Psychodynamic features in borderline personality disorder identified by a subliminal test, the Defense Mechanism Test.

Twenty-seven psychiatric inpatients, diagnosed according to DSM-III and the Diagnostic Interview for Borderline (DIB), and 7 healthy controls were tested with the Defense Mechanism Test (DMT), a test of subliminal perception based on psychoanalytic theory. In the test a specific stimulus is presented subliminally in a tachistoscope and the patient's perceptual distortions are registered. