The medial prefrontal cortex of the brain may be heavily involved in the processes of self-evaluation in humans and body size may play a dominant role in schematic representations of self-worth for many women, according to a study published in the May edition of psychological journal Personality and Individual Differences.
Lead author Mark Allen, PhD, of the psychology department and neuroscience center at Brigham Young University in Provo, Utah, and colleagues said that recent functional imaging studies, as well as behavioral evidence suggests that there are significant differences in sensitivity both to social norms and information about one’s own body, particularly as it pertains to assessments of self-worth for men and women.
“Because these observed sex differences are hypothesized to arise from differences in cognitive representations of the self, brain activation differences in the medial prefrontal cortex might likewise be expected while men and women process information about body image,” said Allen.
For their study, the researchers utilized functional MRI to observe brain activation differences in the medial prefrontal cortex while the study participants were exposed to images of gender-matched bodies of either an overweight body type or a thin body type. Ten females and nine males were selected for inclusion in the research.
The authors wrote that while viewing these images, participants were instructed to make evaluations of their own bodies in relation to the images displayed. Significant medial prefrontal cortex activity within-group contrasts were observed for women only, and higher levels of activation were noted for overweight images compared to thin images. However, men showed no significant medial prefrontal cortex activity while processing either type of image.
“These results are consistent with cognitive models of self-representation, particularly those developed within social and cultural theoretical frameworks, where body size is hypothesized to play a dominant role in schematic representations of self-worth for many women,” explained the authors, who went on to say that the women in the study had no history of eating disorders and generally projected attitudes suggesting indifference regarding body image.
"Many women learn that bodily appearance and thinness constitute what is important about them, and their brain responding reflects that," concluded the authors, noting that this notion may put certain individuals at greater risk for eating and/or mood disorders.