Sexual Arousal as a Function of Stimulus Mode: Implications for Phallometric Assessment

Though phallometric assessment is no stranger to controversy it is still a procedure which is widely recognized as having considerable value. Researchers have cited it as a reliable means to assess age and gender preferences and to assess a preference for coercive versus consenting sexual activities. It is also the only method which allows a determination of an offender’s ability to inhibit deviant sexual arousal, a factor of principal importance is assessing risk of reoffending. This procedure is weakened, however, by the problem of low arousal, and often results are deemed too low to be interpreted. A factor contributing to low arousal may be the widespread availability of pornographic material on the internet, for this may desensitize participants to weaker stimuli used in some labs. In response to ethical concerns some labs have adopted the use of audio stimuli alone, and this may compromise the procedure. This study compares arousal to consenting adult heterosexual, adult female rape, and heterosexual pedophilia themes in response to audio versus slide versus video stimuli. Results from 142 incarcerated inmates reveal that visual stimuli are most effective and that the use of audio stimuli alone often yields sexual arousal profiles which are too low to be interpretable.