontario, M5S 1A1, Canada
| | - Bojana Stefanovic
- Department of Medical Biophysics, University of Toronto, 610 University Avenue, Toronto, Ontario, M5G 2M9, Canada.,Sunnybrook Research Institute, 2075 Bayview Avenue, Toronto, Ontario, M4N 3M5, Canada
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27
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Erskine A, Bus T, Herb JT, Schaefer AT. AutonoMouse: High throughput operant conditioning reveals progressive impairment with graded olfactory bulb lesions. PLoS One 2019; 14:e0211571. [PMID: 30840676 PMCID: PMC6402634 DOI: 10.1371/journal.pone.0211571] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2018] [Accepted: 01/16/2019] [Indexed: 11/18/2022] Open
Abstract
Operant conditioning is a crucial tool in neuroscience research for probing brain function. While molecular, anatomical and even physiological techniques have seen radical increases in throughput, efficiency, and reproducibility in recent years, behavioural tools have somewhat lagged behind. Here we present a fully automated, high-throughput system for self-initiated conditioning of up to 25 group-housed, radio-frequency identification (RFID) tagged mice over periods of several months and >106 trials. We validate this "AutonoMouse" system in a series of olfactory behavioural tasks and show that acquired data is comparable to previous semi-manual approaches. Furthermore, we use AutonoMouse to systematically probe the impact of graded olfactory bulb lesions on olfactory behaviour, demonstrating that while odour discrimination in general is robust to even most extensive disruptions, small olfactory bulb lesions already impair odour detection. Discrimination learning of similar mixtures as well as learning speed are in turn reliably impacted by medium lesion sizes. The modular nature and open-source design of AutonoMouse should allow for similar robust and systematic assessments across neuroscience research areas.
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Affiliation(s)
- Andrew Erskine
- The Francis Crick Institute, Neurophysiology of Behaviour Laboratory, London, United Kingdom
- Department of Neuroscience, Physiology & Pharmacology, University College London, London, United Kingdom
| | - Thorsten Bus
- Behavioural Neurophysiology, Max-Planck-Institute for Medical Research, Heidelberg, Germany
| | - Jan T. Herb
- The Francis Crick Institute, Neurophysiology of Behaviour Laboratory, London, United Kingdom
- Behavioural Neurophysiology, Max-Planck-Institute for Medical Research, Heidelberg, Germany
- Department of Anatomy and Cell Biology, Faculty of Medicine, University of Heidelberg, Heidelberg, Germany
| | - Andreas T. Schaefer
- The Francis Crick Institute, Neurophysiology of Behaviour Laboratory, London, United Kingdom
- Department of Neuroscience, Physiology & Pharmacology, University College London, London, United Kingdom
- Behavioural Neurophysiology, Max-Planck-Institute for Medical Research, Heidelberg, Germany
- Department of Anatomy and Cell Biology, Faculty of Medicine, University of Heidelberg, Heidelberg, Germany
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28
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Lin X, Zhao T, Xiong W, Wen S, Jin X, Xu XM. Imaging Neural Activity in the Primary Somatosensory Cortex Using Thy1-GCaMP6s Transgenic Mice. J Vis Exp 2019. [PMID: 30663664 DOI: 10.3791/56297] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022] Open
Abstract
The mammalian brain exhibits marked symmetry across the sagittal plane. However, detailed description of neural dynamics in symmetric brain regions in adult mammalian animals remains elusive. In this study, we describe an experimental procedure for measuring calcium dynamics through dual optical windows above bilateral primary somatosensory corticies (S1) in Thy1-GCaMP6s transgenic mice using 2-photon (2P) microscopy. This method enables recordings and quantifications of neural activity in bilateral mouse brain regions one at a time in the same experiment for a prolonged period in vivo. Key aspects of this method, which can be completed within an hour, include minimally invasive surgery procedures for creating dual optical windows, and the use of 2P imaging. Although we only demonstrate the technique in the S1 area, the method can be applied to other regions of the living brain facilitating the elucidation of structural and functional complexities of brain neural networks.
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Affiliation(s)
- Xiaojing Lin
- Spinal Cord and Brain Injury Research Group, Stark Neurosciences Research Institute, Department of Neurological Surgery and Goodman and Campbell Brain and Spine, Department of Anatomy and Cell Biology, Indiana University School of Medicine; Department of Spinal Cord Injury and Repair, Trauma and Orthopedics Institute of Chinese PLA, General Hospital of Jinan Military Region
| | - Tingbao Zhao
- Department of Orthopedics, Shandong Cancer Hospital, Shandong University
| | - Wenhui Xiong
- Spinal Cord and Brain Injury Research Group, Stark Neurosciences Research Institute, Department of Neurological Surgery and Goodman and Campbell Brain and Spine, Department of Anatomy and Cell Biology, Indiana University School of Medicine
| | - Shaonan Wen
- Department of Neurobiology, Institute of Basic Medical Sciences, Academy Military Medical Sciences
| | - Xiaoming Jin
- Spinal Cord and Brain Injury Research Group, Stark Neurosciences Research Institute, Department of Neurological Surgery and Goodman and Campbell Brain and Spine, Department of Anatomy and Cell Biology, Indiana University School of Medicine
| | - Xiao-Ming Xu
- Spinal Cord and Brain Injury Research Group, Stark Neurosciences Research Institute, Department of Neurological Surgery and Goodman and Campbell Brain and Spine, Department of Anatomy and Cell Biology, Indiana University School of Medicine;
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29
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Imaging Cortical Dynamics in GCaMP Transgenic Rats with a Head-Mounted Widefield Macroscope. Neuron 2018; 100:1045-1058.e5. [PMID: 30482694 DOI: 10.1016/j.neuron.2018.09.050] [Citation(s) in RCA: 87] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2017] [Revised: 08/03/2018] [Accepted: 09/27/2018] [Indexed: 01/01/2023]
Abstract
Widefield imaging of calcium dynamics is an emerging method for mapping regional neural activity but is currently limited to restrained animals. Here we describe cScope, a head-mounted widefield macroscope developed to image large-scale cortical dynamics in rats during natural behavior. cScope provides a 7.8 × 4 mm field of view and dual illumination paths for both fluorescence and hemodynamic correction and can be fabricated at low cost using readily attainable components. We also report the development of Thy-1 transgenic rat strains with widespread neuronal expression of the calcium indicator GCaMP6f. We combined these two technologies to image large-scale calcium dynamics in the dorsal neocortex during a visual evidence accumulation task. Quantitative analysis of task-related dynamics revealed multiple regions having neural signals that encode behavioral choice and sensory evidence. Our results provide a new transgenic resource for calcium imaging in rats and extend the domain of head-mounted microscopes to larger-scale cortical dynamics. VIDEO ABSTRACT.
