EFFECT OF VARIATION IN PERCEIVED RISK ON THE SECRETION OF BETA-ENDORPHIN

It is currently unknown why individuals opt to participate in risk tak ing as a form of recreation. This study was designed to test the hypot hesis that beta-endorphin, a naturally produced opiatelike peptide, is secreted in response to a perception of risk thereby reinforcing risk -taking behaviors. A 2 x 2 factorial design (Time x Perceived Risk) wi th repeated measures across both factors was used. The two levels of t ime were pre- and postexposure to a particular level of perceived risk . The two levels of perceived risk were high and low. Perceived risk w as operationalized through the use of ropes course events of similar d esign but differing in exposure to height. The dependent variable was level of plasma beta-endorphin. Exploratory analyses of subjective aro usal, pleasure, and desire to repeat were also undertaken. Results ind icated that plasma beta-endorphin and arousal were significantly incre ased in the high perceived-risk condition. A Time x Risk interaction w as identified for subjective pleasure. Although the means were in the hypothesized direction, no significant difference was found between lo w- and high-risk conditions for desire to repeat the experience.