Topics in Sleep Psychology Conducted in the Last Three Decades

Abstract

In this article, three experimental studies representing topics in Sleep Psychology conducted in the last three decades, outlined below are reviewed. 1. Verifying dream theory. The “activation-synthesis hypothesis” proposed by Hobson and McCarley (1977) and the “sensory image-free association hypothesis” proposed by Okuma (1992) were verified using event related potentials (ERP) time locked to the onset and offset of rapid eye movements (REM) during REM sleep. 2. Verifying sleep-dependent improvement of memory. A newly acquired visuomotor skill improved after one night of sleep. This sleep–dependent improvement in visuomotor performance was verified and it was established that the memory enhancement was closely related with sleep spindle activity. 3. Development of prophylactic napping. Often, there is increased sleepiness during the mid-afternoon and it is a cause of industrial and traffic accidents. A short nap of less than 20 minutes is proposed as an effective counter measure to prevent midafternoon sleepiness.