The 'psychic' experiences of 17 students (sensitives) from the College of Psychic Studies were compared with those of 17 church-going control subjects, who were matched for age, sex, and approximate intellectual level. At interview, 67 items of information relating to the medical history, family history, 'psychic gifts', head injuries, and mystical experiences were obtained. The shortened WAIS, the Benton Visual Retention Test, with tests of both dominant (Wechsler Logical Memory) and non-dominant temporal lobe function (the Rey-Osterreith Test) were given. The results showed that the sensitive population contained more single or divorced people, and people who had sometime consulted a psychiatrist. They had experienced more head injuries and serious illnesses than the controls. Sixty-six per cent showed evidence of right hemisphere and right temporal lobe dysfunction and, of these, 35 per cent had poor visual memories. There was evidence to suggest that some 'psychic' experiences were associated with brain dysfunction. Despite an increased occurrence of head injury, no clear correlation with the onset of 'psychic' sensitivity was found. Mystical experiences showed a trend towards being related to non-dominant hemisphere dysfunction. Vagueness about the position of the sensitive's 'psychic helper' in physical space was also associated with non-dominant hemisphere dysfunction.