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30
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Schriver BJ, Bagdasarov S, Wang Q. Pupil-linked arousal modulates behavior in rats performing a whisker deflection direction discrimination task. J Neurophysiol 2018; 120:1655-1670. [PMID: 29995602 PMCID: PMC6230792 DOI: 10.1152/jn.00290.2018] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2018] [Revised: 07/09/2018] [Accepted: 07/09/2018] [Indexed: 11/22/2022] Open
Abstract
Non-luminance-mediated changes in pupil size have been widely used to index arousal state. Recent animal studies have demonstrated correlations between behavioral state-related pupil dynamics and sensory processing. However, the relationship between pupil-linked arousal and behavior in animals performing perceptual tasks has not been fully elucidated. In the present study, we trained head-fixed rats to discriminate between directions of whisker movements using a Go/No-Go discrimination paradigm while imaging their pupils. Reaction times in this discrimination task were significantly slower than in previously reported detection tasks with similar setup, suggesting that discrimination required an increased cognitive load. We found the pupils dilated for all trials following stimulus presentation. Interestingly, in correct rejection trials, where pupil dilations solely resulted from cognitive processing, dilations were larger for more difficult stimuli. Baseline pupil size before stimulus presentation strongly correlated with behavior, as perceptual sensitivity peaked at intermediate pupil baselines and reaction time was fastest at large baselines. We further explored these relationships by investigating to what extent pupil baseline was predictive of upcoming behavior and found that a Bayesian decoder had significantly greater-than-chance probability in correctly predicting behavioral outcomes. Moreover, the outcome of the previous trial showed a strong correlation with behavior on present trials. Animals were more liberal and faster in responding following hit trials, whereas perceptual sensitivity was greatest following correct rejection trials. Taken together, these results suggest a tight correlation between pupil dynamics, perceptual performance, and reaction time in behaving rats, all of which are modulated by fluctuating arousal state. NEW & NOTEWORTHY In this study, we for the first time demonstrated that head-fixed rats were able to discriminate different directions of whisker movement. Interestingly, we found that the pupil dilated more when discriminating more difficult stimuli, a phenomenon reported in human subjects but not in animals. Baseline pupil size before stimulus presentation was found to strongly correlate with behavior, and a Bayesian decoder had significantly greater-than-chance probability in correctly predicting behavioral outcomes based on the baseline pupil size.
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Affiliation(s)
- Brian J Schriver
- Department of Biomedical Engineering, Columbia University , New York, New York
| | - Svetlana Bagdasarov
- Department of Biomedical Engineering, Columbia University , New York, New York
| | - Qi Wang
- Department of Biomedical Engineering, Columbia University , New York, New York
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31
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32
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Goltstein PM, Reinert S, Glas A, Bonhoeffer T, Hübener M. Food and water restriction lead to differential learning behaviors in a head-fixed two-choice visual discrimination task for mice. PLoS One 2018; 13:e0204066. [PMID: 30212542 PMCID: PMC6136814 DOI: 10.1371/journal.pone.0204066] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2018] [Accepted: 08/31/2018] [Indexed: 12/11/2022] Open
Abstract
Head-fixed behavioral tasks can provide important insights into cognitive processes in rodents. Despite the widespread use of this experimental approach, there is only limited knowledge of how differences in task parameters, such as motivational incentives, affect overall task performance. Here, we provide a detailed methodological description of the setup and procedures for training mice efficiently on a two-choice lick left/lick right visual discrimination task. We characterize the effects of two distinct restriction regimens, i.e. food and water restriction, on animal wellbeing, activity patterns, task acquisition, and performance. While we observed reduced behavioral activity during the period of food and water restriction, the average animal discomfort scores remained in the 'sub-threshold' and 'mild' categories throughout the experiment, irrespective of the restriction regimen. We found that the type of restriction significantly influenced specific aspects of task acquisition and engagement, i.e. the number of sessions until the learning criterion was reached and the number of trials performed per session, but it did not affect maximum learning curve performance. These results indicate that the choice of restriction paradigm does not strongly affect animal wellbeing, but it can have a significant effect on how mice perform in a task.
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Affiliation(s)
- Pieter M. Goltstein
- Max Planck Institute of Neurobiology, Martinsried, Germany
- * E-mail: (PG); (MH)
| | - Sandra Reinert
- Max Planck Institute of Neurobiology, Martinsried, Germany
- Graduate School of Systemic Neurosciences, Martinsried, Germany
| | - Annet Glas
- Max Planck Institute of Neurobiology, Martinsried, Germany
- Graduate School of Systemic Neurosciences, Martinsried, Germany
| | | | - Mark Hübener
- Max Planck Institute of Neurobiology, Martinsried, Germany
- * E-mail: (PG); (MH)
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33
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Hansen KR, DeWalt GJ, Mohammed AI, Tseng HA, Abdulkerim ME, Bensussen S, Saligrama V, Nazer B, Eldred WD, Han X. Mild Blast Injury Produces Acute Changes in Basal Intracellular Calcium Levels and Activity Patterns in Mouse Hippocampal Neurons. J Neurotrauma 2018; 35:1523-1536. [PMID: 29343209 PMCID: PMC5998839 DOI: 10.1089/neu.2017.5029] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Mild traumatic brain injury (mTBI) represents a serious public health concern. Although much is understood about long-term changes in cell signaling and anatomical pathologies associated with mTBI, little is known about acute changes in neuronal function. Using large scale Ca2+ imaging in vivo, we characterized the intracellular Ca2+ dynamics in thousands of individual hippocampal neurons using a repetitive mild blast injury model in which blasts were directed onto the cranium of unanesthetized mice on two consecutive days. Immediately following each blast event, neurons exhibited two types of changes in Ca2+ dynamics at different time scales. One was a reduction in slow Ca2+ dynamics that corresponded to shifts in basal intracellular Ca2+ levels at a time scale of minutes, suggesting a disruption of biochemical signaling. The second was a reduction in the rates of fast transient Ca2+ fluctuations at the sub-second time scale, which are known to be closely linked to neural activity. Interestingly, the blast-induced changes in basal Ca2+ levels were independent of the changes in the rates of fast Ca2+ transients, suggesting that blasts had heterogeneous effects on different cell populations. Both types of changes recovered after ∼1 h. Together, our results demonstrate that mTBI induced acute, heterogeneous changes in neuronal function, altering intracellular Ca2+ dynamics across different time scales, which may contribute to the initiation of longer-term pathologies.
