In obese vs. thin individuals, brain glucose metabolism appears to be much higher in the brain’s striatal regions — areas associated with reward processing, according to researchers at the University of Turku and Aalto University.
Furthermore, an obese person’s reward system seems to respond more vigorously to food pictures, whereas their responses in the frontal cortical regions involved in cognitive function appear lessened.
Since the central nervous system is highly involved in the processing of hunger signals and food intake control, researchers suggest that the cause of obesity might be rooted in the brain. For the study, researchers used various brain imaging methods to measure the involved brain circuits in morbidly obese individuals as well as in lean controls.
Brain glucose metabolism was measured with positron emission tomography during conditions in which the participant’s body was satiated in terms of insulin signaling. Brain responses to food pictures were observed with functional magnetic resonance imaging.
“The results suggest that obese individuals’ brains might constantly generate signals that promote eating even when the body would not require additional energy uptake,” says adjunct professor Lauri Nummenmaa from the University of Turku.
“The results highlight the role of the brain in obesity and weight gaining. The results have major implications on the current models of obesity, but also on development of pharmacological and psychological treatments of obesity,” Nummenmaa says.
Source: Academy of Finland