The Assessment of Deviant Sexual Arousal as a Function of Intelligence, Instructional Set and Alcohol Ingestion

Abstract

Sexual offenders who had been referred for a forensic evaluation were assessed in terms of their deviant sexual arousal by means of standard penile plethysmographic procedures. The sample was divided into Rapist and Nonrapist groups according to their sexual history and criminal charges. Penile circumference responses (PCR) and self-reported arousal to consenting sex, sexual assault, and physical assault were monitored. The assessments were repeated following subject instructions to suppress their arousal and following the ingestion of alcohol. The overall correlation between PCR and self-reported arousal was .65. An Alcohol-by-Offender Type interaction revealed that the lowering effect of alcohol on PCR occurred only among the Nonrapists. The suppression instruction increased Rapists' PCRs to Rape and Physical Assault presentations relative to consenting sexual narrations. When the data were examined in relation to intelligence, low IQ Rapists displayed greater responses to rape than high IQ Rapists. Under the influence of alcohol, low IQ Rapists displayed greater arousal regardless of the stimulus, while high IQ Rapists showed no change, and Nonrapists responded less than they did without alcohol. Comments concerning the accurate assessment of deviant sexual arousal and the identification of precursors to deviant sexual behaviour are made in view of the current findings.

Alcohol and erectile response: The effects of high dosage in the context of demands to maximize sexual arousal.

“…Attenuation effects also emerged in three subsequent experiments (Wilson, Lawson, & Abrams, 1978;Wilson, Niaura & Adler, 1985;Wormith, Bradford, Pawlak, Borzecki, & Zohar, 1988) and a case study (Cooper, 1994). Alcohol-induced attenuation of genital arousal seemed conclusive.…”

Phallometric Assessment of Sexual Arousal

“…In their early work, Wilson, Lawson, and Abrams (1978) demonstrated that alcohol has the effect of diminishing sexual arousal. Contrasting results were offered by Wormith et al (1988) who found that alcohol consumption increased overall erectile response of people with lower IQ scores. Interestingly, while intoxicated nonoffenders had lower arousal responses, rapists displayed no change in their patterns after alcohol consumption.…”

“…Nevertheless, research outcomes consistently report reasonable correlation coefficients between self reported and phallometrically measured arousal (see Murphy & Barbaree, 1994). For example, Wormith et al (1988) reported a correlation of r ¼ .65 between outcomes of phallometry and selfreported sexual preference; and Laws et al (2000) observed high correlations between penile results and a self-report card sort of sexual preference.…”

“…The correlation between IQ and deviance score was confirmed by other studies, and previous reviews suggested lower faking abilities in subjects with lower IQ as a mediating variable (Marshall & Fernandez, 2003;Murphy & Barbaree, 1994). We could only identify one study by Wormith, Bradford, Pawlak, Borzecki, and Zohar (1988) where lower IQ was associated with lower overall arousal.…”

“…Interestingly, the instruction to suppress arousal may even enhance the discriminative power of a phallometric assessment. Wormith et al (1988) asked their sample of rapists to inhibit erectile responses. While this appeared easy to do with consenting scenes, it was much harder for them to suppress responding on material describing rape or physical assault, suggesting that it is harder to inhibit responding driven by stronger sexual preferences.…”