Brain dopamine is associated with eating behaviors in humans

Objective: Eating behavior in humans is influenced by variables other than just hunger-satiety including cognitive restraint, emotional distress, and sensitivity to food stimuli. We investigate the role of dopamine (DA), a neurotransmitter involved with food motivation, in these variables. Methods: We used the Dutch Eating Behavior Questionnaire (DEBQ) to measure Restraint, Emotionality, and Externality in 10 subjects. We correlated DEBQ scores with brain DA levels. Positron emission tomography and [¹¹C]raclopride uptake were used to measure baseline D₂ receptors (neutral stimulation) and to assess changes in extracellular DA to food stimulation (display of food). Results: Restraint was correlated with DA changes with food stimulation (higher restraint, greater responsivity), emotionality was negatively correlated with baseline D₂ receptors (higher emotionality, lower D₂ receptors), whereas externality was not. These correlations were significant in the dorsal but not in the ventral striatum. Discussion: These results provide evidence that DA in the dorsal striatum is involved with the restraint and emotionality components regulating eating behavior and that these two dimensions reflect different neurobiologic processes.