Subchronic hydrocortisone treatment alters auditory evoked potentials in normal subjects

Rationale: Abnormalities of cortical evoked potentials and background electroencephalographic (EEG) frequencies occur in several psychiatric disorders, some of which, especially depression, are associated with hypercortisolaemia. However, there have been few investigations of the effects of exogenously administered cortisol on waking EEG measures. Objectives: To examine the effects of subchronic hydrocortisone administration on auditory evoked potentials and background EEG activity. Methods: Hydrocortisone, 20 mg twice daily, or placebo was administered to 30 normal male volunteers for 7 days in a between-subjects, double-blind trial. Auditory evoked potentials and EEG frequencies were measured on the last day. Results: Hydrocortisone significantly increased the amplitudes of the N1P2 and P-300 components of the auditory evoked response, but there was no change in background EEG, Conclusion: The results indicate that subchronic hydrocortisone treatment in normal subjects increases the amplitude of auditory evoked potentials, possibly reflecting a central alerting effect.