Biomimetic multi-channel microstimulation of somatosensory cortex conveys high resolution force feedback for bionic hands

bioRxiv (Cold Spring Harbor Laboratory), Год журнала: 2023, Номер unknown

Опубликована: Фев. 18, 2023

Manual interactions with objects are supported by tactile signals from the hand. This feedback can be restored in brain-controlled bionic hands via intracortical microstimulation (ICMS) of somatosensory cortex (S1). In ICMS-based feedback, contact force signaled modulating stimulation intensity based on output sensors hand, which turn modulates perceived magnitude sensation. present study, we gauged dynamic range and precision three human participants implanted arrays microelectrodes S1. To this end, measured increases sensation resulting ICMS amplitude participant's ability to distinguish between different levels. We then assessed whether could improve fidelity implementing "biomimetic" ICMS-trains, designed evoke patterns neuronal activity that more closely mimic those natural touch, delivering through multiple channels at once. found multi-channel biomimetic gives rise stronger distinguishable sensations than does its single-channel counterpart. Finally, implemented a hand had participant perform compliance discrimination task. yielded improved over linear conclude conveys finely graded approximates sensitivity conferred touch.

Язык: Английский

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Neural mechanisms of the temporal response of cortical neurons to intracortical microstimulation

Brain stimulation, Год журнала: 2024, Номер 17(2), С. 365 - 381

Опубликована: Март 1, 2024

Background:Intracortical microstimulation (ICMS) is used to map neuronal circuitry in the brain and restore lost sensory function, including vision, hearing, somatosensation. The temporal response of cortical neurons single pulse ICMS remarkably stereotyped comprises short latency excitation followed by prolonged inhibition and, some cases, rebound excitation. However, neural origin different components are poorly understood, interactions between three during trains pulses remains unclear.Objective:We computational modeling determine mechanisms contributing model neurons.Methods:We implemented a biophysically based column comprising with realistic morphology synapses quantified protocols. We characterized responses across stimulation intensities inhibitory (GABA-B/GABA-A) synaptic strengths. To probe components, we paired at inter-pulse intervals frequencies. Finally, evaluated performance biomimetic evoking sustained responses.Results:Single evoked period inhibition, but did not exhibit post-inhibitory strength increased duration amplitude. Prolonged resulted from both after-hyperpolarization currents GABA-B transmission. During protocol, test decreased marginally compared those for interpulse (IPI) < 100 ms. Further, was IPIs <50ms predicted linear superposition individual responses. For IPIs>50 ms, comparable pulse. Short repetitive excitatory against background inhibition. declined higher cessation frequencies following Biomimetic onset offset phases despite presence induced inhibition.Conclusions:The replicated long-lasting documented experimental studies ICMS. Both cellular influenced generated non-linear dynamic ICMS-evoked activity may play an important role mediating ICMS-induced precepts.

Язык: Английский

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Tessellation of artificial touch via microstimulation of human somatosensory cortex

bioRxiv (Cold Spring Harbor Laboratory), Год журнала: 2023, Номер unknown

Опубликована: Июнь 26, 2023

When we interact with objects, rely on signals from the hand that convey information about object and our interaction it. A basic feature of these interactions, locations contacts between object, is often only available via sense touch. Information contact a brain-controlled bionic an can be signaled intracortical microstimulation (ICMS) somatosensory cortex (S1), which evokes touch sensations are localized to specific patch skin. To provide intuitive location information, tactile sensors robotic drive ICMS through electrodes evoke at skin matching sensor locations. This approach requires ICMS-evoked focal, stable, distributed over hand. systematically investigate localization sensations, analyzed projected fields (PFs) - their spatial extent reports obtained multiple years three participants implanted microelectrode arrays in S1. First, found PFs vary widely size across electrodes, highly stable within electrode, large swaths each participant's hand, increase as amplitude or frequency increases. Second, while PF match receptive (RFs) neurons near stimulating tend subsumed by corresponding RFs. Third, multi-channel stimulation gives rise reflects conjunction component channels. By largely overlapping PFs, then, sensation experienced primarily intersection PFs. assess functional consequence this phenomenon, implemented multichannel ICMS-based feedback demonstrated resulting more localizable than those evoked single-channel ICMS.

Язык: Английский

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Activity-dependent recruitment of inhibition and excitation in the awake mammalian cortex during electrical stimulation

Neuron, Год журнала: 2023, Номер 112(5), С. 821 - 834.e4

Опубликована: Дек. 21, 2023

Язык: Английский

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Dynamic amplitude modulation of microstimulation evokes biomimetic onset and offset transients and reduces depression of evoked calcium responses in sensory cortices

Brain stimulation, Год журнала: 2023, Номер 16(3), С. 939 - 965

Опубликована: Май 1, 2023

Intracortical microstimulation (ICMS) is an emerging approach to restore sensation people with neurological injury or disease. Biomimetic microstimulation, stimulus trains that mimic neural activity in the brain through encoding of onset and offset transients, could improve utility ICMS for brain-computer interface (BCI) applications, but how biomimetic affects activation not understood. Current "biomimetic" aim reproduce strong transients evoked by sensory input dynamic modulation parameters. Stimulus induced depression (decreases intensity over time) also a potential barrier clinical implementation feedback, may reduce this effect.

