Hodgkin's disease. I

Images

The informational underload (sensory deprivation) model in contemporary psychiatry

To summarize briefly: Converging data from many disciplines — psychology, psychiatry, social theory, biochemistry, neuropharmacology, neurophysiology — point to the sensory input regulating mechanism of the central nervous system as a critical factor in the production of hallucinoses and psychotic experience. There is good evidence that what we have called the informational underload model ‘holds considerable promise for improving our understanding of many clinical and non-clinical phenomena of interest to psychiatry. The evidence suggests that a neurophysiological, internal informational underload syndrome may be a final common pathway of psychotic experience. The question as to where such a syndrome might occur in the brain, together with the question of whether such an informational underload syndrome might be due to toxins, genetic factors, conditioning processes, anxiety or dissociation, or other causes, has to be left open. What is needed now, is research directed at these two questions: 1) does such an internal informational underload syndrome occur in the brain, 2) when, where, and under what circumstances does it occur?

Effect of a simple deconditioning procedure on the diuretic and natriuretic response of hypertensive patients to a hypertonic salt load

The increased diuretic and natriuretic response of hypertensive patients to an intravenous salt load was modified toward normal by a deconditioning procedure which consisted in repeated exposure to the external situation of the test without, however, infusing any fluid into the vein. After this deconditioning, ratios between amounts of urine and sodium excreted in the first and the second 90-minute period of the test and the total 3-hour quantity of urine excreted were significantly reduced, but blood pressure was not changed. The response of normotensive patients to the same deconditioning was modified in the same direction but to a much smaller extent. It is suggested that the increased diuretic and natriuretic responses of hypertensive patients to an intravenous salt load are similar to the hyperreactive pressor and diuretic responses of these patients when exposed to stimuli that seem threatening to them, and that these responses are caused (at least in part) by hyperreactivity of the central nervous system to the external situation of the test.