High-dose infusion therapy for severe depressions.

The present paper reports the results of high-dose intravenous antidepressive treatment performed at the Psychiatric Department of the Hungarian Central Hospital in Budapest. Based on the differences in the comparative dexamethasone suppression tests (DSTs), prolactin (PRL) responses and Fischer Symptom Check List (FSCL) scores, it is hypothesized that a high parenterally administered dose of dibenzepine acts differently in comparison to oral drugs, which are extensively metabolized in the hepatic microsomal system. The results obtained so far suggest that the effect of high-dose intravenous dibenzepine in endogenous depressive states is comparable to that of electroconvulsive therapy (ECT), as far as the regression of symptoms and biochemical changes are concerned.

Dexamethasone suppression test and coping behavior in psychosocial stress.

The dexamethasone suppression test (DST) and the Minnesota Multiphasic Personality Inventory (MMPI) were administered to 144 healthy inductees on day 2 of military service. One hundred and four of them completed a 120-item questionnaire describing their coping responses to this particular challenge. Thirty-six subjects (25%) failed to suppress plasma cortisol adequately. Their mean scores on the MMPI clinical standard scales were within the normal range. High postdexamethasone cortisol levels were associated with denial and passivity, and with low demand for social support. These results suggest that the DST might be more related to coping with a stressor than to a specific diagnosis. The authors speculate that high hypothalamic-pituitary-adrenal activity may have a primary role in psychological defense promoting inattention to the aversive aspects of stressful situations.

Maintenance of signal directed behavior in a response dependent paradigm: a systems approach.

Rats were trained in a straight alley to repeatedly press a bar placed at one end of the alley until a discriminative signal (SD) appeared and to run for water reward (Rd) available at the other end. During training SD was spatially contiguous with Rd, then SD was placed above the bar (spatially discontiguous with Rd). In Experiment I subjects were trained for ten days, in Experiment II to equal level of performance before cue rearrangement. Experiment III applied systems analysis. Making SD spatially discontiguous with Rd caused abrupt and characteristic changes in many of the parameters observed (e.g., start-time, bar press perseveration, bar press topography, rearing, intertribal runs, defecation). If rats were initially trained under SD -Rd spatial discontiguity condition, making SD spatially contiguous with reward did not deteriorate their performance. It was concluded that: (i) rats learn and maintain responding to informative signals also in response dependent paradigms, (ii) spatial location of cue is of substantial importance for animals, and cue rearrangement will necessarily modify the topography of the learned response, (iii) the findings exclude the adventitious reinforcement explanation of signal directed behaviors, and question the validity of the concept of equivalent associability.