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Affiliation(s)
- Kyle R. Hansen
- Department of Biomedical Engineering, Boston University, Boston, Massachusetts
| | | | - Ali I. Mohammed
- Department of Biomedical Engineering, Boston University, Boston, Massachusetts
| | - Hua-an Tseng
- Department of Biomedical Engineering, Boston University, Boston, Massachusetts
| | - Moona E. Abdulkerim
- Department of Biomedical Engineering, Boston University, Boston, Massachusetts
| | - Seth Bensussen
- Department of Biomedical Engineering, Boston University, Boston, Massachusetts
| | - Venkatesh Saligrama
- Department of Electrical and Computer Engineering, Boston University, Boston, Massachusetts
| | - Bobak Nazer
- Department of Electrical and Computer Engineering, Boston University, Boston, Massachusetts
| | | | - Xue Han
- Department of Biomedical Engineering, Boston University, Boston, Massachusetts
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34
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Weiler S, Bauer J, Hübener M, Bonhoeffer T, Rose T, Scheuss V. High-yield in vitro recordings from neurons functionally characterized in vivo. Nat Protoc 2018; 13:1275-1293. [DOI: 10.1038/nprot.2018.026] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
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35
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Abe K, Yawo H. Optogenetic conditioning of paradigm and pattern discrimination in the rat somatosensory system. PLoS One 2017; 12:e0189439. [PMID: 29267341 PMCID: PMC5739416 DOI: 10.1371/journal.pone.0189439] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2017] [Accepted: 11/25/2017] [Indexed: 11/23/2022] Open
Abstract
The rodent whisker-barrel cortical system is a model for studying somatosensory discrimination at high spatiotemporal precision. Here, we applied optogenetics to produce somatosensory inputs in the whisker area using one of transgenic rat lines, W-TChR2V4, which expresses channelrhodopsin-2 (ChR2) in the mechanoreceptive nerve endings around whisker follicles. An awake W-TChR2V4 rat was head-fixed and irradiated by blue LED light on the whisker area with a paradigm conditioned with a reward. The Go task was designed so the rat is allowed to receive a reward, when it licked the nozzle within 5 s after photostimulation. The No-go task was designed so as the rat has to withhold licking for at least 5 s to obtain a reward after photostimulation. The Go-task conditioning was established within 1 hr of training with a reduction in the reaction time and increase of the success rate. To investigate the relationship between the spatiotemporal pattern of sensory inputs and the behavioral output, we designed a multi-optical fiber system that irradiates the whisker area at 9 spots in a 3×3 matrix. Although the Go-task conditioning was established using synchronous irradiation of 9 spots, the success rate was decreased with an increase of the reaction time for the asynchronous irradiation. After conditioning to the Go task, the rat responded to the blue LED flash irradiated on the barrel cortex, where many neurons also express ChR2, or photostimulation of the contralateral whisker area with a similar reaction time and success rate. Synchronous activation of the peripheral mechanoreceptive nerves is suggested to drive a neural circuit in the somatosensory cortex that efficiently couples with the decision. Our optogenetic system would enable the precise evaluation of the psychophysical values, such as the reaction time and success rate, to gain some insight into the brain mechanisms underlying conditioned behaviors.
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Affiliation(s)
- Kenta Abe
- Department of Development Biology and Neuroscience, Tohoku University Graduate School of Life Science, Sendai, Japan
| | - Hiromu Yawo
- Department of Development Biology and Neuroscience, Tohoku University Graduate School of Life Science, Sendai, Japan
- Center for Neuroscience, Tohoku University Graduate School of Medicine, Sendai, Japan
- * E-mail:
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36
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Silasi G, Boyd JD, Bolanos F, LeDue JM, Scott SH, Murphy TH. Individualized tracking of self-directed motor learning in group-housed mice performing a skilled lever positioning task in the home cage. J Neurophysiol 2017; 119:337-346. [PMID: 29070625 DOI: 10.1152/jn.00115.2017] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Skilled forelimb function in mice is traditionally studied through behavioral paradigms that require extensive training by investigators and are limited by the number of trials individual animals are able to perform within a supervised session. We developed a skilled lever positioning task that mice can perform within their home cage. The task requires mice to use their forelimb to precisely hold a lever mounted on a rotary encoder within a rewarded position to dispense a water reward. A Raspberry Pi microcomputer is used to record lever position during trials and to control task parameters, thus making this low-footprint apparatus ideal for use within animal housing facilities. Custom Python software automatically increments task difficulty by requiring a longer hold duration, or a more accurate hold position, to dispense a reward. The performance of individual animals within group-housed mice is tracked through radio-frequency identification implants, and data stored on the microcomputer may be accessed remotely through an active internet connection. Mice continuously engage in the task for over 2.5 mo and perform ~500 trials/24 h. Mice required ~15,000 trials to learn to hold the lever within a 10° range for 1.5 s and were able to further refine movement accuracy by limiting their error to a 5° range within each trial. These results demonstrate the feasibility of autonomously training group-housed mice on a forelimb motor task. This paradigm may be used in the future to assess functional recovery after injury or cortical reorganization induced by self-directed motor learning. NEW & NOTEWORTHY We developed a low-cost system for fully autonomous training of group-housed mice on a forelimb motor task. We demonstrate the feasibility of tracking both end-point, as well as kinematic performance of individual mice, with each performing thousands of trials over 2.5 mo. The task is run and controlled by a Raspberry Pi microcomputer, which allows for cages to be monitored remotely through an active internet connection.
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Affiliation(s)
- Gergely Silasi
- Department of Psychiatry, Kinsmen Laboratory of Neurological Research, Vancouver, British Columbia, Canada.,Djavad Mowafaghian Centre for Brain Health, University of British Columbia, Vancouver, British Columbia, Canada.,Department of Cellular and Molecular Medicine, University of Ottawa , Ottawa, Ontario , Canada
| | - Jamie D Boyd
- Department of Psychiatry, Kinsmen Laboratory of Neurological Research, Vancouver, British Columbia, Canada
| | - Federico Bolanos
- Department of Psychiatry, Kinsmen Laboratory of Neurological Research, Vancouver, British Columbia, Canada.,Djavad Mowafaghian Centre for Brain Health, University of British Columbia, Vancouver, British Columbia, Canada
| | - Jeff M LeDue
- Department of Psychiatry, Kinsmen Laboratory of Neurological Research, Vancouver, British Columbia, Canada.,Djavad Mowafaghian Centre for Brain Health, University of British Columbia, Vancouver, British Columbia, Canada
| | - Stephen H Scott
- Centre for Neuroscience Studies, Queen's University , Kingston, Ontario , Canada
| | - Timothy H Murphy
- Department of Psychiatry, Kinsmen Laboratory of Neurological Research, Vancouver, British Columbia, Canada.,Djavad Mowafaghian Centre for Brain Health, University of British Columbia, Vancouver, British Columbia, Canada
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37
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Wright PW, Brier LM, Bauer AQ, Baxter GA, Kraft AW, Reisman MD, Bice AR, Snyder AZ, Lee JM, Culver JP. Functional connectivity structure of cortical calcium dynamics in anesthetized and awake mice. PLoS One 2017; 12:e0185759. [PMID: 29049297 PMCID: PMC5648115 DOI: 10.1371/journal.pone.0185759] [Citation(s) in RCA: 69] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2016] [Accepted: 09/19/2017] [Indexed: 11/30/2022] Open
Abstract
The interplay between hemodynamic-based markers of cortical activity (e.g. fMRI and optical intrinsic signal imaging), which are an indirect and relatively slow report of neural activity, and underlying synaptic electrical and metabolic activity through neurovascular coupling is a topic of ongoing research and debate. As application of resting state functional connectivity measures is extended further into topics such as brain development, aging and disease, the importance of understanding the fundamental physiological basis for functional connectivity will grow. Here we extend functional connectivity analysis from hemodynamic- to calcium-based imaging. Transgenic mice (n = 7) expressing a fluorescent calcium indicator (GCaMP6) driven by the Thy1 promoter in glutamatergic neurons were imaged transcranially in both anesthetized (using ketamine/xylazine) and awake states. Sequential LED illumination (λ = 454, 523, 595, 640nm) enabled concurrent imaging of both GCaMP6 fluorescence emission (corrected for hemoglobin absorption) and hemodynamics. Functional connectivity network maps were constructed for infraslow (0.009–0.08Hz), intermediate (0.08–0.4Hz), and high (0.4–4.0Hz) frequency bands. At infraslow and intermediate frequencies, commonly used in BOLD fMRI and fcOIS studies of functional connectivity and implicated in neurovascular coupling mechanisms, GCaMP6 and HbO2 functional connectivity structures were in high agreement, both qualitatively and also quantitatively through a measure of spatial similarity. The spontaneous dynamics of both contrasts had the highest correlation when the GCaMP6 signal was delayed with a ~0.6–1.5s temporal offset. Within the higher-frequency delta band, sensitive to slow wave sleep oscillations in non-REM sleep and anesthesia, we evaluate the speed with which the connectivity analysis stabilized and found that the functional connectivity maps captured putative network structure within time window lengths as short as 30 seconds. Homotopic GCaMP6 functional connectivity maps at 0.4–4.0Hz in the anesthetized states show a striking correlated and anti-correlated structure along the anterior to posterior axis. This structure is potentially explained in part by observed propagation of delta-band activity from frontal somatomotor regions to visuoparietal areas. During awake imaging, this spatio-temporal quality is altered, and a more complex and detailed functional connectivity structure is observed. The combined calcium/hemoglobin imaging technique described here will enable the dissociation of changes in ionic and hemodynamic functional structure and neurovascular coupling and provide a framework for subsequent studies of neurological disease such as stroke.
