Is a homosexual orientation irreversible?

In four studies homosexual patients were randomly allocated to receive either different forms of aversive therapy; or aversive therapy or a positive conditioning procedure. Before and after therapy the patients' sexual orientation was determined by measuring their penile volume responses to moving pictures of nude men and women. The aversive therapies produced reduction in homosexual feelings and behaviour. In the fourth study the reduction was significantly greater following the aversive compared with the positive conditioning procedure. No significant change in measured sexual orientation occurred in the patients who received aversive therapy compared with those who received positive conditioning. The measured sexual orientation of the homosexual patients after treatment differed significantly from that of heterosexual patients who received aversive therapy for sexual anomalies.