Per son. indir r d. Of &? Vol. IO. No. 6, pp. 671-679. 1989 Prmred in Great Britain. All rights reserved 0191-8869 89 S3.00+0.00 Copyright C 1989 Pergamon Press plc SENSATION SEEKING AND AROUSAL: EFFECTS OF STRONG STIMULATION ON ELECTRODERMAL ACTIVATION AND MEMORY TASK PERFORMANCE BARRY D. zyxwvutsrqponmlkjihgfedcbaZYXWVUTSRQPONMLKJIHGFEDCBA SMITH,’ * ROBYN A. DAVIDSON,’ DEBRA L. SMITH,’ HAROLD GOLDSTEIN’ and WILLIAM PERLSTEIN” ‘University of Maryland, College Park Campus. College Park, MD 20742441 I and *University of Delaware, Newark, DE 1971I, U.S.A. (Received 18 April 1988; received zyxwvutsrqponmlkjihgfedcbaZYXWVUTSRQPONMLKJIHGF for publicarion I I August 1988) Summary-The frequently observed behavioral effects of the sensation-seeking dimension may be based in a biological substrate involving the reticulocortical activation system and the catecholamine system. Under this theory, high sensation seekers should exhibit elevated levels of psychophysiological arousal as compared with low sensation seekers. Subjects in the present study were exposed to a series of auditory sexual and violent stimuli at three levels of intensity and later required to perform recall and recognition memory tasks involving these stimuli. A vigilance task was also employed. Results showed that phasic electrodermal response amplitude was significantly higher in high than low sensation seekers on a variety of measures, including initial response amplitude and intertrial amplitude. Moreover, the size of these personality group differences increased as a function of increasing stimulus intensity. Findings were interpreted as supporting the theory that high sensation seekers should be more responsive to stimulation as a result of their hypothetically more excitable central nervous systems. Recent research growing out of Zuckerman’s (1969, 1979) sensation-seeking theory has frequently and quite consistently demonstrated behavioral differences between groups of Ss at the two extremes of the sensation-seeking dimension. For example, sensation seeking is positively related to abuse of a variety of drugs, including amphetamines, marijuana, hashish, and psychedelics (Brill, Crumpton and Grayson, 1971; Carrol and Zuckerman, 1977; Kaestner, Rosen and Appel, 1977). Similarly, sensation seeking shows positive relationships with such varied activities as scuba diving (Heyman and Rose, 1980), cigarette smoking (Stanaway and Watson, 1981), sexual activity (Zuckerman, Tushup and Finner, 1976), and sport parachuting (Hymbaugh and Garrett, 1974). As Zuckerman has frequently pointed out, the common thread underlying the variety of activities that contrast high and low sensation seekers is the differential tendency of those high on the scale to seek and respond to novel, varied, and arousing stimulation. The observed behavioral effects of the sensation-seeking dimension suggest that it may be based in a biological substrate involving the reticulocortical activation system (Zuckerman, 1969; Zuckerman, Murtaugh and Siegel, 1974) and possibly the catecholamine system associated with the locus coeruleus (Zuckerman, 1984). Such a biologically based dimension should hypothetically have differential effects not only on behaviors but on activation or arousal, which can be measured psychophysiologically (Neary and Zuckerman, 1976; Smith, Perlstein, Davidson and Michael, 1986). In particular, it would be hypothesized that high sensation seekers (HSS) exhibit higher levels of psychophysiological arousal than low sensation seekers (LSS). While the sensation-seeking/arousal hypothesis seems straightforward, results from the small number of studies completed to date have been mixed. Some studies have found no psychophysio- logical differences between the two sensation-seeking groups (Cox, 1978; Ridgeway and Hare, 1981), while others have reported larger electrodermal responses to an initial stimulus in HSS as compared with LSS (Feij, Orlebeke, Gazendam and van Zuilen, 1985; Neary and Zuckerman, 1976; Stelmack, Plouffe and Falkenberg, 1983; Zuckerman, 1972) and reduced motoneural excitability in high disinhibitors (Pivik, Stelmack and Bylsma, 1988). Only two studies to date have provided evidence that differences in electrodermal activity between high and low sensation seekers exist beyond the initial stimulus in the series. One of these studies demonstrated the occurrence of *To whom all reprint requests should be addressed. 671