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Affiliation(s)
- Patrick W. Wright
- Department of Biomedical Engineering, Washington University in St. Louis, St. Louis, Missouri, United States of America
- Department of Radiology, Washington University School of Medicine, St. Louis, Missouri, United States of America
| | - Lindsey M. Brier
- Department of Neuroscience, Washington University in St. Louis, St. Louis, Missouri, United States of America
| | - Adam Q. Bauer
- Department of Radiology, Washington University School of Medicine, St. Louis, Missouri, United States of America
| | - Grant A. Baxter
- Department of Radiology, Washington University School of Medicine, St. Louis, Missouri, United States of America
| | - Andrew W. Kraft
- Department of Neuroscience, Washington University in St. Louis, St. Louis, Missouri, United States of America
| | - Matthew D. Reisman
- Department of Radiology, Washington University School of Medicine, St. Louis, Missouri, United States of America
- Department of Physics, Washington University in St. Louis, St. Louis, Missouri, United States of America
| | - Annie R. Bice
- Department of Radiology, Washington University School of Medicine, St. Louis, Missouri, United States of America
| | - Abraham Z. Snyder
- Department of Radiology, Washington University School of Medicine, St. Louis, Missouri, United States of America
| | - Jin-Moo Lee
- Department of Biomedical Engineering, Washington University in St. Louis, St. Louis, Missouri, United States of America
- Department of Radiology, Washington University School of Medicine, St. Louis, Missouri, United States of America
- Department Neurology, Washington University School of Medicine, St. Louis, Missouri, United States of America
| | - Joseph P. Culver
- Department of Biomedical Engineering, Washington University in St. Louis, St. Louis, Missouri, United States of America
- Department of Radiology, Washington University School of Medicine, St. Louis, Missouri, United States of America
- Department of Neuroscience, Washington University in St. Louis, St. Louis, Missouri, United States of America
- * E-mail:
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38
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Kim DH, Kim J, Marques JC, Grama A, Hildebrand DGC, Gu W, Li JM, Robson DN. Pan-neuronal calcium imaging with cellular resolution in freely swimming zebrafish. Nat Methods 2017; 14:1107-1114. [DOI: 10.1038/nmeth.4429] [Citation(s) in RCA: 139] [Impact Index Per Article: 19.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2017] [Accepted: 07/29/2017] [Indexed: 12/15/2022]
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39
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Haupt D, Vanni MP, Bolanos F, Mitelut C, LeDue JM, Murphy TH. Mesoscale brain explorer, a flexible python-based image analysis and visualization tool. NEUROPHOTONICS 2017; 4:031210. [PMID: 28560240 PMCID: PMC5438099 DOI: 10.1117/1.nph.4.3.031210] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/16/2017] [Accepted: 04/24/2017] [Indexed: 06/07/2023]
Abstract
Imaging of mesoscale brain activity is used to map interactions between brain regions. This work has benefited from the pioneering studies of Grinvald et al., who employed optical methods to image brain function by exploiting the properties of intrinsic optical signals and small molecule voltage-sensitive dyes. Mesoscale interareal brain imaging techniques have been advanced by cell targeted and selective recombinant indicators of neuronal activity. Spontaneous resting state activity is often collected during mesoscale imaging to provide the basis for mapping of connectivity relationships using correlation. However, the information content of mesoscale datasets is vast and is only superficially presented in manuscripts given the need to constrain measurements to a fixed set of frequencies, regions of interest, and other parameters. We describe a new open source tool written in python, termed mesoscale brain explorer (MBE), which provides an interface to process and explore these large datasets. The platform supports automated image processing pipelines with the ability to assess multiple trials and combine data from different animals. The tool provides functions for temporal filtering, averaging, and visualization of functional connectivity relations using time-dependent correlation. Here, we describe the tool and show applications, where previously published datasets were reanalyzed using MBE.
