The trial court did not err in preventing defendant from testifying that he had an extensive history of hearing voices, flashbacks, and blackouts, in this capital case in which he was charged with first degree felony-murder under the theory the murder occurred during a rape. Although defendant claimed it would show he lacked intent to rape, defendant testified he heard voices after the rape and murder; he did not testify the voices told him to attack the victim. Any prior history of hearing voices would have been irrelevant. Moreover, any error was harmless since not even the defense psychiatrist testified to any such psychiatric history.