Adolescents with eating disorders have debilitating cognitive disturbances that impact on their social, educational and physical health. One cognitive trait that is found to form core cognitive disturbances in AN is superior working memory (WM). WM is the ability to ruminate on a cognitive strategy while attending to the details of another task, excluding non-relevant stimuli, and is linked to activation of the dorsolateral prefrontal cortex (DLPFC). By administering functional Magnetic Resonance Imaging (fMRI) we have recently found that females with AN have increased activation in the DLPFC and reduced appetitive brain responses when thinking about eating food shown in visual images. This suggests that the increased WM capacity in AN may serve to suppress food intake, but this has not yet been clarified. In line with this assumption, we have also shown that restraint of appetite in those with AN was linked to greater plasticity in the DLPFC. Furthermore, Transcranial Magnetic Stimulation (TMS) of the DLPFC reduces appetitive responses to food stimuli in adults with eating disorders. Conversely, we have shown that being obese is linked to reduced structure and abnormal function in the DLPFC, as well as reduced attentional control/WM performance. Therefore, it is likely that DLPFC-related WM function is associated with eating disorders, particularly cognitive restraint of appetite.