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Affiliation(s)
- Dirk Haupt
- University of British Columbia, Kinsmen Laboratory of Neurological Research, Faculty of Medicine, Department of Psychiatry, Vancouver, Canada
- University of British Columbia, Djavad Mowafaghian Centre for Brain Health, Vancouver, Canada
| | - Matthieu P. Vanni
- University of British Columbia, Kinsmen Laboratory of Neurological Research, Faculty of Medicine, Department of Psychiatry, Vancouver, Canada
- University of British Columbia, Djavad Mowafaghian Centre for Brain Health, Vancouver, Canada
| | - Federico Bolanos
- University of British Columbia, Kinsmen Laboratory of Neurological Research, Faculty of Medicine, Department of Psychiatry, Vancouver, Canada
- University of British Columbia, Djavad Mowafaghian Centre for Brain Health, Vancouver, Canada
| | - Catalin Mitelut
- University of British Columbia, Kinsmen Laboratory of Neurological Research, Faculty of Medicine, Department of Psychiatry, Vancouver, Canada
- University of British Columbia, Djavad Mowafaghian Centre for Brain Health, Vancouver, Canada
| | - Jeffrey M. LeDue
- University of British Columbia, Kinsmen Laboratory of Neurological Research, Faculty of Medicine, Department of Psychiatry, Vancouver, Canada
- University of British Columbia, Djavad Mowafaghian Centre for Brain Health, Vancouver, Canada
| | - Tim H. Murphy
- University of British Columbia, Kinsmen Laboratory of Neurological Research, Faculty of Medicine, Department of Psychiatry, Vancouver, Canada
- University of British Columbia, Djavad Mowafaghian Centre for Brain Health, Vancouver, Canada
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40
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Fronto-parietal Cortical Circuits Encode Accumulated Evidence with a Diversity of Timescales. Neuron 2017; 95:385-398.e5. [PMID: 28669543 DOI: 10.1016/j.neuron.2017.06.013] [Citation(s) in RCA: 81] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2016] [Revised: 04/04/2017] [Accepted: 06/06/2017] [Indexed: 01/04/2023]
Abstract
Decision-making in dynamic environments often involves accumulation of evidence, in which new information is used to update beliefs and select future actions. Using in vivo cellular resolution imaging in voluntarily head-restrained rats, we examined the responses of neurons in frontal and parietal cortices during a pulse-based accumulation of evidence task. Neurons exhibited activity that predicted the animal's upcoming choice, previous choice, and graded responses that reflected the strength of the accumulated evidence. The pulsatile nature of the stimuli enabled characterization of the responses of neurons to a single quantum (pulse) of evidence. Across the population, individual neurons displayed extensive heterogeneity in the dynamics of responses to pulses. The diversity of responses was sufficiently rich to form a temporal basis for accumulated evidence estimated from a latent variable model. These results suggest that heterogeneous, often transient sensory responses distributed across the fronto-parietal cortex may support working memory on behavioral timescales. VIDEO ABSTRACT.
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Noorshams O, Boyd JD, Murphy TH. Automating mouse weighing in group homecages with Raspberry Pi micro-computers. J Neurosci Methods 2017; 285:1-5. [PMID: 28476590 DOI: 10.1016/j.jneumeth.2017.05.002] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2017] [Revised: 04/29/2017] [Accepted: 05/01/2017] [Indexed: 11/17/2022]
Abstract
BACKGROUND Operant training systems make use of water or food restriction and make it necessary to weigh animals to ensure compliance with experimental endpoints. In other applications periodic weighing is necessary to assess drug side-effects, or as an endpoint in feeding experiments. Periodic weighing while essential can disrupt animal circadian rhythms and social structure. NEW METHOD Automatic weighing system within paired mouse homecages. Up to 10 mice freely move between two cages (28×18×9cm) which were connected by a weighing chamber mounted on a load cell. Each mouse was identified using an RFID tag placed under the skin of the neck. A single-board computer (Raspberry Pi; RPi) controls the task, logging RFID tag, load cell weights, and time stamps from each RFID detection until the animal leaves the chamber. Collected data were statistically analyzed to estimate mouse weights. We anticipate integration with tasks where automated imaging or behaviour is assessed in homecages. RESULTS Mice frequently move between the two cages, an average of 42+-16 times/day/mouse at which time we obtained weights. We report accurate determination of mouse weight and long term monitoring over 53days. Comparison with existing methods Although commercial systems are available for automatically weighing rodents, they only work with single animals, or are not open source nor cost effective for specific custom application. CONCLUSIONS This automated system permits automated weighing of mice ∼40 times per day. The system employs inexpensive hardware and open-source Python code.
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Affiliation(s)
- Omid Noorshams
- Department of Psychiatry, Kinsmen Laboratory of Neurological Research, Canada; Djavad Mowafaghian Centre for Brain Health, University of British Columbia, Vancouver, British Columbia, V6T 1Z3, Canada
| | - Jamie D Boyd
- Department of Psychiatry, Kinsmen Laboratory of Neurological Research, Canada; Djavad Mowafaghian Centre for Brain Health, University of British Columbia, Vancouver, British Columbia, V6T 1Z3, Canada
| | - Timothy H Murphy
- Department of Psychiatry, Kinsmen Laboratory of Neurological Research, Canada; Djavad Mowafaghian Centre for Brain Health, University of British Columbia, Vancouver, British Columbia, V6T 1Z3, Canada.
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Hoshiba Y, Wada T, Hayashi-Takagi A. Synaptic Ensemble Underlying the Selection and Consolidation of Neuronal Circuits during Learning. Front Neural Circuits 2017; 11:12. [PMID: 28303092 PMCID: PMC5332426 DOI: 10.3389/fncir.2017.00012] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2016] [Accepted: 02/20/2017] [Indexed: 12/20/2022] Open
Abstract
Memories are crucial to the cognitive essence of who we are as human beings. Accumulating evidence has suggested that memories are stored as a subset of neurons that probably fire together in the same ensemble. Such formation of cell ensembles must meet contradictory requirements of being plastic and responsive during learning, but also stable in order to maintain the memory. Although synaptic potentiation is presumed to be the cellular substrate for this process, the link between the two remains correlational. With the application of the latest optogenetic tools, it has been possible to collect direct evidence of the contributions of synaptic potentiation in the formation and consolidation of cell ensemble in a learning task specific manner. In this review, we summarize the current view of the causative role of synaptic plasticity as the cellular mechanism underlying the encoding of memory and recalling of learned memories. In particular, we will be focusing on the latest optoprobe developed for the visualization of such “synaptic ensembles.” We further discuss how a new synaptic ensemble could contribute to the formation of cell ensembles during learning and memory. With the development and application of novel research tools in the future, studies on synaptic ensembles will pioneer new discoveries, eventually leading to a comprehensive understanding of how the brain works.
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Affiliation(s)
- Yoshio Hoshiba
- Laboratory of Medical Neuroscience, Institute for Molecular and Cellular Regulation, Gunma University Maebashi, Japan
| | - Takeyoshi Wada
- Laboratory of Medical Neuroscience, Institute for Molecular and Cellular Regulation, Gunma University Maebashi, Japan
| | - Akiko Hayashi-Takagi
- Laboratory of Medical Neuroscience, Institute for Molecular and Cellular Regulation, Gunma UniversityMaebashi, Japan; PRESTO, Japan Science and Technology AgencyKawaguchi, Japan
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Cao R, Li J, Ning B, Sun N, Wang T, Zuo Z, Hu S. Functional and oxygen-metabolic photoacoustic microscopy of the awake mouse brain. Neuroimage 2017; 150:77-87. [PMID: 28111187 DOI: 10.1016/j.neuroimage.2017.01.049] [Citation(s) in RCA: 88] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2016] [Revised: 12/10/2016] [Accepted: 01/19/2017] [Indexed: 01/22/2023] Open
Abstract
A long-standing challenge in optical neuroimaging has been the assessment of hemodynamics and oxygen metabolism in the awake rodent brain at the microscopic level. Here, we report first-of-a-kind head-restrained photoacoustic microscopy (PAM), which enables simultaneous imaging of the cerebrovascular anatomy, total concentration and oxygen saturation of hemoglobin, and blood flow in awake mice. Combining these hemodynamic measurements allows us to derive two key metabolic parameters-oxygen extraction fraction (OEF) and the cerebral metabolic rate of oxygen (CMRO2). This enabling technology offers the first opportunity to comprehensively and quantitatively characterize the hemodynamic and oxygen-metabolic responses of the mouse brain to isoflurane, a general anesthetic widely used in preclinical research and clinical practice. Side-by-side comparison of the awake and anesthetized brains reveals that isoflurane induces diameter-dependent arterial dilation, elevated blood flow, and reduced OEF in a dose-dependent manner. As a result of the combined effects, CMRO2 is significantly reduced in the anesthetized brain under both normoxia and hypoxia, which suggests a mechanism for anesthetic neuroprotection. The head-restrained functional and metabolic PAM opens a new avenue for basic and translational research on neurovascular coupling without the strong influence of anesthesia and on the neuroprotective effects of various interventions, including but not limited to volatile anesthetics, against cerebral hypoxia and ischemia.
