New research published in the October 2015 issue of the journal Brain and Cognition found that the brain undergoes dramatic neurophysiological changes in response to food images that exacerbate physiological hunger. According to the study, “external food cues, such as the sight of appetizing food, can evoke a desire to eat, even in the absence of hunger.”
Study authors conducted a meta-analysis of neuroimaging of more than 1,500 subjects to assess the neural response to visual cues as related to their current weight and satiety level. Obese individuals were shown to be more responsive to food cues when in a satiated state than healthy weight individuals. When hungry, neural activation of reward centers were observed in obese individuals while the areas of the brain associated with cognitive control were activated in healthy-weight individuals. This branch of the study suggests that the weight of the viewer influences the brain’s response to food images.