Thalamic feedback shapes brain responses evoked by cortical stimulation in mice and humans

Nature Communications, Journal Year: 2025, Volume and Issue: 16(1)

Published: April 16, 2025

Cortical stimulation with single pulses is a common technique in clinical practice and research. However, we still do not understand the extent to which it engages subcortical circuits that may contribute associated evoked potentials (EPs). Here show cortical generates remarkably similar EPs humans mice, late component similarly modulated by state of targeted cortico-thalamic network. We then optogenetically dissect underlying circuit demonstrating caused thalamic hyperpolarization rebound. The magnitude this correlates bursting frequency synchronicity neurons, subject's behavioral state. A simulation thalamo-cortical highlights both intrinsic currents as well GABAergic neurons response profile. conclude pulse cortico-thalamo-cortical largely preserved across different species modalities.

Language: Английский

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A Novel Approach to Implementing Artificial Thalamic Neurons with Ferroelectric Transistors

Advanced Functional Materials, Journal Year: 2025, Volume and Issue: unknown

Published: April 25, 2025

Abstract Artificial thalamic neurons offer significant potential for medical treatment and neuromorphic computing applications. Their implementation with CMOS technology typically requires a large number of transistors capacitors, leading to increased power consumption reduced integration density. This work presents an artificial relay neuron using only five identical ferroelectric Schottky barrier field‐effect (Fe‐SBFETs) based on silicon technology, forming double inverter sensing transistor. The ambipolar switching behavior Fe‐SBFETs not supports both excitatory inhibitory synapses single device but also allows the construction inverters just two transistors. fabricated exhibits leaky integrate‐and‐fire‐or‐burst (LIFB) functionality self‐resetting capabilities. enables generate spikes reset time 10 µs, spike frequency 8.3 kHz, average energy loss 40 pJ −1 . successful is able develop low‐power, compact neural networks relatively high operating frequencies.

Language: Английский

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A model of thalamo-cortical interaction for incremental binding in mental contour-tracing

PLoS Computational Biology, Journal Year: 2025, Volume and Issue: 21(5), P. e1012835 - e1012835

Published: May 8, 2025

Object-basd visual attention marks a key process of mammalian perception. By which mechanisms this is implemented and how it can be interacted with by means attentional control not completely understood yet. Incremental binding mechanism required in demanding scenarios object-based experimentally well investigated. Attention spreads across representation the object labels bound elements constant up-modulation neural activity. The speed incremental was found to dependent on spatial arrangement distracting scene scale invariant giving rise growth-cone hypothesis. In work, we propose dynamical model that provides mechanistic account for these findings. Through simulations, investigate properties demonstrate an spreading tags neurons participate process. They utilize Gestalt eventually show characteristics labeling perceptual items delayed activity enhancement neuronal firing rates. We discuss algorithmic underlying relate our computations. This theoretical investigation encompasses complexity considerations finds only explanatory value terms neurophysiological evidence, but also efficient implementation striving establish normative account. relating connectivity motifs neuroanatomical suggest thalamo-cortical interactions likely candidate flexible realization suggested model. There, pyramidal cells are proposed serve as processors grouping information. Local bottom-up evidence about stimulus features integrated via basal dendritic sites. It combined apical signal consisting contextual information gated task-relevance selection mediated higher-order thalamic representations.

Language: Английский

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A tactile discrimination task to study neuronal dynamics in freely-moving mice

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

Published: Aug. 26, 2024

Abstract Sensory discrimination tasks are valuable tools to study neuronal mechanisms of perception and learning. Most the previously developed for electrophysiological imaging studies in rodents require animals be head-fixed. However, implementing neurophysiological recordings into more ethologically realistic settings with unrestrained has been challenging, especially somatosensory studies. This introduces a tactile task freely moving mice, integrating electrophysiology calcium cellular resolution. In this go/no-go paradigm, mice learn discriminate between different aperture widths within days order forage food rewards on linear platform. We demonstrate that is whisker-dependent reliably differences as small 6 mm. The setup’s versatility enables exploration diverse behavioral aspects, including thresholds, valence-dependent behavior, cognitive flexibility following repeated rule reversals. Rule learning was highly stereotypical, fast reproducible across individual approximately 500 trials attain expert level performance 1000 relearn first reversal. further can conducted same paradigm such multiple read-outs (learning progression, whisker motion, touch, reward licking) synchronized respective data, providing new versatile tool elucidate neural cognition sensory processing.

Language: Английский

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Stimulus contrast modulates burst activity in the lateral geniculate nucleus

Current Research in Neurobiology, Journal Year: 2023, Volume and Issue: 4, P. 100096 - 100096

Published: Jan. 1, 2023

Burst activity is a ubiquitous feature of thalamic neurons and well documented for visual in the lateral geniculate nucleus (LGN). Although bursts are often associated with states drowsiness, they also known to convey information cortex particularly effective evoking cortical responses. The occurrence depends on (1) inactivation gate T-type Ca2+ channels (T-channels), which become de-inactivated following periods increased membrane hyperpolarization, (2) opening T-channel activation gate, has voltage-threshold rate-of-change (δv/δt) requirements. Given time/voltage relationship generation potentials that underlie burst events, it reasonable predict influenced by luminance contrast drifting grating stimuli, null phase higher stimuli greater hyperpolarization followed larger dv/dt than lower stimuli. To determine between stimulus activity, we recorded spiking cat LGN while presenting sine-wave gratings varied contrast. Results show rate, reliability, timing precision significantly compared Additional analysis from simultaneous recordings synaptically connected retinal ganglion cells further reveals dynamics underlying activity. Together, these results support hypothesis biophysical properties state interact influence presumably facilitate thalamocortical communication detection.