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Affiliation(s)
- Rui Cao
- Department of Biomedical Engineering, University of Virginia, VA 22908, USA
| | - Jun Li
- Department of Anesthesiology, University of Virginia, VA 22908, USA
| | - Bo Ning
- Department of Biomedical Engineering, University of Virginia, VA 22908, USA
| | - Naidi Sun
- Department of Biomedical Engineering, University of Virginia, VA 22908, USA
| | - Tianxiong Wang
- Department of Biomedical Engineering, University of Virginia, VA 22908, USA
| | - Zhiyi Zuo
- Department of Anesthesiology, University of Virginia, VA 22908, USA.
| | - Song Hu
- Department of Biomedical Engineering, University of Virginia, VA 22908, USA.
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Gao YR, Ma Y, Zhang Q, Winder AT, Liang Z, Antinori L, Drew PJ, Zhang N. Time to wake up: Studying neurovascular coupling and brain-wide circuit function in the un-anesthetized animal. Neuroimage 2016; 153:382-398. [PMID: 27908788 PMCID: PMC5526447 DOI: 10.1016/j.neuroimage.2016.11.069] [Citation(s) in RCA: 124] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2016] [Revised: 11/18/2016] [Accepted: 11/27/2016] [Indexed: 01/08/2023] Open
Abstract
Functional magnetic resonance imaging (fMRI) has allowed the noninvasive study of task-based and resting-state brain dynamics in humans by inferring neural activity from blood-oxygenation-level dependent (BOLD) signal changes. An accurate interpretation of the hemodynamic changes that underlie fMRI signals depends on the understanding of the quantitative relationship between changes in neural activity and changes in cerebral blood flow, oxygenation and volume. While there has been extensive study of neurovascular coupling in anesthetized animal models, anesthesia causes large disruptions of brain metabolism, neural responsiveness and cardiovascular function. Here, we review work showing that neurovascular coupling and brain circuit function in the awake animal are profoundly different from those in the anesthetized state. We argue that the time is right to study neurovascular coupling and brain circuit function in the awake animal to bridge the physiological mechanisms that underlie animal and human neuroimaging signals, and to interpret them in light of underlying neural mechanisms. Lastly, we discuss recent experimental innovations that have enabled the study of neurovascular coupling and brain-wide circuit function in un-anesthetized and behaving animal models.
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Affiliation(s)
- Yu-Rong Gao
- Neuroscience Graduate Program, Pennsylvania State University, University Park, PA 16802, Unidted States; Department of Engineering Science and Mechanics, Pennsylvania State University, University Park, PA 16802, Unidted States
| | - Yuncong Ma
- Department of Biomedical Engineering, Pennsylvania State University, University Park, PA 16802, Unidted States
| | - Qingguang Zhang
- Department of Engineering Science and Mechanics, Pennsylvania State University, University Park, PA 16802, Unidted States
| | - Aaron T Winder
- Department of Engineering Science and Mechanics, Pennsylvania State University, University Park, PA 16802, Unidted States
| | - Zhifeng Liang
- Department of Biomedical Engineering, Pennsylvania State University, University Park, PA 16802, Unidted States
| | - Lilith Antinori
- Department of Biomedical Engineering, Pennsylvania State University, University Park, PA 16802, Unidted States
| | - Patrick J Drew
- Neuroscience Graduate Program, Pennsylvania State University, University Park, PA 16802, Unidted States; Department of Engineering Science and Mechanics, Pennsylvania State University, University Park, PA 16802, Unidted States; Department of Neurosurgery, Pennsylvania State University, University Park, PA 16802, Unidted States; Department of Biomedical Engineering, Pennsylvania State University, University Park, PA 16802, Unidted States.
| | - Nanyin Zhang
- Neuroscience Graduate Program, Pennsylvania State University, University Park, PA 16802, Unidted States; Department of Biomedical Engineering, Pennsylvania State University, University Park, PA 16802, Unidted States.
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Watakabe A, Sadakane O, Hata K, Ohtsuka M, Takaji M, Yamamori T. Application of viral vectors to the study of neural connectivities and neural circuits in the marmoset brain. Dev Neurobiol 2016; 77:354-372. [PMID: 27706918 PMCID: PMC5324647 DOI: 10.1002/dneu.22459] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2016] [Revised: 09/18/2016] [Accepted: 09/20/2016] [Indexed: 01/20/2023]
Abstract
It is important to study the neural connectivities and functions in primates. For this purpose, it is critical to be able to transfer genes to certain neurons in the primate brain so that we can image the neuronal signals and analyze the function of the transferred gene. Toward this end, our team has been developing gene transfer systems using viral vectors. In this review, we summarize our current achievements as follows. 1) We compared the features of gene transfer using five different AAV serotypes in combination with three different promoters, namely, CMV, mouse CaMKII (CaMKII), and human synapsin 1 (hSyn1), in the marmoset cortex with those in the mouse and macaque cortices. 2) We used target‐specific double‐infection techniques in combination with TET‐ON and TET‐OFF using lentiviral retrograde vectors for enhanced visualization of neural connections. 3) We used an AAV‐mediated gene transfer method to study the transcriptional control for amplifying fluorescent signals using the TET/TRE system in the primate neocortex. We also established systems for shRNA mediated gene targeting in a neocortical region where a gene is significantly expressed and for expressing the gene using the CMV promoter for an unexpressed neocortical area in the primate cortex using AAV vectors to understand the regulation of downstream genes. Our findings have demonstrated the feasibility of using viral vector mediated gene transfer systems for the study of primate cortical circuits using the marmoset as an animal model. © 2016 Wiley Periodicals, Inc. Develop Neurobiol 77: 354–372, 2017
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Affiliation(s)
- Akiya Watakabe
- Laboratory for Molecular Analysis of Higher Brain Function, Brain Science Institute, RIKEN, 2-1 Hirosawa, Wako, Saitama, 351-0198, Japan
| | - Osamu Sadakane
- Laboratory for Molecular Analysis of Higher Brain Function, Brain Science Institute, RIKEN, 2-1 Hirosawa, Wako, Saitama, 351-0198, Japan
| | - Katsusuke Hata
- Laboratory for Molecular Analysis of Higher Brain Function, Brain Science Institute, RIKEN, 2-1 Hirosawa, Wako, Saitama, 351-0198, Japan
| | - Masanari Ohtsuka
- Laboratory for Molecular Analysis of Higher Brain Function, Brain Science Institute, RIKEN, 2-1 Hirosawa, Wako, Saitama, 351-0198, Japan
| | - Masafumi Takaji
- Laboratory for Molecular Analysis of Higher Brain Function, Brain Science Institute, RIKEN, 2-1 Hirosawa, Wako, Saitama, 351-0198, Japan
| | - Tetsuo Yamamori
- Laboratory for Molecular Analysis of Higher Brain Function, Brain Science Institute, RIKEN, 2-1 Hirosawa, Wako, Saitama, 351-0198, Japan
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Sigal I, Koletar MM, Ringuette D, Gad R, Jeffrey M, Carlen PL, Stefanovic B, Levi O. Imaging brain activity during seizures in freely behaving rats using a miniature multi-modal imaging system. BIOMEDICAL OPTICS EXPRESS 2016; 7:3596-3609. [PMID: 27699123 PMCID: PMC5030035 DOI: 10.1364/boe.7.003596] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/17/2016] [Revised: 08/11/2016] [Accepted: 08/11/2016] [Indexed: 05/20/2023]
Abstract
We report on a miniature label-free imaging system for monitoring brain blood flow and blood oxygenation changes in awake, freely behaving rats. The device, weighing 15 grams, enables imaging in a ∼ 2 × 2 mm field of view with 4.4 μm lateral resolution and 1 - 8 Hz temporal sampling rate. The imaging is performed through a chronically-implanted cranial window that remains optically clear between 2 to > 6 weeks after the craniotomy. This imaging method is well suited for longitudinal studies of chronic models of brain diseases and disorders. In this work, it is applied to monitoring neurovascular coupling during drug-induced absence-like seizures 6 weeks following the craniotomy.
