Moving beyond belief: A narrative review of potential biomarkers for transcutaneous vagus nerve stimulation

Psychophysiology, Год журнала: 2020, Номер 57(6)

Опубликована: Март 23, 2020

Abstract Transcutaneous vagus nerve stimulation (tVNS) is a non‐invasive neurostimulation technique that currently being tested as potential treatment for myriad of neurological and psychiatric disorders. However, the working mechanisms underlying tVNS are poorly understood it remains unclear whether activates every participant. Finding biological marker imperative, can help guide research on clinical applications inform researchers optimal sites parameters to further optimize efficacy. In this narrative review, we discuss five biomarkers review available evidence these markers both invasive tVNS. While some hold promise from theoretical perspective, none provide clear definitive indications increases vagal activity or augments in locus coeruleus‐noradrenaline network. We conclude by providing several recommendations how tackle challenges opportunities when researching effects

Язык: Английский

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Local cortical desynchronization and pupil-linked arousal differentially shape brain states for optimal sensory performance

eLife, Год журнала: 2019, Номер 8

Опубликована: Дек. 10, 2019

Instantaneous brain states have consequences for our sensation, perception, and behaviour. Fluctuations in arousal neural desynchronization likely pose perceptually relevant states. However, their relationship relative impact on perception is unclear. We here show that, at the single-trial level humans, local sensory cortex (expressed as time-series entropy) versus pupil-linked differentially perceptual processing. While we recorded electroencephalography (EEG) pupillometry data, stimuli of a demanding auditory discrimination task were presented into high or low via real-time closed-loop setup. Desynchronization distinctly influenced stimulus-evoked activity shaped behaviour displaying an inverted u-shaped relationship: States intermediate elicited minimal response bias fastest responses, while gave rise to highest sensitivity. Our results speak model which independent global jointly optimise processing performance.

Язык: Английский

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Humans strategically shift decision bias by flexibly adjusting sensory evidence accumulation

eLife, Год журнала: 2019, Номер 8

Опубликована: Фев. 6, 2019

Decision bias is traditionally conceptualized as an internal reference against which sensory evidence compared. Instead, we show that individuals implement decision by shifting the rate of accumulation toward a bound. Participants performed target detection task while recorded EEG. We experimentally manipulated participants' criterion for reporting targets using different stimulus-response reward contingencies, inducing either liberal or conservative bias. Drift diffusion modeling revealed strategy biased target-present choices. Moreover, resulted in stronger midfrontal pre-stimulus 2-6 Hz (theta) power and suppression 8-12 (alpha) posterior cortex. Alpha turn was linked to output activity visual cortex, expressed through 59-100 (gamma) power. These findings observers can intentionally control cortical excitability strategically bound maximizes reward.

Язык: Английский

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Pupil-linked phasic arousal predicts a reduction of choice bias across species and decision domains

eLife, Год журнала: 2020, Номер 9

Опубликована: Июнь 16, 2020

Decisions are often made by accumulating ambiguous evidence over time. The brain’s arousal systems activated during such decisions. In previous work in humans, we found that evoked responses of decisions reported rapid dilations the pupil and track a suppression biases accumulation decision-relevant (de Gee et al., 2017). Here, show this arousal-related decision bias acts on both conservative liberal biases, generalizes from humans to mice, perceptual memory-based challenging sound-detection tasks, impact spontaneous or experimentally induced choice was reduced under high phasic arousal. Similar occurred when drawn memory. All these behavioral effects were explained biases. Our results point general principle interplay between decision-making.

Язык: Английский

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Statistical context dictates the relationship between feedback-related EEG signals and learning

eLife, Год журнала: 2019, Номер 8

Опубликована: Авг. 21, 2019

Learning should be adjusted according to the surprise associated with observed outcomes but calibrated statistical context. For example, when occasional changepoints are expected, surprising weighted heavily speed learning. In contrast, uninformative outliers expected occur occasionally, less influential. Here we dissociate from degree which they demand learning using a predictive inference task and computational modeling. We show that P300, stimulus-locked electrophysiological response previously adjustments in behavior, does so conditionally on source of surprise. Larger P300 signals predicted greater changing context, context where was indicative one-off outlier (oddball). Our results suggest provides signal is interpreted by downstream processes differentially order appropriately calibrate across complex environments.

Язык: Английский

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