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Ma J, Majmudar A, Tian B. Bridging the Gap-Thermofluidic Designs for Precision Bioelectronics. Adv Healthc Mater 2024; 13:e2302431. [PMID: 37975642 DOI: 10.1002/adhm.202302431] [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: 07/28/2023] [Revised: 10/22/2023] [Indexed: 11/19/2023]
Abstract
Bioelectronics, the merging of biology and electronics, can monitor and modulate biological behaviors across length and time scales with unprecedented capability. Current bioelectronics research largely focuses on devices' mechanical properties and electronic designs. However, the thermofluidic control is often overlooked, which is noteworthy given the discipline's importance in almost all bioelectronics processes. It is believed that integrating thermofluidic designs into bioelectronics is essential to align device precision with the complexity of biofluids and biological structures. This perspective serves as a mini roadmap for researchers in both fields to introduce key principles, applications, and challenges in both bioelectronics and thermofluids domains. Important interdisciplinary opportunities for the development of future healthcare devices and precise bioelectronics will also be discussed.
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Affiliation(s)
- Jingcheng Ma
- The James Franck Institute, University of Chicago, Chicago, IL, 60637, USA
| | - Aman Majmudar
- The College, University of Chicago, Chicago, IL, 60637, USA
| | - Bozhi Tian
- The James Franck Institute, University of Chicago, Chicago, IL, 60637, USA
- Department of Chemistry, University of Chicago, Chicago, IL, 60637, USA
- The Institute for Biophysical Dynamics, University of Chicago, Chicago, IL, 60637, USA
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2
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Karashchuk L, Li JS(L, Chou GM, Walling-Bell S, Brunton SL, Tuthill JC, Brunton BW. Sensorimotor delays constrain robust locomotion in a 3D kinematic model of fly walking. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.04.18.589965. [PMID: 38712226 PMCID: PMC11071299 DOI: 10.1101/2024.04.18.589965] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2024]
Abstract
Walking animals must maintain stability in the presence of external perturbations, despite significant temporal delays in neural signaling and muscle actuation. Here, we develop a 3D kinematic model with a layered control architecture to investigate how sensorimotor delays constrain robustness of walking behavior in the fruit fly, Drosophila. Motivated by the anatomical architecture of insect locomotor control circuits, our model consists of three component layers: a neural network that generates realistic 3D joint kinematics for each leg, an optimal controller that executes the joint kinematics while accounting for delays, and an inter-leg coordinator. The model generates realistic simulated walking that matches real fly walking kinematics and sustains walking even when subjected to unexpected perturbations, generalizing beyond its training data. However, we found that the model's robustness to perturbations deteriorates when sensorimotor delay parameters exceed the physiological range. These results suggest that fly sensorimotor control circuits operate close to the temporal limit at which they can detect and respond to external perturbations. More broadly, we show how a modular, layered model architecture can be used to investigate physiological constraints on animal behavior.
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Affiliation(s)
- Lili Karashchuk
- Neuroscience Graduate Program, University of Washington, Seattle
| | - Jing Shuang (Lisa) Li
- Dept of Electrical Engineering and Computer Science, University of Michigan, Ann Arbor
| | - Grant M. Chou
- Dept of Physiology & Biophysics, University of Washington, Seattle
| | | | | | - John C. Tuthill
- Dept of Physiology & Biophysics, University of Washington, Seattle
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3
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Banerjee A, Chen F, Druckmann S, Long MA. Temporal scaling of motor cortical dynamics reveals hierarchical control of vocal production. Nat Neurosci 2024; 27:527-535. [PMID: 38291282 DOI: 10.1038/s41593-023-01556-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2023] [Accepted: 12/13/2023] [Indexed: 02/01/2024]
Abstract
Neocortical activity is thought to mediate voluntary control over vocal production, but the underlying neural mechanisms remain unclear. In a highly vocal rodent, the male Alston's singing mouse, we investigate neural dynamics in the orofacial motor cortex (OMC), a structure critical for vocal behavior. We first describe neural activity that is modulated by component notes (~100 ms), probably representing sensory feedback. At longer timescales, however, OMC neurons exhibit diverse and often persistent premotor firing patterns that stretch or compress with song duration (~10 s). Using computational modeling, we demonstrate that such temporal scaling, acting through downstream motor production circuits, can enable vocal flexibility. These results provide a framework for studying hierarchical control circuits, a common design principle across many natural and artificial systems.
