Tactile edges and motion via patterned microstimulation of the human somatosensory cortex

Science, Journal Year: 2025, Volume and Issue: 387(6731), P. 315 - 322

Published: Jan. 16, 2025

Intracortical microstimulation (ICMS) of somatosensory cortex evokes tactile sensations whose properties can be systematically manipulated by varying stimulation parameters. However, ICMS currently provides an imperfect sense touch, limiting manual dexterity and experience. Leveraging our understanding how features are encoded in the primary (S1), we sought to inform individuals with paralysis about local geometry apparent motion objects on their skin. We simultaneously delivered through electrodes spatially patterned projected fields (PFs), evoking edges. then created complex PFs that encode arbitrary shapes skin indentation patterns. By delivering spatiotemporally ICMS, evoked sensation across skin, speed direction which could controlled. Thus, improved individuals’ experience use brain-controlled bionic hands.

Language: Английский

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Cortical dynamics in hand/forelimb S1 and M1 evoked by brief photostimulation of the mouse’s hand

eLife, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 31, 2025

Spiking activity along synaptic circuits linking primary somatosensory (S1) and motor (M1) areas is fundamental for sensorimotor integration in cortex. Circuits the ascending pathway through mouse hand/forelimb S1 M1 were recently described detail (Yamawaki et al., 2021). Here, we characterize peripherally evoked spiking dynamics these two cortical areas. Brief (5 ms) optogenetic photostimulation of hand generated short (~25 barrages first (onset latency 15 then (10 ms later). The estimated propagation speed was 20-fold faster from to than M1. Amplitudes strongly attenuated. Responses typically triphasic, with suppression rebound following initial peak. Evoked biased middle layers, consistent thalamocortical connectivity, while that upper corticocortical connectivity. Parvalbumin (PV) inhibitory interneurons involved each phase, accounting three quarters spikes S1, their selective sufficed evoke both Partial silencing by PV activation during stimulation reduced sensory responses. Overall, results how propagates transcortical loop, illuminate vivo relate underlying circuit organization this system.

Language: Английский

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Cortical dynamics in hand/forelimb S1 and M1 evoked by brief photostimulation of the mouse’s hand

Published: Jan. 31, 2025

Spiking activity along synaptic circuits linking primary somatosensory (S1) and motor (M1) areas is fundamental for sensorimotor integration in cortex. Circuits the ascending pathway through mouse hand/forelimb S1 M1 were recently described detail (Yamawaki et al., 2021). Here, we characterize peripherally evoked spiking dynamics these two cortical same system. Brief (5 ms) optogenetic photostimulation of hand generated short (∼25 barrages first (onset latency 15 then (10 ms later). The estimated propagation speed was 20-fold faster from to than M1. Response amplitudes strongly attenuated approximately a third those S1. Responses typically triphasic, with suppression rebound following initial peak. Parvalbumin (PV) inhibitory interneurons involved each phase, accounting three-quarters spikes S1, their selective sufficed evoke both Partial silencing by PV activation during stimulation reduced sensory responses. These results provide quantitative measures hand/forelimb-related transcortical loop; demonstrate prominent mechanistic role neurons phase response; and, support conceptual model which signals reach via high-speed subcortical generate characteristic activity, densely polysynaptic corticocortical similar but delayed profile activity.

Language: Английский

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Degradation-aware neural imputation: Advancing decoding stability in brain machine interfaces

APL Bioengineering, Journal Year: 2025, Volume and Issue: 9(2)

Published: April 16, 2025

Neural signal degradation poses a significant challenge in maintaining stable performance when decoding motor tasks using multiunit activity (MUA) and local field potential (LFP) signals the implantable brain machine interface (iBMI) applications. Effective methods for imputing degraded or missing are essential to restore neural integrity, thereby improving accuracy system robustness over long-term recordings with fluctuating quality. This study introduces confidence-weighted Bayesian linear regression (CW-BLR) approach impute affected by degradation, enhancing consistency of decoding. The CW-BLR was compared traditional methods—mean imputation (Mean-imp) Gaussian-mixture-model-based expectation–maximization (GMM-EM)—using kernel-sliced inverse (kSIR) decoder evaluate outcomes. Four Wistar rats were trained perform forelimb-reaching task while (MUA LFPs) recorded 27 days. imputed during days 8–27. Decoding evaluated kSIR Mean-imp GMM-EM. demonstrated superior effectively preserving both temporal spatial dependencies within signals. CW-BLR-imputed data significantly improved methods, showing consistently higher performance, particularly quality from period. offers robust effective framework iBMI applications, addressing challenges accurate prolonged recordings. By utilizing confidence-based metrics, surpasses providing across scenarios.

Language: Английский

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Intensity-Dependent Tacs Entrainment Effects in a Cortical Microcircuit: A Computational Study

Published: Jan. 1, 2025

Language: Английский

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Cortical dynamics in hand/forelimb S1 and M1 evoked by brief photostimulation of the mouse’s hand

Published: May 2, 2025

Spiking activity along synaptic circuits linking primary somatosensory (S1) and motor (M1) areas is fundamental for sensorimotor integration in cortex. Circuits the ascending pathway through mouse hand/forelimb S1 M1 were recently described detail (Yamawaki et al., 2021). Here, we characterize peripherally evoked spiking dynamics these two cortical areas. Brief (5 ms) optogenetic photostimulation of hand generated short (∼25 barrages first (onset latency 15 then (10 ms later). The estimated propagation speed was 20-fold faster from to than M1. Amplitudes strongly attenuated. Responses typically triphasic, with suppression rebound following initial peak. Evoked biased middle layers, consistent thalamocortical connectivity, while that upper corticocortical connectivity. Parvalbumin (PV) inhibitory interneurons involved each phase, accounting three quarters spikes S1, their selective sufficed evoke both Partial silencing by PV activation during stimulation reduced sensory responses. Overall, results how propagates transcortical loop, illuminate vivo relate underlying circuit organization this system.

