Models of mania: An individual case study.

Abstract

SummaryA longitudinal study of a single case of manic-depressive psychosis investigated the relationship between psychiatric ratings, reaction time and two measures of autonomic activity. Measurements were made on 19 occasions over a five-month period. The number of slow responses on the reaction time task increased with increasing depression. Manic periods appeared not to be characterized by a slowing of responses, but rather by an increase in the number of premature responses, i.e. those made to the warning signal. A derived performance index discriminated over the complete range from severe depression to severe mania.Increased depression was associated with lower heart rate resting levels, and increasing mania with increased skin conductance levels. An increased frequency of slow reaction times was significantly associated with lower resting heart rate. Skin conductance measures correlated significantly with the number of premature responses made on the reaction time tasks. Some differences in the relationships emerged when data obtained during the administration of lithium were included in the analysis.The results are discussed in relation to both the bipolar and the continuum models of manic-depressive psychosis. The latter model is not supported by the present investigation, since manic episodes were not characterized by a more severe departure from normality than depressive episodes on either the number of slowed responses or autonomic measures.