Individual differences in stimulus intensity modulation and its relationship to two styles of depression in older...

Research comparing depressive persons with and without manic symptoms shows striking parallels with differences between augmenters and reducers on the Kinesthetic Aftereffect (KAE) task (A. Petrie, 1967). Twenty-three community-dwelling older adults identified by the Minnesota Multiphasic Personality Inventory (S. R. Hathaway & J. C. McKinley, 1951) as depressive without manic symptoms were compared with 24 older adults with manic symptoms on the KAE, the NEO Personality Inventory (NEO-PI; P. T. Costa & R. R. McCrae, 1985), and Strelau (J. Strelau, 1983) Temperament Inventory. As hypothesized, augmentation was related to depression without manic symptoms, and reduction was related to depression with manic symptoms. Stepwise discriminant analyses indicated that the KAE is a potent discriminator between the 2 types of depression. Three characteristics of Strelau's "strength of nervous system"--excitation, and inhibition and mobility--discriminate significantly between the 2 groups as well as NEO extraversion and conscientiousness. Results suggest that older depressive persons with and without manic symptoms may benefit from different therapeutic interventions.