Brain Region Tracking Food Preferences Could Steer People's Food Choices

Specific brain region which monitors food preferences as they change across thirsty and quenched states has been discovered by researchers. By targeting neurons in a specific part of the brain, they could shift food choice preferences from a more desired reward (think: chocolate cake) to a less tasty one (think: stale bread). The findings of the study are published in the journal Science Advances// This study is built upon the same team's discovery two years ago that neural activity in this brain region called the ventral pallidum is related to the preference for different food options.

By working with rats, the researchers demonstrated that this same area of the brain is tracking and updating food preferences in ways that shifted as physiological states progressed from extremely thirsty to happily quenched.

"Your brain has to weigh different probable outcomes or options to make good decisions that are required for survival," stated Patricia Janak, senior author and Bloomberg Distinguished Professor of Psychological and Brain Sciences and Neuroscience at Johns Hopkins. "We knew the ventral pallidum is involved in that process. Exactly how the neurons there perform, that was still a bit of a mystery, particularly in real-time when the best decision for you to make right now can change based on your state."

David Ottenheimer, lead author and a former Johns Hopkins doctoral student who is now at the University of Washington, stated he devised the research to discover how the neurons in the ventral pallidum related to the food decisions subjects made choice shifted due to changes in physiological state.

Researchers gave thirsty rats two options to choose from by selecting one of two levers to study the question. One lever provided plain water, the other a well-liked sugar water.

"At the start, they picked the water when they were thirsty," Ottenheimer stated. "At the end of the test, when they were no longer thirsty, they picked the sugar water, which tastes sweeter."

At the same time, the team monitored the brain activity and found that the neurons reflected the rats' choices for each reward.

"We saw that the neural activity when tasting the sucrose gradually increased over time while the neural activity when tasting the water decreased, which gave us proof that the brain signal is closely related to the change in choice as the subjects became less thirsty and were less interested in the water," Ottenheimer stated.

Notably, in a separate test, the researchers could artificially manipulate the ventral pallidum neurons to force a shift in the choice from the more desired sugar water to a less desirable flavor.

"We hypothesize that the ventral pallidum neurons that are tracing our choices may actually be involved in developing the choices we make when faced with food decisions," Ottenheimer said. "In the future, ventral pallidum may be a good therapeutic target to modify our decision-making processes."

"These same circuits are accountable for decisions made in addiction," Janak stated. "So the data we gain here can help in understanding how we prioritize drugs over other rewards"



Source-Medindia