Non-invasive cervical vagus nerve stimulation effects on reaction time and valence image anticipation response

Brain stimulation, Journal Year: 2022, Volume and Issue: 15(4), P. 946 - 956

Published: June 20, 2022

BackgroundNorepinephrine (NE) driven noninvasive vagus nerve stimulation (nVNS), which improves attention and reduces reaction time, augments learning. Equally important, endogenous NE mediated arousal is highly dependent on the valence (positive or negative) of exogenous stimulus. But to date, no study has measured specific effects nVNS both functional magnetic resonance imaging (fMRI) anticipation task response time in healthy individuals. Therefore, aim this pilot was assess whether vs sham modulates cortical a normative sample.MethodsParticipants received right sided transcutaneous cervical (N = 12) during 3T fMRI scan. Subjects first performed continuous performance (CPT) then cued images positively negatively valenced events fMRI. Reaction times cues Blood oxygen level (BOLD) were examined over phase identify nVNS/sham time.ResultsnVNS reduced for all image trials. With task, we observed valence-specific effect; increased responsivity with negative decreased positive valence, whereas showed an inverse response.ConclusionsnVNS linked task. In tandem, consistently enhanced diminished images, suggesting neurotransmitter signaling may contribute.

Language: Английский

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300 Hz transcutaneous auricular vagus nerve stimulation (taVNS) impacts pupil size nonlinearly as a function of intensity

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

Published: April 25, 2024

Abstract Transcutaneous auricular vagus nerve stimulation (taVNS) is a neuromodulatory technique that may have numerous potential health and human performance benefits. However, optimal parameters for maximizing taVNS efficacy are unknown. Progress impeded by disagreement on the identification of biomarker reliably indexes activation systems targeted taVNS, including locus coeruleus-norepinephrine (LC-NE) system. Pupil size varies with LC-NE activity one has shown inconsistent sensitivity to in prior studies. The present study examined relationship between pupil using promising behavioral effects studies but received comparatively little attention. Participants 30-second trains 50 μs pulses delivered below perceptual threshold at 300 Hz left external acoustic meatus (EAM) while was recorded during pupillary light reflex task. Analysis generalized additive mixed modelling (GAMM) revealed nonlinear intensity diameter. Active increased participants who 2 approximately 4.8 mA, not higher (up 8.1 mA). In addition, persisted subsequent blocks, mitigating decreases over course These findings suggest activates system when applied EAM, its be counteracted intensities.

Language: Английский

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The impact of age and Alzheimer’s disease on locus coeruleus mediated neuromodulation of neural circuits and goal-directed behavior

Published: Feb. 6, 2023

Neuromodulators affect cognition and behavior via their actions on brain wide neural networks. The locus coeruleus norepinephrine (LC-NE) system is one of the brain’s major neuromodulatory systems. Aging neurological diseases lead to changes in structure that impact normal functioning networks Although precise nature this impact, its diagnosis quantification remain a challenge, recent studies humans animal models have started reveal details about effects intrinsic neuromodulators behavior. These findings are beginning suggest how systems neuroscience approaches might help develop new tests supplement range established clinical assays for testing cognitive deficits due aging Alzheimer’s disease. Here, I will review what we know perform computations driving perception action these affected by activation LC-NE system. examine known disease related resulting action. discuss relationships between pupil size, recently explored with precision models. how, when combined perceptual or tests, provide basis exploring use pupillometry as non-invasive assay age- disease-related decline neuromodulatoryfunction.

Language: Английский

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Non‐invasive vagus nerve stimulation and the motivation to work for rewards: A replication of Neuser et al. (2020, Nature Communications)

Psychophysiology, Journal Year: 2023, Volume and Issue: 61(4)

Published: Nov. 9, 2023

Abstract The vagus nerve is thought to be involved in the allostatic regulation of motivation and energy metabolism via gut‐brain interactions. A recent study by Neuser colleagues (2020) provided novel evidence for this process humans, reporting a positive effect transcutaneous auricular stimulation (taVNS) on invigoration reward‐seeking behaviors, especially food rewards. We conducted an independent direct replication et al. (2020), assess robustness their findings. Following original study, we used single‐blind, sham‐controlled, randomized cross‐over design. applied left‐sided taVNS healthy human volunteers ( n = 40), while they performed effort allocation task which had work monetary was purely confirmatory that it strictly followed analysis plans scripts Although, line with al., found strong effects variables maintenance, failed replicate key finding: did not increase strength p .62); data were five times more likely (BF 10 0.19) under null hypothesis. also substantial against maintenance .50; BF 0.20). Our results provide idea boosts motivational drive highlights need replications influential studies.

Language: Английский

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Tonic and phasic transcutaneous auricular vagus nerve stimulation both evoke rapid and transient pupil dilation

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

Published: Sept. 22, 2023

Abstract Background Transcutaneous auricular vagus nerve stimulation (tVNS or taVNS) is a non-invasive method of electrical the afferent pathway nerve, suggested to drive changes in putative physiological markers noradrenergic activity, including pupil dilation. Objective However, it unknown whether different taVNS modes can map onto phasic and tonic activity. The effects on dilation humans are inconsistent, largely due differences protocols. Here, we attempted address these issues. Methods We investigated under (1 s) (30 taVNS, pre-registered, single-blind, sham-controlled, within-subject cross-over design, absence behavioural task. Results Phasic induced rapid increase size over baseline, significantly greater than sham stimulation, which rapidly declined after offset. Tonic similarly (and larger sham) returning baseline within 5 s, despite ongoing stimulation. Thus, both active closely resembled effect. There were no size, sustained size. Conclusions These results suggest that phasic- tonic-like standard parameters may modulate primarily mode as indexed by evoked dilation, above somatosensory effects. This result sheds light temporal profile with implications for their applicability further research.

Language: Английский

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