Low-threshold, high-resolution, chronically stable intracortical microstimulation by ultraflexible electrodes

Cell Reports, Journal Year: 2023, Volume and Issue: 42(6), P. 112554 - 112554

Published: May 24, 2023

Intracortical microstimulation (ICMS) enables applications ranging from neuroprosthetics to causal circuit manipulations. However, the resolution, efficacy, and chronic stability of neuromodulation are often compromised by adverse tissue responses indwelling electrodes. Here we engineer ultraflexible stim-nanoelectronic threads (StimNETs) demonstrate low activation threshold, high chronically stable ICMS in awake, behaving mouse models. In vivo two-photon imaging reveals that StimNETs remain seamlessly integrated with nervous throughout stimulation periods elicit stable, focal neuronal at currents 2 μA. Importantly, evoke longitudinally behavioral for over 8 months a markedly charge injection 0.25 nC/phase. Quantified histological analyses show induces no degeneration or glial scarring. These results suggest tissue-integrated electrodes provide path robust, long-lasting, spatially selective currents, which lessens risk damage exacerbation off-target side effects.

Language: Английский

---

Consensus Paper: Experimental Neurostimulation of the Cerebellum

The Cerebellum, Journal Year: 2019, Volume and Issue: 18(6), P. 1064 - 1097

Published: June 4, 2019

The cerebellum is best known for its role in controlling motor behaviors. However, recent work supports the view that it also influences non-motor contribution of towards different brain functions underscored by involvement a diverse and increasing number neurological neuropsychiatric conditions including ataxia, dystonia, essential tremor, Parkinson's disease (PD), epilepsy, stroke, multiple sclerosis, autism spectrum disorders, dyslexia, attention deficit hyperactivity disorder (ADHD), schizophrenia. Although there are no cures these conditions, cerebellar stimulation quickly gaining symptomatic alleviation, as circuitry has arisen promising target invasive non-invasive neuromodulation. This consensus paper brings together experts from fields neurophysiology, neurology, neurosurgery to discuss efforts using therapeutic intervention. We report on most advanced techniques manipulating circuits humans animal models define key hurdles questions moving forward.

Language: Английский

---

Tissue Response to Neural Implants: The Use of Model Systems Toward New Design Solutions of Implantable Microelectrodes

Frontiers in Neuroscience, Journal Year: 2019, Volume and Issue: 13

Published: July 5, 2019

The development of implantable neuroelectrodes is advancing rapidly as these tools are becoming increasingly ubiquitous in clinical practice, especially for the treatment traumatic and neurodegenerative disorders. Electrodes have been exploited a wide number neural interface devices, such deep brain stimulation, which one most successful therapies with proven efficacy diseases like Parkinson or epilepsy. However, main caveats related to application electrodes nervous tissue response at injury site, characterized by cascade inflammatory events, culminate chronic inflammation, and, turn, result failure implant over extended periods time. To overcome current limitations widespread macroelectrode based systems, new design strategies innovative materials superior biocompatibility characteristics currently being investigated. This review describes state art vitro, ex vivo models available study microelectrodes. We particularly highlight increased complexity that closely mimic scenarios can serve promising alternatives animal studies investigation microelectrodes tissues. Additionally, we also express our view on impact progress field engineering research.

Language: Английский

---

Intravital imaging of mouse embryos

Science, Journal Year: 2020, Volume and Issue: 368(6487), P. 181 - 186

Published: April 9, 2020

A window to the embryo Mammalian embryonic development is a complex process, continuously changing in space and time. Q. Huang et al. designed an abdominal image mouse embryos utero from day 9.5 birth. Using this technique, they visualized dynamic activities during organ formation, including neurotransmission cell division brain, autophagy retina, viral gene delivery, placental drug transfer. They also tracked diverging fates of human neural crest cells interspecies chimeras. Science , issue p. 181

Language: Английский

---

Perception of microstimulation frequency in human somatosensory cortex

eLife, Journal Year: 2021, Volume and Issue: 10

Published: July 27, 2021

Microstimulation in the somatosensory cortex can evoke artificial tactile percepts and be incorporated into bidirectional brain–computer interfaces (BCIs) to restore function after injury or disease. However, little is known about how stimulation parameters themselves affect perception. Here, we stimulated through microelectrode arrays implanted of two human participants with cervical spinal cord varied stimulus amplitude, frequency, train duration. Increasing amplitude duration increased perceived intensity on all tested electrodes. Surprisingly, found that increasing frequency evoked more intense some electrodes but less-intense other These different frequency–intensity relationships were divided three groups, which also distinct percept qualities at frequencies. Neighboring electrode sites likely belong same group. results support idea directly controls perception these may related organization cortex, will facilitate principled development strategies for BCIs.

