ABSTRAC~In the framework of a major longitudinal study of depressive disorders, 11 female and 5 male depressives were audio-video-recorded while speaking with clinical interviewers. For selected utterances during depressed and recovered mood states several voice and speech parameters were obtained, using digital analysis techniques. As predicted, the results showed that an increase in speech rate and a decrease in pause duration are powerful indicators of mood improvement in the course of therapy (remission from depressive state). In female but not in male patients, a decrease in minimum fundamental frequency of the voice predicted mood improvement. These effects are discussed with respect to neurophysiological, cognitive, and emotional factors that have been suggested in the literature as possible causes for the patterns of motor expression observed in depressives. The data also point to the urgent need to systematically study gender differences in depressive speech behavior.One of the major issues in the treatment of psychopathological disorder is the behaviorally based evaluation of progress in therapy. This problem is particularly troublesome in charting changes of mood during therapy of patients with affective illness. In general, mood evaluation scales and psychiatric diagnoses are used for this purpose. Unfortunately, neither of these approaches is entirely satisfactory, given the multiple sources of error, particularly in relation to patients' ability and willingness to communicate about their actual state and the difficulties in clinical inference of mood state on the basis of interview impressions. As a consequence, there has been renewed interest in the possibility of using objective behavioral This study is based on psychiatric interviews that were conducted as part of the Longitudinal Study on Depression at the Max-Planck-lnstitute for Psychiatry, Munich. The authors acknowledge the contribution of Rudolf Bildhauer and Thomas Klos, who performed the vocal analyses (as part of their theses in partial fulfillment of the requirements for a degree in psychology) and who contribUted to an earlier draft of this paper. Torn Johnstone and Marcia Smith provided valuable comments on the present manuscript.Requests for reprints should be directed to: Prof.
