Assessing deviant sexual arousal: Physiological and cognitive aspects

Abstract

The physiological assessment of deviant sexual arousal is addressed. Concentration is focused on penile plethysmography because of its simplicity, accuracy, and widespread use. The sexual assessment technology is discussed in terms of measurement, reliability, validity, self-reported arousal, faking, and instructional procedures.

Thirty-six federally incarcerated offenders were assessed in the standard manner for their deviant sexual orientation. Rapists, Pedophiles, and Nonsex Offenders were shown two sets of stimulus slides approximately one week apart. The six slide categories were Neutral (Landscape), Child Male, Adult Male, Child Female, Adult Female, and Couples. During one testing session, subjects were asked to verbally describe each slide during the stimulus presentation. At slide offset, subjects were asked to subjectively rate each slide. Physiological response was the base-to-peak amplitude of penile circumference change during each slide presentation.

The two forms of the test for sexual orientation were considered parallel. Internal consistency, test-retest (one week), and parallel form reliability coefficients were acceptable. A multitrait-multimethod analysis favoured the physiological data set over the self-reports. Pedophiles responded physiologically and subjectively to Child Males in comparison to other groups. Both the physiological and self-report data sets successfully allocated 64% of the subjects to their actual groups. Groups were also differentiated on the basis of their pattern of verbal descriptions to stimulus slides. Rapists were most verbal although they focused on irrelevant and nonsexual aspects of the slides. Pedophiles were least verbal and avoided descriptions of sexual characteristics. Nonsex Offenders were more likely to report appealing features of the stimulus models.