Brain activation to high-calorie food images in healthy normal weight and obese children: A fMRI study

Authors: SAMARA, AMJAD - University Arkansas For Medical Sciences (UAMS); LI, XUEHUA - University Arkansas For Medical Sciences (UAMS); PIVIK, R T - University Arkansas For Medical Sciences (UAMS); Badger, Thomas; OU, XIAWEI - University Arkansas For Medical Sciences (UAMS)

Submitted to: BMC Obesity
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 8/20/2018
Publication Date: 12/3/2018
Citation: Samara, A., Li, X., Pivik, R., Badger, T.M., Ou, X. 2018. Brain activation to high-calorie food images in healthy normal weight and obese children: A fMRI study. BMC Obesity. 5:31. https://doi.org/10.1186/s40608-018-0209-1.
DOI: https://doi.org/10.1186/s40608-018-0209-1

Interpretive Summary: Childhood obesity is a major public health concern. Among various factors, an unhealthy eating pattern is one of the major contributors. Complex food behaviors leading to excess body weight may have their origins in distinct brain functional differences in obese compared to non-obese children. To examine this question, we compared how brains of 8-10 yr old normal weight and overweight children respond to food stimuli. This is possible using modern brain imaging technologies. For example, "functional magnetic resonance imaging (fMRI)" is an advanced brain imaging technique that measures brain activity associated with changes in blood flow in different brain regions. It is been widely used to study brain activity during certain tasks, like viewing food images. In our study, we determined brain activation differences in response to viewing high-calorie food images. The results indicate that select brain regions differ between normal weight and obese children. This indicates that the two groups think about high-calorie foods in different ways. To explain the activation patterns we observed, and based on our previous knowledge about the functions of the involved brain regions, we suggested that normal-weight children may think about food healthiness more than obese children when they both view same food images. However, further research is needed to correlate these neuroimaging results with behavioral assessments to evaluate children's mindset regarding healthy/unhealthy food choices. As this information develops, it will help bridge the gap in our understanding of the link between obesity and the brain. From a public health point of view, this will help in the development of early intervention strategies related to healthy food behaviors, to help deal with childhood obesity and avoid related undesirable health consequences.

Technical Abstract: Understanding how normal weight and obese young children process high-calorie food stimuli may provide information relevant to the neurobiology of eating behavior contributing to childhood obesity. In this study, we used fMRI to evaluate whether brain activation to high-calorie food images differs between normal weight and obese young children. Brain activation maps in response to high-calorie food images and non-food images for 22 healthy, 8–10-years-old children (N = 11/11 for normal weight/obese respectively) were generated and compared between groups. When comparing brain activation differences in response to viewing high-calorie food versus non-food images between normal weight and obese children, group differences were observed in areas related to memory and cognitive control. Specifically, normal weight children showed higher activation of posterior parahippocampal gyri (PPHG) and dorsomedial prefrontal cortex (DMPFC). Further ROI analyses indicated higher activation strength (Z scores) in the right PPHG (p = 0.01) and higher activation strength (p < 0.001) as well as a larger activation area (p = 0.02) in the DMPFC in normal weight than obese children. Normal weight and obese children process high-calorie food stimuli differently even from a young age. Normal weight children exhibit increased brain activation in regions associated with memory and cognitive control when viewing high-calorie food images.