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Affiliation(s)
- Arkarup Banerjee
- NYU Neuroscience Institute, New York University Langone Health, New York, NY, USA.
- Department of Otolaryngology, New York University Langone Health, New York, NY, USA.
- Center for Neural Science, New York University, New York, NY, USA.
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY, USA.
| | - Feng Chen
- Department of Applied Physics, Stanford University, Stanford, CA, USA
| | - Shaul Druckmann
- Department of Neurobiology, Stanford University, Stanford, CA, USA
| | - Michael A Long
- NYU Neuroscience Institute, New York University Langone Health, New York, NY, USA.
- Department of Otolaryngology, New York University Langone Health, New York, NY, USA.
- Center for Neural Science, New York University, New York, NY, USA.
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4
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Lindsay GW. Grounding neuroscience in behavioral changes using artificial neural networks. Curr Opin Neurobiol 2024; 84:102816. [PMID: 38052111 DOI: 10.1016/j.conb.2023.102816] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2023] [Revised: 09/15/2023] [Accepted: 11/05/2023] [Indexed: 12/07/2023]
Abstract
Connecting neural activity to function is a common aim in neuroscience. How to define and conceptualize function, however, can vary. Here I focus on grounding this goal in the specific question of how a given change in behavior is produced by a change in neural circuits or activity. Artificial neural network models offer a particularly fruitful format for tackling such questions because they use neural mechanisms to perform complex transformations and produce appropriate behavior. Therefore, they can be a means of causally testing the extent to which a neural change can be responsible for an experimentally observed behavioral change. Furthermore, because the field of interpretability in artificial intelligence has similar aims, neuroscientists can look to interpretability methods for new ways of identifying neural features that drive performance and behaviors.
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Affiliation(s)
- Grace W Lindsay
- Department of Psychology and Center for Data Science, New York University, USA.
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5
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Davoudi N, Estrada H, Özbek A, Shoham S, Razansky D. Model-based correction of rapid thermal confounds in fluorescence neuroimaging of targeted perturbation. NEUROPHOTONICS 2024; 11:014413. [PMID: 38371339 PMCID: PMC10871046 DOI: 10.1117/1.nph.11.1.014413] [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: 05/07/2023] [Revised: 12/01/2023] [Accepted: 12/01/2023] [Indexed: 02/20/2024]
Abstract
Significance An array of techniques for targeted neuromodulation is emerging, with high potential in brain research and therapy. Calcium imaging or other forms of functional fluorescence imaging are central solutions for monitoring cortical neural responses to targeted neuromodulation, but often are confounded by thermal effects that are inter-mixed with neural responses. Aim Here, we develop and demonstrate a method for effectively suppressing fluorescent thermal transients from calcium responses. Approach We use high precision phased-array 3 MHz focused ultrasound delivery integrated with fiberscope-based widefield fluorescence to monitor cortex-wide calcium changes. Our approach for detecting the neural activation first takes advantage of the high inter-hemispheric correlation of resting state Ca 2 + dynamics and then removes the ultrasound-induced thermal effect by subtracting its simulated spatio-temporal signature from the processed profile. Results The focused 350 μ m -sized ultrasound stimulus triggered rapid localized activation events dominated by transient thermal responses produced by ultrasound. By employing bioheat equation to model the ultrasound heat deposition, we can recover putative neural responses to ultrasound. Conclusions The developed method for canceling transient thermal fluorescence quenching could also find applications with optical stimulation techniques to monitor thermal effects and disentangle them from neural responses. This approach may help deepen our understanding of the mechanisms and macroscopic effects of ultrasound neuromodulation, further paving the way for tailoring the stimulation regimes toward specific applications.
