Ever since E.C.T. was introduced it has been observed that complaints of impaired memory are very common after this form of treatment, but also that the complaints vary considerably in different patients. That memory performances—as they may be measured by means of tests—are disturbed to a varying degree after E.C.T. has been established by several authors. It is thus reasonable to assume that the varying complaints of impaired memory, at least in part, reflect true disturbances of memory abilities. It is a common impression, however, that patients who have gained an obvious release from emotional distress comparatively seldom complain of memory disturbances after E.C.T. Thus, the complaints of memory impairment seem to be determined also by another factor, acting in the opposite direction, viz., improvement of disease. No investigation of the extent to which various factors have influenced the complaints of memory disturbances after E.C.T. seems to have been made.