In this paper are given the histories of ten patients who have been treated by means of leucotomy, particular attention being paid to the study of character and personality traits.

The records are compiled from the information given by a relative or relatives, supplemented in some cases by data supplied by the patient as well. This method undoubtedly has serious disadvantages, for the information must inevitably be dependent upon the informant's veracity, powers of observation and description, memory, and conscious and unconscious subjective bias. In every case the interview took place at the patient's home, so that the interviewer could obtain a personal impression of the patient's home environment. Furthermore, the information regarding the pre-morbid personality was only obtained after the illness, operation, and recovery, and in some cases it was difficult to ascertain when the morbid changes actually began.