TY  - JOUR
AU  - Ludwig, Mareike
AU  - Pereira, Calida
AU  - Keute, Marius
AU  - Düzel, Emrah
AU  - Betts, Matthew J
AU  - Hämmerer, Dorothea
TI  - Evaluating phasic transcutaneous vagus nerve stimulation (taVNS) with pupil dilation: the importance of stimulation intensity and sensory perception.
JO  - Scientific reports
VL  - 14
IS  - 1
SN  - 2045-2322
CY  - [London]
PB  - Macmillan Publishers Limited, part of Springer Nature
M1  - DZNE-2024-01236
SP  - 24391
PY  - 2024
AB  - The efficacy of transcutaneous auricular vagus nerve stimulation (taVNS) as a non-invasive method to modulate physiological markers of noradrenergic activity of the Locus Coeruleus (LC), such as pupil dilation, is increasingly more discussed. However, taVNS studies show high heterogeneity of stimulation effects. Therefore, a taVNS setup was established here to test different frequencies (10 Hz and 25 Hz) and intensities (3 mA and 5 mA) during phasic stimulation (3 s) with time-synchronous recording of pupil dilation in younger adults. Specifically, phasic real taVNS and higher intensity led to increased pupil dilation, which is consistent with phasic invasive VNS studies in animals. The results also suggest that the influence of intensity on pupil dilation may be stronger than that of frequency. However, there was an attenuation of taVNS-induced pupil dilation when differences in perception of sensations were considered. Specifically, pupil dilation during phasic stimulation increased with perceived stimulation intensity. The extent to which the effect of taVNS induces pupil dilation and the involvement of sensory perception in the stimulation process are discussed here and require more extensive research. Additionally, it is crucial to strive for comparable stimulation sensations during systematic parameter testing in order to investigate possible effects of phasic taVNS on pupil dilation in more detail.
KW  - Humans
KW  - Vagus Nerve Stimulation: methods
KW  - Pupil: physiology
KW  - Male
KW  - Adult
KW  - Female
KW  - Transcutaneous Electric Nerve Stimulation: methods
KW  - Young Adult
KW  - Vagus Nerve: physiology
KW  - Locus Coeruleus: physiology
LB  - PUB:(DE-HGF)16
C6  - pmid:39420188
C2  - pmc:PMC11487125
DO  - DOI:10.1038/s41598-024-72179-4
UR  - https://pub.dzne.de/record/272818
ER  -