EXPLAINING THE EFFECTS OF STIMULUS RESTRICTION - TESTING THE DYNAMIC HEMISPHERIC-ASYMMETRY HYPOTHESIS

The Restricted Environmental Stimulation Technique (REST) has been use d in hundreds of studies investigating the effects of drastically redu cing the accustomed flow of ambient information and stimulation. Some of this research has explored changes in basic psychological and psych ophysiological processes; other portions have been directed toward the application of REST, especially in clinical and health psychology. Al though a substantial data base now exists, no adequate theoretical exp lanation has been offered for the wide range of consistent and strikin g effects of REST on human beings. This paper describes several origin al experiments, and reviews the literature, assessing the evidence rel evant to one promising explanation: the Dynamic Hemispheric Asymmetry (DHA) model, which proposes that in REST the normally non-dominant cor tical hemisphere becomes more active and exerts greater influence over cognitive and affective processes. Research bearing upon the hypothes is includes work on memory, learning, imagery, divergent thinking, cre ativity, perception, habit modification, attitude change, hand dominan ce, and brain activity. The results offer only mixed support for the D HA model, but indicate areas for theoretical extensions and further re search.