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Affiliation(s)
- Neda Davoudi
- University of Zurich, Institute for Biomedical Engineering and Institute of Pharmacology and Toxicology, Faculty of Medicine, Zurich, Switzerland
- ETH Zurich, Institute for Biomedical Engineering, Department of Information Technology and Electrical Engineering, Zurich, Switzerland
- ETH AI Center, Zurich, Switzerland
| | - Hector Estrada
- University of Zurich, Institute for Biomedical Engineering and Institute of Pharmacology and Toxicology, Faculty of Medicine, Zurich, Switzerland
- ETH Zurich, Institute for Biomedical Engineering, Department of Information Technology and Electrical Engineering, Zurich, Switzerland
| | - Ali Özbek
- University of Zurich, Institute for Biomedical Engineering and Institute of Pharmacology and Toxicology, Faculty of Medicine, Zurich, Switzerland
- ETH Zurich, Institute for Biomedical Engineering, Department of Information Technology and Electrical Engineering, Zurich, Switzerland
| | - Shy Shoham
- NYU Langone Health, Neuroscience Institutes, Department of Ophthalmology and Tech4Health New York, United States
| | - Daniel Razansky
- University of Zurich, Institute for Biomedical Engineering and Institute of Pharmacology and Toxicology, Faculty of Medicine, Zurich, Switzerland
- ETH Zurich, Institute for Biomedical Engineering, Department of Information Technology and Electrical Engineering, Zurich, Switzerland
- ETH AI Center, Zurich, Switzerland
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6
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Monteiro T, Rodrigues FS, Pexirra M, Cruz BF, Gonçalves AI, Rueda-Orozco PE, Paton JJ. Using temperature to analyze the neural basis of a time-based decision. Nat Neurosci 2023; 26:1407-1416. [PMID: 37443279 DOI: 10.1038/s41593-023-01378-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2020] [Accepted: 06/12/2023] [Indexed: 07/15/2023]
Abstract
The basal ganglia are thought to contribute to decision-making and motor control. These functions are critically dependent on timing information, which can be extracted from the evolving state of neural populations in their main input structure, the striatum. However, it is debated whether striatal activity underlies latent, dynamic decision processes or kinematics of overt movement. Here, we measured the impact of temperature on striatal population activity and the behavior of rats, and compared the observed effects with neural activity and behavior collected in multiple versions of a temporal categorization task. Cooling caused dilation, and warming contraction, of both neural activity and patterns of judgment in time, mimicking endogenous decision-related variability in striatal activity. However, temperature did not similarly affect movement kinematics. These data provide compelling evidence that the timecourse of evolving striatal activity dictates the speed of a latent process that is used to guide choices, but not continuous motor control. More broadly, they establish temporal scaling of population activity as a likely neural basis for variability in timing behavior.
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Affiliation(s)
- Tiago Monteiro
- Neuroscience Programme, Champalimaud Foundation, Lisbon, Portugal
- Department of Biology, University of Oxford, Oxford, UK
| | | | - Margarida Pexirra
- Neuroscience Programme, Champalimaud Foundation, Lisbon, Portugal
- Sainsbury Wellcome Centre for Neural Circuits and Behaviour, University College London, London, UK
| | - Bruno F Cruz
- Neuroscience Programme, Champalimaud Foundation, Lisbon, Portugal
- NeuroGEARS Ltd., London, UK
| | - Ana I Gonçalves
- Neuroscience Programme, Champalimaud Foundation, Lisbon, Portugal
| | | | - Joseph J Paton
- Neuroscience Programme, Champalimaud Foundation, Lisbon, Portugal.
