Brain stimulation increases motivation to work for food

Electrical stimulation of the brain by the vagus nerve increases the motivation to work to feed, according to recent findings of a research group of the University of Tübingen. These findings, presented at the Society's annual meeting for the study of ingested behavior, this week in Utrecht, the Netherlands, demonstrate a new method for changing the motivation to obtain food.

"A vigorous job is expensive and needs to be recovered by energy intake, so it's essential for us to know when the effort is worth it." The vagus nerve helps set the tone for actions by signaling, for example, if energy is immediately available this action or not, "says Dr. Nils B. Kroemer, Senior Research Scientist and Junior Group Leader of the Motivational Neuroscience Laboratory, of the University of Ottawa. action and desire of the university (neuroMADLAB). "We knew that vagus nerve stimulation altered dopamine levels in animals and that chronic stimulation improved depressive symptoms in humans, but we do not did not know if this could significantly improve motivation. We discovered that this technique could provide an indispensable technique for rapidly changing the benefits. "Related behavior such as eating".

The researchers invited 81 hungry participants to their laboratory twice. Everyone saw themselves offering a delicious breakfast, but there was a catch. Participants had to work hard to earn reward points that could be "traded" for their favorite cereals. In one of the two sessions, participants completed the task while receiving electrical stimulation of the vagus nerve; during the other session, they received placebo stimulation. The results showed that the stimulation increased the vigor with which the participants exerted an effort to obtain the rewards involved in relation to the control condition.

"This ambitious experiment is one of the first to study motivational changes during acute stimulation of the vagus nerve," said Monja P. Neuser, Ph.D. student at neuroMADLAB and senior author of the study. "Motivational effects induced by stimulation are very promising and we encourage to deepen the exact neural mechanisms.We believe that stimulation increases dopamine levels in the brain, which is known to increase vigor."

By using competing functional neuroimaging, neuroMADLAB researchers will continue their research into the possibilities of administering non-invasive vagus nerve stimulation to maximize the benefits. The researchers plan to apply this technique to people suffering from Anhedonia – a lack of desire to participate in normally enjoyable activities such as eating – to determine whether it increases their motivation to search for and consume food.

More information:
Quote of the research: Go ahead: tVNS increases the dynamism of food rewards, presented in July 2019 to the Society for the Study of Ingested Behavior, Utrecht, NL

Provided by
Society for the study of ingested behavior