VERTICAL INVERSION OF THE VISUAL-FIELD AND REM-SLEEP MENTATION

The effects of the vertical inversion of the visual held on REM sleep mental activity were examined to explore the potential involvement of this activity in information processing. In a first experiment, four m ale subjects slept in the laboratory for two sessions of 6 consecutive nights: 2 adaptation nights, 2 nights of polysomnography and 2 nights of dream collection. During the days preceding Nights 3, 4, 5, 6 of e ach session, the subjects wore glasses which, during the second sessio n, completely inverted (rotation of 180 degrees) their visual held. In a second experiment with four other male subjects, the order of condi tions was reversed and the experimental condition (visual inversion) w as introduced twice. The data of the two experiments were combined. Ov erall, following visual inversion, there were significant increases in the proportion of dreams containing motor and visual difficulties (P < 0.005), misfortunes (P < 0.05) and dreamer confusion (P < 0.05) and a decrease in dreamer participation (P < 0.05), Only 4 of the 8 subjec ts experienced incorporations of the inverted visual field into their dreams and they tended to perform better on two of three tests of adap tation to the visual inversion. The observed changes in dreams are con sistent with the notion of continuity between waking and dreaming sinc e they appear to reflect the waking preoccupation and psychological st ate associated with visual inversion.