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7
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Robbe D, Safaie M. Hot times for the dorsal striatum. Nat Neurosci 2023; 26:1320-1321. [PMID: 37443280 DOI: 10.1038/s41593-023-01386-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/15/2023]
Affiliation(s)
- David Robbe
- Institut de Neurobiologie de la Méditerranée (INMED), INSERM, Turing Center for Living System, Aix Marseille Université, Marseille, France.
| | - Mostafa Safaie
- Department of Bioengineering, Imperial College London, London, UK
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8
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Langdon C, Genkin M, Engel TA. A unifying perspective on neural manifolds and circuits for cognition. Nat Rev Neurosci 2023; 24:363-377. [PMID: 37055616 PMCID: PMC11058347 DOI: 10.1038/s41583-023-00693-x] [Citation(s) in RCA: 19] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/06/2023] [Indexed: 04/15/2023]
Abstract
Two different perspectives have informed efforts to explain the link between the brain and behaviour. One approach seeks to identify neural circuit elements that carry out specific functions, emphasizing connectivity between neurons as a substrate for neural computations. Another approach centres on neural manifolds - low-dimensional representations of behavioural signals in neural population activity - and suggests that neural computations are realized by emergent dynamics. Although manifolds reveal an interpretable structure in heterogeneous neuronal activity, finding the corresponding structure in connectivity remains a challenge. We highlight examples in which establishing the correspondence between low-dimensional activity and connectivity has been possible, unifying the neural manifold and circuit perspectives. This relationship is conspicuous in systems in which the geometry of neural responses mirrors their spatial layout in the brain, such as the fly navigational system. Furthermore, we describe evidence that, in systems in which neural responses are heterogeneous, the circuit comprises interactions between activity patterns on the manifold via low-rank connectivity. We suggest that unifying the manifold and circuit approaches is important if we are to be able to causally test theories about the neural computations that underlie behaviour.
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Affiliation(s)
- Christopher Langdon
- Princeton Neuroscience Institute, Princeton University, Princeton, NJ, USA
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY, USA
| | - Mikhail Genkin
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY, USA
| | - Tatiana A Engel
- Princeton Neuroscience Institute, Princeton University, Princeton, NJ, USA.
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY, USA.
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9
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Banerjee A, Chen F, Druckmann S, Long MA. Neural dynamics in the rodent motor cortex enables flexible control of vocal timing. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.01.23.525252. [PMID: 36747850 PMCID: PMC9900850 DOI: 10.1101/2023.01.23.525252] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Neocortical activity is thought to mediate voluntary control over vocal production, but the underlying neural mechanisms remain unclear. In a highly vocal rodent, the Alston's singing mouse, we investigate neural dynamics in the orofacial motor cortex (OMC), a structure critical for vocal behavior. We first describe neural activity that is modulated by component notes (approx. 100 ms), likely representing sensory feedback. At longer timescales, however, OMC neurons exhibit diverse and often persistent premotor firing patterns that stretch or compress with song duration (approx. 10 s). Using computational modeling, we demonstrate that such temporal scaling, acting via downstream motor production circuits, can enable vocal flexibility. These results provide a framework for studying hierarchical control circuits, a common design principle across many natural and artificial systems.
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Affiliation(s)
- Arkarup Banerjee
- NYU Neuroscience Institute, New York University Langone Health, New York, NY 10016, USA
- Department of Otolaryngology, New York University Langone Health, New York, NY 10016, USA
- Center for Neural Science, New York University, New York, NY 10003, USA
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY 11724, USA
| | - Feng Chen
- Department of Applied Physics, Stanford University, Stanford, CA 94305, USA
| | - Shaul Druckmann
- Department of Neuroscience, Stanford University, Stanford, CA 94304, USA
| | - Michael A Long
- NYU Neuroscience Institute, New York University Langone Health, New York, NY 10016, USA
- Department of Otolaryngology, New York University Langone Health, New York, NY 10016, USA
- Center for Neural Science, New York University, New York, NY 10003, USA
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY 11724, USA
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10
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Gonzalez-Suarez AD, Zavatone-Veth JA, Chen J, Matulis CA, Badwan BA, Clark DA. Excitatory and inhibitory neural dynamics jointly tune motion detection. Curr Biol 2022; 32:3659-3675.e8. [PMID: 35868321 PMCID: PMC9474608 DOI: 10.1016/j.cub.2022.06.075] [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: 01/09/2022] [Revised: 05/03/2022] [Accepted: 06/24/2022] [Indexed: 11/26/2022]
Abstract
Neurons integrate excitatory and inhibitory signals to produce their outputs, but the role of input timing in this integration remains poorly understood. Motion detection is a paradigmatic example of this integration, since theories of motion detection rely on different delays in visual signals. These delays allow circuits to compare scenes at different times to calculate the direction and speed of motion. Different motion detection circuits have different velocity sensitivity, but it remains untested how the response dynamics of individual cell types drive this tuning. Here, we sped up or slowed down specific neuron types in Drosophila's motion detection circuit by manipulating ion channel expression. Altering the dynamics of individual neuron types upstream of motion detectors increased their sensitivity to fast or slow visual motion, exposing distinct roles for excitatory and inhibitory dynamics in tuning directional signals, including a role for the amacrine cell CT1. A circuit model constrained by functional data and anatomy qualitatively reproduced the observed tuning changes. Overall, these results reveal how excitatory and inhibitory dynamics together tune a canonical circuit computation.
