Abstract : In the present study, a false feedback paradigm was used to manipulate the experience of seventy-six men to produce a discrepancy between actual and expected sexual performance. Thirty-nine men were diagnosed with male erectile disorder due to psychogenic factors, while the other thirty-seven were sexually functional. Experimental participants were provided within flated feedback concerning the size of their erections while they viewed an erotic videotape. By examining changes in expectations of sexual performance, confidence, and tumescence overtime, the impact of false feedback on sexual function was experimentally evaluated. It was proposed that inflated feedback would differentially modify cognitive set and penile tumescence in sexually functional and dysfunctional men. Based on prior studies, experimental groups were expected to show decreased erectile response, despite receiving inflated feedback. Functional men were expected to increase expectancies, while those of dysfunctional men were expected to decrease. Furthermore, functional men were expected to regain tumescence with additional exposure to erotica. Dysfunctional men were not expected to restore tumescence. Functionals responded to inflated feedback by increasing their expectancy associated with the feedback itself. While predicted tumescence and confidence did not increase, the functional men believed they experienced larger erections. Dysfunctionals also believed they had larger erections and were more surprised by the inflated score than the functionals. However, dysfunctional men did not increase expectancies or confidence.