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Affiliation(s)
- Iliya Sigal
- Institute of Biomaterials and Biomedical Engineering, University of Toronto, 164 College Street, Toronto, ON M5S 3G9,
Canada
- The Edward S. Rogers Sr. Department of Electrical and Computer Engineering, 10 King’s College Road, Toronto, ON M5S 3G4,
Canada
| | - Margaret M. Koletar
- Sunnybrook Research Institute, 2075 Bayview Avenue, Toronto, ON M4N 3M5,
Canada
| | - Dene Ringuette
- Institute of Biomaterials and Biomedical Engineering, University of Toronto, 164 College Street, Toronto, ON M5S 3G9,
Canada
| | - Raanan Gad
- Institute of Biomaterials and Biomedical Engineering, University of Toronto, 164 College Street, Toronto, ON M5S 3G9,
Canada
- The Edward S. Rogers Sr. Department of Electrical and Computer Engineering, 10 King’s College Road, Toronto, ON M5S 3G4,
Canada
| | - Melanie Jeffrey
- Krembil Research Institute, 60 Leonard Avenue, Toronto, ON M5T 2S1,
Canada
| | - Peter L. Carlen
- Institute of Biomaterials and Biomedical Engineering, University of Toronto, 164 College Street, Toronto, ON M5S 3G9,
Canada
- Krembil Research Institute, 60 Leonard Avenue, Toronto, ON M5T 2S1,
Canada
| | - Bojana Stefanovic
- Sunnybrook Research Institute, 2075 Bayview Avenue, Toronto, ON M4N 3M5,
Canada
- Department of Medical Biophysics, University of Toronto, 2075 Bayview Avenue, Toronto, ON M4N 3M5,
Canada
| | - Ofer Levi
- Institute of Biomaterials and Biomedical Engineering, University of Toronto, 164 College Street, Toronto, ON M5S 3G9,
Canada
- The Edward S. Rogers Sr. Department of Electrical and Computer Engineering, 10 King’s College Road, Toronto, ON M5S 3G4,
Canada
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Murphy TH, Boyd JD, Bolaños F, Vanni MP, Silasi G, Haupt D, LeDue JM. High-throughput automated home-cage mesoscopic functional imaging of mouse cortex. Nat Commun 2016; 7:11611. [PMID: 27291514 PMCID: PMC4909937 DOI: 10.1038/ncomms11611] [Citation(s) in RCA: 57] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2015] [Accepted: 04/12/2016] [Indexed: 12/14/2022] Open
Abstract
Mouse head-fixed behaviour coupled with functional imaging has become a powerful technique in rodent systems neuroscience. However, training mice can be time consuming and is potentially stressful for animals. Here we report a fully automated, open source, self-initiated head-fixation system for mesoscopic functional imaging in mice. The system supports five mice at a time and requires minimal investigator intervention. Using genetically encoded calcium indicator transgenic mice, we longitudinally monitor cortical functional connectivity up to 24 h per day in >7,000 self-initiated and unsupervised imaging sessions up to 90 days. The procedure provides robust assessment of functional cortical maps on the basis of both spontaneous activity and brief sensory stimuli such as light flashes. The approach is scalable to a number of remotely controlled cages that can be assessed within the controlled conditions of dedicated animal facilities. We anticipate that home-cage brain imaging will permit flexible and chronic assessment of mesoscale cortical function. Functional imaging in awake head-fixed mice is a widely used technique to study neural responses. Here the authors report on an open source, fully automated unsupervised system for training mice to self initiate head fixation to enable stable mesoscopic functional imaging of cortical functional connectivity.