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Affiliation(s)
| | - Jacob A Zavatone-Veth
- Department of Physics, Harvard University, Cambridge, MA 02138, USA; Center for Brain Science, Harvard University, Cambridge, MA 02138, USA
| | - Juyue Chen
- Interdepartmental Neuroscience Program, Yale University, New Haven, CT 06511, USA
| | | | - Bara A Badwan
- School of Engineering and Applied Science, Yale University, New Haven, CT 06511, USA
| | - Damon A Clark
- Interdepartmental Neuroscience Program, Yale University, New Haven, CT 06511, USA; Department of Physics, Yale University, New Haven, CT 06511, USA; Department of Molecular, Cellular, and Developmental Biology, Yale University, New Haven, CT 06511, USA; Department of Neuroscience, Yale University, New Haven, CT 06511, USA.
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11
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Niesvizky-Kogan I, Bass M, Goldenholz SR, Goldenholz DM. Focal Cooling for Drug-Resistant Epilepsy: A Review. JAMA Neurol 2022; 79:937-944. [PMID: 35877102 PMCID: PMC10101767 DOI: 10.1001/jamaneurol.2022.1936] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
Importance Epilepsy affects at least 1.2% of the population, with one-third of cases considered to be drug-resistant epilepsy (DRE). For these cases, focal cooling therapy may be a potential avenue for treatment, offering hope to people with DRE for freedom from seizure. The therapy leverages neuroscience and engineering principles to deliver a reversible treatment unhindered by pharmacology. Observations Analogous to (but safer than) the use of global cooling in postcardiac arrest and neonatal ischemic injury, extensive research supports the premise that focal cooling as a long-term treatment for epilepsy could be effective. The potential advantages of focal cooling are trifold: stopping epileptiform discharges, seizures, and status epilepticus safely across species (including humans). Conclusions and Relevance This Review presents the most current evidence supporting focal cooling in epilepsy. Cooling has been demonstrated as a potentially safe and effective treatment modality for DRE, although it is not yet ready for use in humans outside of randomized clinical trials. The Review will also offer a brief overview of the technical challenges related to focal cooling in humans, including the optimal device design and cooling parameters.
