In a clinical study of cases of mild organic brain damage the authors contrast their findings with the Goldstein-Scheer hypothesis linking the psychological disturbances due to brain damage with the loss of the abstract attitude. These milder cases are characterized by a contraction of the sphere of consciousness and a sense of instability of the data of consciousness. The present study did not suggest which phenomenon was primary. Compensatory reactions and defense mechanisms are called into play to cope with these deficits. The manifestations of the coping mechanisms are what we observe in the concreteness, rigidity, compulsiveness, denial, etc. attendant upon organic brain impairment.