Language: Английский

---

The science and engineering behind sensitized brain-controlled bionic hands

Physiological Reviews, Journal Year: 2021, Volume and Issue: 102(2), P. 551 - 604

Published: Sept. 20, 2021

Advances in our understanding of brain function, along with the development neural interfaces that allow for monitoring and activation neurons, have paved way brain-machine (BMIs), which harness signals to reanimate limbs via electrical muscles or control extracorporeal devices, thereby bypassing senses altogether. BMIs consist reading out motor intent from neuronal responses monitored regions executing intended movements bionic limbs, reanimated exoskeletons. also restoration sense touch by electrically activating neurons somatosensory brain, evoking vivid tactile sensations conveying feedback about object interactions. In this review, we discuss mechanisms somatosensation able-bodied individuals describe approaches use as movement activate residual sensory pathways restore touch. Although focus review is on intracortical approaches, alternative signal sources noninvasive strategies restoration.

Language: Английский

---

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

Brain stimulation, Journal Year: 2024, Volume and Issue: 17(2), P. 365 - 381

Published: March 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.

Language: Английский

---

Revealing Spatial and Temporal Patterns of Cell Death, Glial Proliferation, and Blood-Brain Barrier Dysfunction Around Implanted Intracortical Neural Interfaces

Frontiers in Neuroscience, Journal Year: 2019, Volume and Issue: 13

Published: May 28, 2019

Improving the long-term performance of neural electrode interfaces requires overcoming severe biological reactions such as neuronal cell death, glial activation, and vascular damage in presence implanted intracortical devices. Past studies traditionally observe neurons, microglia, astrocytes, blood-brain barrier disruption around inserted microelectrode arrays. However, analysis these factors alone yields poor correlation between tissue inflammation device performance. Additionally, often overlook significant responses that can occur during acute implantation injury. The current study employs additional histological markers provide novel information about neglected components—oligodendrocytes their myelin structures, oligodendrocyte precursor cells, barrier-associated pericytes—during foreign body response to devices at 1, 3, 7, 28 days post-insertion. Our results reveal unique temporal spatial patterns loss, axonal reorganization, reactivity, pericyte deficiency both acutely chronically Furthermore, probing for immunohistochemical highlight mechanisms death or proliferation differentiation have provided new insight into inflammatory dynamics

Language: Английский

---

Neural and electromyography PEDOT electrodes for invasive stimulation and recording

Journal of Materials Chemistry C, Journal Year: 2021, Volume and Issue: 9(23), P. 7243 - 7263

Published: Jan. 1, 2021

The conducting polymer poly(3,4-ethylenedioxythiophene) (PEDOT) is increasingly used for implantable electrodes. This review discusses the key aspects of PEDOT-based electrodes neural recording, stimulation and electromyography.

Language: Английский

---

Electrode Materials for Chronic Electrical Microstimulation

Advanced Healthcare Materials, Journal Year: 2021, Volume and Issue: 10(12)

Published: May 24, 2021

Electrical microstimulation has enabled partial restoration of vision, hearing, movement, somatosensation, as well improving organ functions by electrically modulating neural activities. However, chronic is faced with numerous challenges. The implantation an electrode array into the tissue triggers inflammatory response, which can be exacerbated delivery electrical currents. Meanwhile, prolonged stimulation may lead to material degradation., accelerated hostile environment. Both degradation and adverse reactions compromise performance over time. For stable stimulation, ideal microelectrode must present 1) high charge injection limit, efficiently deliver without exceeding safety limits for both electrodes, 2) small size, gain spatial selectivity, 3) excellent biocompatibility that ensures health immediately next device, 4) in vivo electrochemical properties application period. In this review, challenges are described detail. To aid scientists interested research, vitro testing methods introduced assessing functionality longevity a detailed overview recent advances research device fabrication provided.

Language: Английский

---