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Affiliation(s)
- Itamar Niesvizky-Kogan
- Harvard Medical School, Boston, Massachusetts.,Beth Israel Deaconess Medical Center, Boston, Massachusetts
| | | | | | - Daniel M Goldenholz
- Harvard Medical School, Boston, Massachusetts.,Beth Israel Deaconess Medical Center, Boston, Massachusetts
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12
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Rzechorzek NM, Thrippleton MJ, Chappell FM, Mair G, Ercole A, Cabeleira M, Rhodes J, Marshall I, O'Neill JS. A daily temperature rhythm in the human brain predicts survival after brain injury. Brain 2022; 145:2031-2048. [PMID: 35691613 PMCID: PMC9336587 DOI: 10.1093/brain/awab466] [Citation(s) in RCA: 41] [Impact Index Per Article: 20.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2021] [Revised: 11/03/2021] [Accepted: 11/20/2021] [Indexed: 02/06/2023] Open
Abstract
Patients undergo interventions to achieve a 'normal' brain temperature; a parameter that remains undefined for humans. The profound sensitivity of neuronal function to temperature implies the brain should be isothermal, but observations from patients and non-human primates suggest significant spatiotemporal variation. We aimed to determine the clinical relevance of brain temperature in patients by establishing how much it varies in healthy adults. We retrospectively screened data for all patients recruited to the Collaborative European NeuroTrauma Effectiveness Research in Traumatic Brain Injury (CENTER-TBI) High Resolution Intensive Care Unit Sub-Study. Only patients with direct brain temperature measurements and without targeted temperature management were included. To interpret patient analyses, we prospectively recruited 40 healthy adults (20 males, 20 females, 20-40 years) for brain thermometry using magnetic resonance spectroscopy. Participants were scanned in the morning, afternoon, and late evening of a single day. In patients (n = 114), brain temperature ranged from 32.6 to 42.3°C and mean brain temperature (38.5 ± 0.8°C) exceeded body temperature (37.5 ± 0.5°C, P < 0.0001). Of 100 patients eligible for brain temperature rhythm analysis, 25 displayed a daily rhythm, and the brain temperature range decreased in older patients (P = 0.018). In healthy participants, brain temperature ranged from 36.1 to 40.9°C; mean brain temperature (38.5 ± 0.4°C) exceeded oral temperature (36.0 ± 0.5°C) and was 0.36°C higher in luteal females relative to follicular females and males (P = 0.0006 and P < 0.0001, respectively). Temperature increased with age, most notably in deep brain regions (0.6°C over 20 years, P = 0.0002), and varied spatially by 2.41 ± 0.46°C with highest temperatures in the thalamus. Brain temperature varied by time of day, especially in deep regions (0.86°C, P = 0.0001), and was lowest at night. From the healthy data we built HEATWAVE-a 4D map of human brain temperature. Testing the clinical relevance of HEATWAVE in patients, we found that lack of a daily brain temperature rhythm increased the odds of death in intensive care 21-fold (P = 0.016), whilst absolute temperature maxima or minima did not predict outcome. A warmer mean brain temperature was associated with survival (P = 0.035), however, and ageing by 10 years increased the odds of death 11-fold (P = 0.0002). Human brain temperature is higher and varies more than previously assumed-by age, sex, menstrual cycle, brain region, and time of day. This has major implications for temperature monitoring and management, with daily brain temperature rhythmicity emerging as one of the strongest single predictors of survival after brain injury. We conclude that daily rhythmic brain temperature variation-not absolute brain temperature-is one way in which human brain physiology may be distinguished from pathophysiology.
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Affiliation(s)
| | - Michael J Thrippleton
- Edinburgh Imaging (Royal Infirmary of Edinburgh) Facility, Edinburgh EH16 4SA, UK.,Centre for Clinical Brain Sciences, University of Edinburgh, Edinburgh EH16 4SB, UK
| | - Francesca M Chappell
- Centre for Clinical Brain Sciences, University of Edinburgh, Edinburgh EH16 4SB, UK
| | - Grant Mair
- Edinburgh Imaging (Royal Infirmary of Edinburgh) Facility, Edinburgh EH16 4SA, UK.,Centre for Clinical Brain Sciences, University of Edinburgh, Edinburgh EH16 4SB, UK
| | - Ari Ercole
- Division of Anaesthesia, University of Cambridge, Box 93 Addenbrooke's Hospital, Cambridge CB2 0QQ, UK
| | - Manuel Cabeleira
- Division of Neurosurgery, Department of Clinical Neurosciences, University of Cambridge, Box 167, Cambridge Biomedical Campus, Addenbrooke's Hospital, Cambridge CB2 0QQ, UK
| | | | - Jonathan Rhodes
- Department of Anaesthesia, Critical Care and Pain Medicine, NHS Lothian, Room No. S8208 (2nd Floor), Royal Infirmary of Edinburgh, Edinburgh EH16 4SA, UK
| | - Ian Marshall
- Edinburgh Imaging (Royal Infirmary of Edinburgh) Facility, Edinburgh EH16 4SA, UK.,Centre for Clinical Brain Sciences, University of Edinburgh, Edinburgh EH16 4SB, UK
| | - John S O'Neill
- MRC Laboratory of Molecular Biology, Cambridge CB2 0QH, UK
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13
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Masset P, Qin S, Zavatone-Veth JA. Drifting neuronal representations: Bug or feature? BIOLOGICAL CYBERNETICS 2022; 116:253-266. [PMID: 34993613 DOI: 10.1007/s00422-021-00916-3] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/25/2021] [Accepted: 11/17/2021] [Indexed: 06/14/2023]
Abstract
The brain displays a remarkable ability to sustain stable memories, allowing animals to execute precise behaviors or recall stimulus associations years after they were first learned. Yet, recent long-term recording experiments have revealed that single-neuron representations continuously change over time, contravening the classical assumption that learned features remain static. How do unstable neural codes support robust perception, memories, and actions? Here, we review recent experimental evidence for such representational drift across brain areas, as well as dissections of its functional characteristics and underlying mechanisms. We emphasize theoretical proposals for how drift need not only be a form of noise for which the brain must compensate. Rather, it can emerge from computationally beneficial mechanisms in hierarchical networks performing robust probabilistic computations.
