Pupil-Indexed Noninvasive Neuromodulation

Existing evidence supports the use of VNS to enhance the effects of traditional therapy on impairments due to neurological injury. It is known that the vagus nerve forms contacts with neuromodulatory nuclei in the brainstem that release of chemicals shown to be critically involved in attentional control and memory formation. It is also known that the auricular branch of the vagus nerve innervates portions of the external ear providing a possible means to engage similar neural pathways noninvasively via transcutaneous auricular vagus nerve stimulation (taVNS). Recent work from the PI's laboratory shows that electrical current applied to landmarks on the external ear elicits transient effects on pupil dilation, an established physiological index of brain states that support learning. Given the ability to engage the biomarker, the investigators aim to further investigate physiological mechanisms modulated by taVNS and possible effects on learning.