Language: Английский

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Current Practice in Using Voltage Imaging to Record Fast Neuronal Activity: Successful Examples from Invertebrate to Mammalian Studies

Biosensors, Journal Year: 2023, Volume and Issue: 13(6), P. 648 - 648

Published: June 13, 2023

The optical imaging of neuronal activity with potentiometric probes has been credited being able to address key questions in neuroscience via the simultaneous recording many neurons. This technique, which was pioneered 50 years ago, allowed researchers study dynamics neural activity, from tiny subthreshold synaptic events axon and dendrites at subcellular level fluctuation field potentials how they spread across large areas brain. Initially, synthetic voltage-sensitive dyes (VSDs) were applied directly brain tissue staining, but recent advances transgenic methods now allow expression genetically encoded voltage indicators (GEVIs), specifically selected neuron types. However, is technically difficult limited by several methodological constraints that determine its applicability a given type experiment. prevalence this method far comparable patch clamp or similar routine research. There are more than twice as studies on VSDs there GEVIs. As can be seen majority papers, most them either ones reviews. neurons simultaneously, thus providing unique information cannot obtained other methods. Different types have their advantages limitations, we focus detail. Here, summarize experience scientific community application try evaluate contribution

Language: Английский

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Optimization of Temporal Coding of Tactile Information in Rat Thalamus by Locus Coeruleus Activation

Biology, Journal Year: 2024, Volume and Issue: 13(2), P. 79 - 79

Published: Jan. 28, 2024

The brainstem noradrenergic nucleus, the locus coeruleus (LC), exerts heavy influences on sensory processing, perception, and cognition through its diffuse projections throughout brain. Previous studies have demonstrated that LC activation modulates response feature selectivity of thalamic relay neurons. However, extent to which temporal coding information in thalamus remains mostly unknown. Here, we found stimulation significantly altered structure responses neurons repeated whisker stimulation. A substantial portion events (i.e., time points where stimulus reliably evoked spikes as evidenced by dramatic elevations firing rate spike density function) were removed during stimulation, but many new emerged. Interestingly, within emerged a higher selectivity, therefore transmit more about tactile stimulus, than events. This suggests optimized improve transmission. We further reconstructed original from population neurons’ corresponding selectivity. As expected, reconstruction was accurate using trains recorded without functionally confirming optimization code. Together, our results LC-NE system optimizes thalamus, presumably allowing for decoding downstream brain structures.

Language: Английский

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Multiple distinct timescales of rapid sensory adapation in the thalamocortical circuit

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

Published: June 6, 2024

Numerous studies have shown that neuronal representations in sensory pathways are far from static but instead strongly shaped by the complex properties of inputs they receive. Adaptation dynamically shapes neural signaling underlies our perception world yet remains poorly understood. We investigated rapid adaptation across timescales hundreds milliseconds to seconds through simultaneous multi-electrode recordings ventro-posteromedial nucleus thalamus (VPm) and layer 4 primary somatosensory cortex (S1) male female anesthetized mice response controlled, persistent whisker stimulation. Observations VPm S1 reveal a degree progresses pathway. Signatures two distinct firing rates both thalamic cortical populations were revealed, also reflected synchrony population thalamocortical synaptic efficacy was measured putatively monosynaptically connected pairs. Controlled optogenetic activation further demonstrated longer timescale observed is likely inherited slow decreases rate synchrony. Despite degraded responses, resulted shift coding strategy favors theoretical discrimination over detection adaptation. Overall, although multiple mechanisms contribute at timescales, support unifying framework on role processing.

Language: Английский

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Alterations of sensory cell activity in the thalamic reticular nucleus by prefrontal cortex activation in anesthetized rats

European Journal of Neuroscience, Journal Year: 2023, Volume and Issue: 58(2), P. 2469 - 2503

Published: June 7, 2023

The thalamic reticular nucleus (TRN), receiving excitatory inputs from nuclei and cortical areas, regulates sensory processing through its inhibitory projections to nuclei. Higher cognitive function has been shown affect this regulation the prefrontal cortex (PFC). present study examined how activation of PFC modulates auditory or visual responses single TRN cells in anesthetized rats, using juxta-cellular recording labelling techniques. Electrical microstimulation medial did not evoke cell activities TRN, but it altered majority (40/43) (19/20) with regard response magnitude, latency and/or burst spiking. Alterations magnitude were bidirectional, either facilitation attenuation, including induction de novo activity nullification response. Response modulation was observed early (onset) recurrent late responses. stimulation, before after response, affected occurred two types projecting first- higher-order Further, somatosensory affected. Facilitation induced at relatively high incidences as compared that sub-threshold intra- cross-modal interplay where attenuation is predominated bidirectional modulation. Highly complex cooperative competitive interactions between top-down influence bottom-up are assumed take place adjust attention perception depending on weights external signals internal demands higher function.

Language: Английский

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Dynamic corticothalamic modulation of the somatosensory thalamocortical circuit during wakefulness

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2023, Volume and Issue: unknown

Published: July 19, 2023

The feedback projections from cortical layer 6 (L6CT) to sensory thalamus have long been implicated in playing a primary role gating signaling but remain poorly understood. To causally elucidate the full range of effects these projections, we targeted silicon probe recordings whisker thalamocortical circuit awake mice selectively expressing Channelrhodopsin-2 L6CT neurons. Through optogenetic manipulation neurons, multi-site electrophysiological recordings, and modeling circuitry, establish neurons as dynamic modulators ongoing spiking ventro-posterior-medial nucleus (VPm), either suppressing or enhancing VPm depending on neurons' firing rate synchrony. Differential across excitatory inhibitory sub-populations point an overall influence excitability that could profound implications for regulating ethologically relevant conditions.

Language: Английский

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