EFFECTS OF SOMATOSENSORY STIMULATION ON DREAM CONTENT IN GYMNASTS ANDCONTROL PARTICIPANTS - EVIDENCE OF VESTIBULOMOTOR ADAPTATION IN REM-SLEEP

Somatosensory stimulation of the leg muscles in REM sleep appears to p erturb virtual orientation in dream experiences. According to our mode l of vestibulomotor adaptation (Sauvageau, Nielsen, & Montplaisir, 199 6), the dreaming mind attempts to compensate for such destabilizing st imulation by increasing eye movement activity or by modifying dream co ntent, among other possible reactions. Effective compensation may be m ore easily achieved by participants who are adapted to the disruptive stimulation or who possess highly developed vestibulomotor skills. To examine this possibility, we studied the effects of somatosensory stim ulation on the dreams of 6 gymnasts and 6 control participants aged 9 to 16 years. Results provide some support for the expectations that 1) imposed somatosensory information is processed by the central nervous system in REM sleep, 2) unilateral stimulation induces an upset in vi rtual orientation 3) gymnasts are more resistant to these disruptive e ffects of stimulation than are control participants, and 4) because of long-term adaptation, the dream content of gymnasts does not differ m arkedly from that of controls. Though preliminary and in need of repli cation, the findings are compatible with the notion that the developed vestibular skills of gymnasts protects them to some extent from the e ffects of a disruptive somatosensory stimulus during sleep.