A recent study has identified a potential reason why some individuals struggle to stop eating when full, leading to obesity. The research uncovered a structural link between two specific regions of the brain that play a role in regulating feeding behavior. These regions are associated with the sense of smell and behavior motivation. According to the findings, individuals with weaker connections between these brain regions have a higher Body Mass Index (BMI).A recent study in the field of medicine has identified a potential explanation for the link between brain function and feeding behavior. Researchers have uncovered a structural connection between two specific areas of the brain, which are responsible for processing scent and regulating motivation. According to scientists at Northwestern University, individuals with a weaker connection between these regions tend to have a higher Body Mass Index (BMI).
The study revealed a link between the olfactory tubercle, a region of the brain associated with scent perception and the brain’s reward system, and the periaqueductal gray (PAG), a midbrain area involved in motivated behavior. This finding suggests that the strength of the connection between these brain regions may play a role in an individual’s BMI.The study, which will be published on May 16 in the Journal of Neuroscience, found that negative feelings such as pain and threat could potentially suppress eating. Previous research at Northwestern University revealed that the smell of food is more appealing when hungry, but less so when full. This suggests that odors play a crucial role in guiding our eating behaviors, and our sense of smell is influenced by our level of hunger. Scientists have not yet fully understood this connection.Investigating the neural basis of how the sense of smell influences our eating habits, the study uncovered some interesting findings. The lead author, Guangyu Zhou, a research assistant professor of neurology at Northwestern University Feinberg School of Medicine, pointed out that the desire to eat is linked to the appetizing nature of food smells. Hungry individuals tend to perceive food odors as more pleasant compared to when they are full. However, disruptions in the brain circuits responsible for regulating this behavior can result in confusion of these signals, leading to the rewarding perception of food even when one is already satiated. This confusion could potentially contribute to an increase in BMI. The study found evidence that the structural connection between these circuits could play a role in this process.Brain regions that are weaker are associated with higher BMI, according to a study. The researchers suggest that healthy brain networks could regulate eating behavior by sending signals that eating doesn’t feel good anymore when full. This could act as a switch in the brain that turns off the desire to eat. However, people with weak or disrupted circuits connecting these areas may not receive these signals, leading them to continue eating even when not hungry. This understanding is important in managing eating behavior.Understanding how these fundamental processes operate in the brain is an essential first step to future research that could result in treatments for overeating,” explained Christina Zelano, senior author and associate professor of neurology at Feinberg.
Study Methodology
This research utilized MRI brain data — neurological imaging — from the Human Connectome Project, a large multi-center NIH project aimed at constructing a network map of the human brain.
Zhou from Northwestern University discovered associations with BMI in the circuit between the olfactory tubercle and the midbrain region, the periaqueductal gray, for the first time ever.Zhou also used imaging to map the strength of the circuit in the olfactory tubercle in humans. The findings were then replicated in a smaller MRI brain dataset collected in their lab at Northwestern.
“Future studies will be needed to uncover the exact mechanisms in the brain that regulate eating behavior,” Zelano said.
The research reported in this press release was supported by the National Institute on Deafness and Other Communication Diseases grants R01-DC-016364, R01-DC-018539, R01-DC-015426 and the Intramural Research Program at the National Institute on Drug Abuse grant ZIA DA000642, all of the National Institutes of Health.
