BRAIN-STEM AUDITORY-EVOKED POTENTIALS OF PANIC DISORDER PATIENTS

Panic attacks are subjectively reported by patients as a cluster of au tonomic nervous symptoms, Taken together with the evidence from pharma cological studies focusing on the locus ceruleus and the dorsal raphe nuclei, the hypothesis of brainstem involvement in panic attacks is of major interest. Functional evaluation of the brainstem is carried out using electrophysiological recordings, such as the brainstem evoked p otentials. We have investigated the pathophysiology of these parameter s in 16 patients fulfilling the DSM III-R criteria for panic disorder (8 females and 8 males) in comparison to a group of 10 normal controls , The patients were found to have two electrophysiological variables s ignificantly different from controls: (a) N3 latency tme was reduced ( P < 0.05) and (b) tile N3-5 interval was prolonged (p < 0.05). The N3 latency period significantly correlated with the Hamilton Anxiety Scal e scores (p < 0.005). N3 is a peak reflecting pontine activation, wher e the locus ceruleus is located, The N3-5 interval reflects evoked pot ential passage from the pens to the midbrain. In conclusion, our resul ts support previous studies indicating a dysfunction of the locus ceru leus possibly causing disruption of pens-midbrain transmission in pati ents suffering from panic disorder.