Language: Английский

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Cortical dynamics in hand/forelimb S1 and M1 evoked by brief photostimulation of the mouse’s hand

eLife, Journal Year: 2025, Volume and Issue: 14

Published: May 19, 2025

Spiking activity along synaptic circuits linking primary somatosensory (S1) and motor (M1) areas is fundamental for sensorimotor integration in cortex. Circuits the ascending pathway through mouse hand/forelimb S1 M1 were recently described detail (Yamawaki et al., 2021). Here, we characterize peripherally evoked spiking dynamics these two cortical areas. Brief (5 ms) optogenetic photostimulation of hand generated short (~25 barrages first (onset latency 15 then (10 ms later). The estimated propagation speed was 20-fold faster from to than M1. Amplitudes strongly attenuated. Responses typically triphasic, with suppression rebound following initial peak. Evoked biased middle layers, consistent thalamocortical connectivity, while that upper corticocortical connectivity. Parvalbumin (PV) inhibitory interneurons involved each phase, accounting three quarters spikes S1, their selective sufficed evoke both Partial silencing by PV activation during stimulation reduced sensory responses. Overall, results how propagates transcortical loop, illuminate vivo relate underlying circuit organization this system.

Language: Английский

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TACTILE EDGES AND MOTION VIA PATTERNED MICROSTIMULATION OF THE HUMAN CORTEX

medRxiv (Cold Spring Harbor Laboratory), Journal Year: 2024, Volume and Issue: unknown

Published: May 7, 2024

Intracortical microstimulation (ICMS) of somatosensory cortex evokes tactile sensations whose location and properties can be systematically manipulated by varying the electrode stimulation parameters 1–3 . This phenomenon used to convey feedback from a brain-controlled bionic hand about object interactions. However, ICMS currently provides an impoverished sense touch, limiting dexterous manipulation conscious experience neuroprosthetic systems. Leveraging our understanding how these sensory features are encoded in S1 4,5 , we sought expand repertoire ICMS-based artificial touch provide information local geometry motion objects individuals with paralysis. First, simultaneously delivered through multiple, spatially patterned electrodes, adopting specific arrangements aligned projected fields (PFs). Unprompted, participants reported sensation edge. Next, created more complex PFs found that could intuitively perceive arbitrary shapes skin indentation patterns. By delivering sequentially electrodes discontinuous PFs, even evoke across skin, direction speed which were able manipulate. We conclude appropriate spatiotemporal patterning inspired coding sensations. Our findings serve push boundaries thereby enriching participants’ simple percepts highly informative mimic natural touch.

Language: Английский

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Spatially and temporally mismatched blood flow and neuronal activity by high-intensity intracortical microstimulation

Brain stimulation, Journal Year: 2025, Volume and Issue: unknown

Published: April 1, 2025

Intracortial microstimulation (ICMS) is widely used in neuroprosthetic brain-machine interfacing, particularly restoring lost sensory and motor functions. Spiking neuronal activity requires increased cerebral blood flow to meet local metabolic demands, a process conventionally denoted as neurovascular coupling (NVC). However, it unknown precisely how what extent ICMS elicits NVC the responses correlate. Suboptimal by may compromise oxygen energy delivery activated neurons thus impair functionality. We wide-field imaging (WFI), laser speckle (LSI) two-photon microscopy (TPM) study living, transgenic mice expressing calcium (Ca2+) fluorescent indicators either or vascular mural cells (VMC), well measure inner lumen diameters. By testing range of stimulation amplitudes examining cortical tissue at different distances from stimulating electrode tip, we found that high intensities (≥ 50 μA) elicited spatial temporal decoupling regions most adjacent tip (< 200 μm), with significantly delayed onset times compromised maximum increases. attribute these effects respectively Ca2+ signalling decreased sensitivity VMCs. Our offers new insights into ICMS-associated physiology potentially critical implications towards optimal design therapies: low preserve NVC; disrupt precipitate supply deficits.

Language: Английский

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Cortical dynamics in hand/forelimb S1 and M1 evoked by brief photostimulation of the mouse’s hand

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2024, Volume and Issue: unknown

Published: Dec. 4, 2024

Spiking activity along synaptic circuits linking primary somatosensory (S1) and motor (M1) areas is fundamental for sensorimotor integration in cortex. Circuits the ascending pathway through mouse hand/forelimb S1 M1 were recently described detail (Yamawaki et al., 2021). Here, we characterize peripherally evoked spiking dynamics these two cortical same system. Brief (5 ms) optogenetic photostimulation of hand generated short (∼25 barrages first (onset latency 15 then (10 ms later). The estimated propagation speed was 20-fold faster from to than M1. Response amplitudes strongly attenuated approximately a third those S1. Responses typically triphasic, with suppression rebound following initial peak. Parvalbumin (PV) inhibitory interneurons involved each phase, accounting three-quarters spikes S1, their selective sufficed evoke both Partial silencing by PV activation during stimulation reduced sensory responses. These results provide quantitative measures hand/forelimb-related transcortical loop; demonstrate prominent mechanistic role neurons phase response; and, support conceptual model which signals reach via high-speed subcortical generate characteristic activity, densely polysynaptic corticocortical similar but delayed profile activity.

Language: Английский

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