Vicarious viewing time: prolonged response latencies for sexually attractive targets as a function of task- or stimulus-specific processing.

The amount of time an individual spends gazing at images is longer if the depicted person is sexually appealing. Despite an increasing use of such response latencies as a diagnostic tool in applied forensic settings, the underlying processes that drive the seemingly robust effect of longer response latencies for sexually attractive targets remain unknown. In the current study, two alternative explanations are presented and tested using an adapted viewing time paradigm that disentangled task- and stimulus-specific processes. Heterosexual and homosexual male participants were instructed to rate the sexual attractiveness of target persons differing in sex and sexual maturation from four experimentally assigned perspectives--heterosexual and homosexual perspectives for both sexes. This vicarious viewing time paradigm facilitated the estimation of the independent contributions of task (assigned perspective) and stimuli to viewing time effects. Results showed a large task-based effect as well as a relatively smaller stimulus-based effect. This pattern suggests that, when viewing time measures are used for the assessment of sexual interest, it should be taken into consideration that response latency patterns can be biased by judging images from a selected perspective.