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This paper describes a patient with an almost 48-hour manic-depressive cycle but with a daily shift of the switching time, the latter having itself a cycle of five days. The mood change always occurred gradually and during the day, never at night. Between manic and depressive phases there was a difference in the frequency of the EEG alpha rhythm. The patient showed a good response to lithium treatment.
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Paschalis et al. (1980) studied this question.
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