Auditory brain stem response (ABR) in anorexia nervosa.
Auditory brain stem responses were recorded in 20 patients with anorexia nervosa and 10 normal control subjects. Twenty patients were studied during two phases of illness, 1) anorexia nervosa group with under weight (U-AN group), and 2) anorexia nervosa group with recovered normal weight (N-AN group). Absolute latencies, interwave latencies, absolute amplitudes, and amplitude ratios were investigated. A nonsignificant difference was found among these groups as far as the latencies were concerned. Both the patients in the U-AN group and those in the N-AN group had significantly smaller amplitude ratios (III/I, IV.V/I) and absolute amplitude (V) than did the control subjects. Furthermore, a nonsignificant difference was found between the U-AN group and the N-AN group. It suggests that some dysfunction might exist in the region of the brain stem.