Non-invasive vagus nerve stimulation in a hungry state decreases heart rate variability
Büyükgüdük, ilkim | Yanık, Hüseyin | Yılmaz, Dilan Dneiz | Yar, Berçem | Değirmenci, Evren | Dal, Uğur | Geraldine Veldhuizen, Maria
Vagus nerve signals from the gut to brain carry information about nutrients and drive food reward. Such signals are disrupted by consuming large amounts of high-calorie foods, necessitating greater food intake to elicit a similar neural response. Non‐invasive vagus nerve stimulation (nVNS) via a branch innervating the ear is a candidate treatment for obesity in humans. There is disagreement on the optimal location of nVNS in the ear for experimental and clinical studies. There are also no studies comparing nVNS in hungry and post-prandial states. We aimed to compare ear position(s) for nVNS and explore the effects of nVNS during hungry and post-prandial states on proxies for autonomic outflow (heart-rate variability) and efferent metabolism (gastric wave frequency and resting energy expend...
CAN NON-INVASIVE VAGUS NERVE STIMULATION CONDITION PREFERENCE FOR NEW FLAVORS PAIRED WITH LOW-FAT FOODS?
Büyükgüdük, İlkim | Geraldine Veldhuizen, Maria | Yılmaz, Dilan Deniz | Dal, Uğur
Conditioned flavor preference can be formed when a novel flavor is associated with for example palatable taste and/ or with positive post-digestive effects. Recent research on the vagus nerve (VN) using chemogenetic and optogeneti stimulation has shown that vagal gut-brain communication underlies this learning. If VN activity triggers food reward, we predict that non-invasive VN stimulation (nVNS, compared to pseudo-stimulation) will condition liking for new flavors paired with low-fat foods. In order to select flavors for conditioning, 17 participants tasted and rated 10 flavors using the sip and-spit method. The participants rated liking and wanting. Two flavors that are similarly near to neutral in liking were chosen for the conditioning sessions. To induce associative conditioning, we ...