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Affiliation(s)
- Timothy H Murphy
- Department of Psychiatry, Kinsmen Laboratory of Neurological Research, University of British Columbia, Vancouver, British Columbia, Canada V6T 1Z3.,Djavad Mowafaghian Centre for Brain Health, University of British Columbia, Vancouver, British Columbia, Canada V6T 1Z3
| | - Jamie D Boyd
- Department of Psychiatry, Kinsmen Laboratory of Neurological Research, University of British Columbia, Vancouver, British Columbia, Canada V6T 1Z3.,Djavad Mowafaghian Centre for Brain Health, University of British Columbia, Vancouver, British Columbia, Canada V6T 1Z3
| | - Federico Bolaños
- Department of Psychiatry, Kinsmen Laboratory of Neurological Research, University of British Columbia, Vancouver, British Columbia, Canada V6T 1Z3.,Djavad Mowafaghian Centre for Brain Health, University of British Columbia, Vancouver, British Columbia, Canada V6T 1Z3
| | - Matthieu P Vanni
- Department of Psychiatry, Kinsmen Laboratory of Neurological Research, University of British Columbia, Vancouver, British Columbia, Canada V6T 1Z3.,Djavad Mowafaghian Centre for Brain Health, University of British Columbia, Vancouver, British Columbia, Canada V6T 1Z3
| | - Gergely Silasi
- Department of Psychiatry, Kinsmen Laboratory of Neurological Research, University of British Columbia, Vancouver, British Columbia, Canada V6T 1Z3.,Djavad Mowafaghian Centre for Brain Health, University of British Columbia, Vancouver, British Columbia, Canada V6T 1Z3
| | - Dirk Haupt
- Department of Psychiatry, Kinsmen Laboratory of Neurological Research, University of British Columbia, Vancouver, British Columbia, Canada V6T 1Z3.,Djavad Mowafaghian Centre for Brain Health, University of British Columbia, Vancouver, British Columbia, Canada V6T 1Z3
| | - Jeff M LeDue
- Department of Psychiatry, Kinsmen Laboratory of Neurological Research, University of British Columbia, Vancouver, British Columbia, Canada V6T 1Z3.,Djavad Mowafaghian Centre for Brain Health, University of British Columbia, Vancouver, British Columbia, Canada V6T 1Z3
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Brody CD, Hanks TD. Neural underpinnings of the evidence accumulator. Curr Opin Neurobiol 2016; 37:149-157. [PMID: 26878969 PMCID: PMC5777584 DOI: 10.1016/j.conb.2016.01.003] [Citation(s) in RCA: 88] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2015] [Accepted: 01/05/2016] [Indexed: 01/11/2023]
Abstract
Gradual accumulation of evidence favoring one or another choice is considered a core component of many different types of decisions, and has been the subject of many neurophysiological studies in non-human primates. But its neural circuit mechanisms remain mysterious. Investigating it in rodents has recently become possible, facilitating perturbation experiments to delineate the relevant causal circuit, as well as the application of other tools more readily available in rodents. In addition, advances in stimulus design and analysis have aided studying the relevant neural encoding. In complement to ongoing non-human primate studies, these newly available model systems and tools place the field at an exciting time that suggests that the dynamical circuit mechanisms underlying accumulation of evidence could soon be revealed.
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Affiliation(s)
- Carlos D Brody
- Howard Hughes Medical Institute, USA; Princeton Neuroscience Institute and Department of Molecular Biology, Princeton University, Princeton, NJ 08540, USA.
| | - Timothy D Hanks
- Center for Neuroscience, University of California Davis, Davis, CA 95618, USA; Department of Neurology, University of California Davis, Sacramento, CA 95817, USA
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Scott BB, Constantinople CM, Erlich JC, Tank DW, Brody CD. Sources of noise during accumulation of evidence in unrestrained and voluntarily head-restrained rats. eLife 2015; 4:e11308. [PMID: 26673896 PMCID: PMC4749559 DOI: 10.7554/elife.11308] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2015] [Accepted: 12/15/2015] [Indexed: 11/13/2022] Open
Abstract
Decision-making behavior is often characterized by substantial variability, but its source remains unclear. We developed a visual accumulation of evidence task designed to quantify sources of noise and to be performed during voluntary head restraint, enabling cellular resolution imaging in future studies. Rats accumulated discrete numbers of flashes presented to the left and right visual hemifields and indicated the side that had the greater number of flashes. Using a signal-detection theory-based model, we found that the standard deviation in their internal estimate of flash number scaled linearly with the number of flashes. This indicates a major source of noise that, surprisingly, is not consistent with the widely used 'drift-diffusion modeling' (DDM) approach but is instead closely related to proposed models of numerical cognition and counting. We speculate that this form of noise could be important in accumulation of evidence tasks generally. DOI:http://dx.doi.org/10.7554/eLife.11308.001 Perceptual decision-making, i.e. making choices based on observed evidence, is rarely perfect. Humans and other animals tend to respond correctly on some trials and incorrectly on others. For over a century, this variability has been used to study the basis of decision-making. Most behavioral models assume that random fluctuations or 'noise' in the decision-making process is the primary source of variability and errors. However, the nature of this noise is unclear and the subject of intense scrutiny. To investigate the sources of the behavioral variability during decision-making, Scott, Constantinople et al. trained rats to perform a visual 'accumulation of evidence' task. The animals counted flashes of light that appeared on either their left or their right. Up to 15 flashes occurred on each side, in a random order, and the rats then received a reward if they selected the side that the greatest number of flashes had occurred on. The rats chose correctly on many occasions but not on every single one. Using a computer-controlled rat training facility or 'rat academy', Scott, Constantinople et al. collected hundreds of thousands of behavioral trials from over a dozen rats. This large dataset provided the statistical power necessary to test the assumptions of leading models of behavioral variability during decision-making, and revealed that noise grew more rapidly with the number of flashes than previously predicted. This finding explained patterns of behavior that previous models struggled with, most notably the fact that individuals make errors even on the easiest trials. The analysis also revealed that animals maintain two separate running totals – one of stimuli on the left and another of stimuli on the right – rather than a single tally of the difference between the two. Scott, Constantinople et al. further demonstrated that rats could be trained to perform this task using a new system that enables functional brain imaging. The next step is to repeat these experiments while simultaneously recording brain activity to study the neural circuits that underlie decision-making and its variability. DOI:http://dx.doi.org/10.7554/eLife.11308.002
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Affiliation(s)
- Benjamin B Scott
- Princeton Neuroscience Institute, Princeton University, Princeton, United States.,Department of Molecular Biology, Princeton University, Princeton, United States
| | - Christine M Constantinople
- Princeton Neuroscience Institute, Princeton University, Princeton, United States.,Department of Molecular Biology, Princeton University, Princeton, United States
| | - Jeffrey C Erlich
- NYU-ECNU Institute of Brain and Cognitive Science, New York University Shanghai, Shanghai, China
| | - David W Tank
- Princeton Neuroscience Institute, Princeton University, Princeton, United States.,Department of Molecular Biology, Princeton University, Princeton, United States.,Bezos Center for Neural Circuit Dynamics, Princeton University, Princeton, United States
| | - Carlos D Brody
- Princeton Neuroscience Institute, Princeton University, Princeton, United States.,Department of Molecular Biology, Princeton University, Princeton, United States.,Howard Hughes Medical Institute, Princeton University, Princeton, United States
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50
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Neurons in the most superficial lamina of the mouse superior colliculus are highly selective for stimulus direction. J Neurosci 2015; 35:7992-8003. [PMID: 25995482 DOI: 10.1523/jneurosci.0173-15.2015] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
The superior colliculus (SC) is a layered midbrain structure important for multimodal integration and sensorimotor transformation. Its superficial layers are purely visual and receive depth-specific projections from distinct subtypes of retinal ganglion cells. Here we use two-photon calcium imaging to characterize the response properties of neurons in the most superficial lamina of the mouse SC, an undersampled population with electrophysiology. We find that these neurons have compact receptive fields with primarily overlapping ON and OFF subregions and are highly direction selective. The high selectivity is observed in both excitatory and inhibitory neurons. These neurons do not cluster according to their direction preference and lack orientation selectivity. In addition, we perform single-unit recordings and show that direction selectivity declines with depth in the SC. Together, our experiments reveal for the first time a highly specialized lamina in the most superficial SC for movement direction, a finding that has important implications for understanding signal transformation in the early visual system.
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