Eating behavior depends heavily on brain function. In recent years, brain imaging has proved to be a powerful tool to elucidate brain function and brain structure in the context of eating. In this review, we summarize recent findings in the fast growing body of literature in the field and provide an overview of technical aspects as well as the basic brain mechanisms identified with imaging. Furthermore, we highlight findings linking neural processing of eating-related stimuli with obesity.
The consumption of food is based on a complex interplay between homeostatic and hedonic mechanisms. Several hormones influence brain activity to regulate food intake and interact with the brain's reward circuitry, which is partly mediated by dopamine signaling. Additionally, it was shown that food stimuli trigger cognitive control mechanisms that incorporate internal goals into food choice. The brain mechanisms observed in this context are strongly influenced by genetic factors, sex and personality traits.
Overall, a complex picture arises from brain-imaging findings, because a multitude of factors influence human food choice. Although several key mechanisms have been identified, there is no comprehensive model that is able to explain the behavioral observations to date. Especially a careful characterization of patients according to genotypes and phenotypes could help to better understand the current and future findings in neuroimaging studies.
aDepartment of Neurology, Max Planck Institute for Human Cognitive and Brain Sciences
bLeipzig University Medical Center, IFB Adiposity Diseases
cClinic for Cognitive Neurology, University Hospital, Leipzig
dMind and Brain Institute, Berlin School of Mind and Brain, Humboldt-University and Charité, Berlin, Germany
Correspondence to Maurice Hollmann, Department of Neurology, Max Planck Institute for Human Cognitive and Brain Sciences, Stephanstrasse 1A, D-04103 Leipzig, Germany. Tel: +49 (0) 341 9940 2433; fax: +49 (0) 341 9940 2221; e-mail: email@example.com