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Affiliation(s)
- Paul Masset
- Center for Brain Science, Harvard University, Cambridge, MA, USA.
- Department of Molecular and Cellular Biology, Harvard University, Cambridge, MA, USA.
| | - Shanshan Qin
- Center for Brain Science, Harvard University, Cambridge, MA, USA
- School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, USA
| | - Jacob A Zavatone-Veth
- Center for Brain Science, Harvard University, Cambridge, MA, USA
- Department of Physics, Harvard University, Cambridge, MA, USA
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14
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Elmaleh M, Kranz D, Asensio AC, Moll FW, Long MA. Sleep replay reveals premotor circuit structure for a skilled behavior. Neuron 2021; 109:3851-3861.e4. [PMID: 34626537 DOI: 10.1016/j.neuron.2021.09.021] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2021] [Revised: 08/12/2021] [Accepted: 09/13/2021] [Indexed: 10/20/2022]
Abstract
Neural circuits often exhibit sequences of activity, but the contribution of local networks to their generation remains unclear. In the zebra finch, song-related premotor sequences within HVC may result from some combination of local connectivity and long-range thalamic inputs from nucleus uvaeformis (Uva). Because lesions to either structure abolish song, we examine "sleep replay" using high-density recording methods to reconstruct precise song-related events. Replay activity persists after the upstream nucleus interfacialis of the nidopallium is lesioned and slows when HVC is cooled, demonstrating that HVC provides temporal structure for these events. To further gauge the importance of intra-HVC connectivity for shaping network dynamics, we lesion Uva during sleep and find that residual replay sequences could span syllable boundaries, supporting a model in which HVC can propagate sequences throughout the duration of the song. Our results highlight the power of studying offline activity to investigate behaviorally relevant circuit organization.
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Affiliation(s)
- Margot Elmaleh
- NYU Neuroscience Institute and Department of Otolaryngology, New York University Langone Medical Center, New York, NY 10016, USA; Center for Neural Science, New York University, New York, NY 10003, USA
| | - Devorah Kranz
- NYU Neuroscience Institute and Department of Otolaryngology, New York University Langone Medical Center, New York, NY 10016, USA; Center for Neural Science, New York University, New York, NY 10003, USA
| | - Ariadna Corredera Asensio
- NYU Neuroscience Institute and Department of Otolaryngology, New York University Langone Medical Center, New York, NY 10016, USA; Center for Neural Science, New York University, New York, NY 10003, USA
| | - Felix W Moll
- NYU Neuroscience Institute and Department of Otolaryngology, New York University Langone Medical Center, New York, NY 10016, USA; Center for Neural Science, New York University, New York, NY 10003, USA
| | - Michael A Long
- NYU Neuroscience Institute and Department of Otolaryngology, New York University Langone Medical Center, New York, NY 10016, USA; Center for Neural Science, New York University, New York, NY 10003, USA.
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