A categorical approach to the study of amygdala volumes in specific neuropsychiatric disorders leads to contradictory findings. In an alternative dimensional approach, we tested the hypothesis that amygdala volume loss represents specific dimensions of affective syndromes in patients with epilepsy. One hundred sixty patients with chronic therapy-refractory epilepsy were carefully diagnosed for psychiatric symptoms. Fifty-three patients without any lifetime psychopathology (n=24), with dysphoric disorder of epilepsy (n=12), or with major depressive disorder (n=17) were included. Amygdala and hippocampal volumes were measured using established protocols. Amygdala volumes were significantly reduced in patients with dysphoric disorder of epilepsy and correlated significantly with core symptoms of dysphoric disorder of epilepsy, that is, emotional instability, dysphoria, irritability, and aggression. Our finding supports a dimensional concept of the meaning of brain alterations and validates the clinical concept of dysphoric disorder of epilepsy.