Язык: Английский

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Characterization and closed-loop control of infrared thalamocortical stimulation produces spatially constrained single-unit responses

PNAS Nexus, Год журнала: 2024, Номер 3(2)

Опубликована: Фев. 1, 2024

Abstract Deep brain stimulation (DBS) is a powerful tool for the treatment of circuitopathy-related neurological and psychiatric diseases disorders such as Parkinson's disease obsessive-compulsive disorder, well critical research perturbing neural circuits exploring neuroprostheses. Electrically mediated DBS, however, limited by spread stimulus currents into tissue unrelated to course treatment, potentially causing undesirable patient side effects. In this work, we utilize infrared (INS), an optical neuromodulation technique that uses near midinfrared light drive graded excitatory inhibitory responses in nerves neurons, facilitate spatially constrained DBS paradigm. INS has been shown provide cortical neurons and, unlike other techniques, does not require genetic modification target. We show produces graded, biophysically relevant single-unit with robust information transfer rat thalamocortical circuits. Importantly, activation from thalamic more response profiles than conventional electrical stimulation. Owing observed spatial precision INS, used deep reinforcement learning (RL) closed-loop control circuits, creating real-time representations stimulus-response dynamics while driving precise firing patterns. Our data suggest can serve targeted dynamic paradigm both open DBS.

Язык: Английский

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Evoking stable and precise tactile sensations via multi-electrode intracortical microstimulation of the somatosensory cortex

Nature Biomedical Engineering, Год журнала: 2024, Номер unknown

Опубликована: Дек. 6, 2024

Tactile feedback from brain-controlled bionic hands can be partially restored via intracortical microstimulation (ICMS) of the primary somatosensory cortex. In ICMS, location percepts depends on electrode's and percept intensity stimulation frequency amplitude. Sensors a hand thus linked to somatotopically appropriate electrodes, contact force each sensor used determine amplitude stimulus. Here we report systematic investigation localization ICMS-evoked in three participants with cervical spinal cord injury. A retrospective analysis projected fields showed that they were typically composed focal hotspot diffuse borders, arrayed keeping their underlying receptive stable throughout duration study. When testing participants' ability rapidly localize single ICMS presentation, individual electrodes evoked only weak sensations, making object discrimination difficult. However, overlapping multiple produced more localizable intense sensations allowed for precise use hand. An injury shows produce are easily localizable.

Язык: Английский

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Activation and depression of neural and hemodynamic responses induced by the intracortical microstimulation and visual stimulation in the mouse visual cortex

Journal of Neural Engineering, Год журнала: 2024, Номер 21(2), С. 026033 - 026033

Опубликована: Март 27, 2024

Abstract Objective . Intracortical microstimulation (ICMS) can be an effective method for restoring sensory perception in contemporary brain–machine interfaces. However, the mechanisms underlying better control of neuronal responses remain poorly understood, as well relationship between activity and other concomitant phenomena occurring around stimulation site. Approach Different frequencies were investigated vivo on Thy1-GCaMP6s mice using widefield two-photon imaging to evaluate evoked excitatory neural across multiple spatial scales induced hemodynamic responses. Specifically, we quantified stimulation-induced activation depression mouse visual cortex measured oxyhemoglobin deoxyhemoglobin signals mesoscopic-scale imaging. Main results Our calcium findings revealed a preference lower-frequency driving stronger activation. A depressive response following preferred slightly higher frequency compared Hemodynamic exhibited comparable spread signals. Oxyhemoglobin concentration site remained elevated during post-activation (depression) period. Somatic neuropil by microscopy showed similar dependence parameters, although magnitudes soma was greater than neuropil. Furthermore, higher-frequency more pronounced neuropil, while predominantly irrespective frequencies. Significance These suggest that mechanism differs from activation, requiring ample oxygen supply, affecting neurons. provide novel understanding ICMS offer insights into neuro-devices utilize both achieve desired

Язык: Английский

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Inkjet-printed transparent electrodes: Design, characterization, and initial in vivo evaluation for brain stimulation

PLoS ONE, Год журнала: 2025, Номер 20(4), С. e0320376 - e0320376

Опубликована: Апрель 1, 2025

Electrical stimulation is a powerful tool for investigating and modulating brain activity, as well treating neurological disorders. However, understanding the precise effects of electrical on neural activity has been hindered by limitations in recording neuronal responses near stimulating electrode, such artifacts electrophysiology or obstruction field view imaging. In this study, we introduce novel device fabricated from conductive polymers that transparent therefore compatible with optical imaging techniques. The manufactured using combination microfabrication inkjet printing techniques flexible, allowing better adherence to brain’s natural curvature. We characterized properties electrodes, focusing trade-off between maximum current can be delivered transmittance. found 1 mm diameter, 350 nm thick PEDOT:PSS electrode could used apply 130 μA while maintaining 84% transmittance (approximately 50% under 2-photon conditions). then evaluated performance an anesthetized mouse measuring electric nearby values up 30 V/m. Finally, combined experimental data finite-element model vivo setup estimate distribution underneath brain. Our findings indicate generate high 300 V/m directly beneath demonstrating its potential studying manipulating range relevant human applications. Overall, work presents promising approach developing versatile new tools study stimulation.

Язык: Английский

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Rapid learning and integration of artificial sensation

bioRxiv (Cold Spring Harbor Laboratory), Год журнала: 2025, Номер unknown

Опубликована: Апрель 19, 2025

1 Summary Prosthetic limbs lack proprioceptive feedback, which is essential for complex movements. Intracortical mi-crostimulation (ICMS) elicits sensory perceptions that could serve as an artificial signal. However, movements guided by ICMS are slower and less accurate than those with natural sensation. Here, we developed a freely-moving mouse behavioral task to improve encoding of Mice implanted 16-channel microwire arrays in primary somatosensory cortex were trained navigate targets upon the floor custom training cage. Target location was encoded visual and/or feedback. quickly learned use signal locate invisible targets, achieving 75% proficiency on ICMS-only trials first three sessions testing. Furthermore, performance multimodal significantly exceeded unimodal performance, demonstrating animals integrated vision This protocol can be applied efficiently develop test algorithms encode proprioception neural prostheses.

Язык: Английский

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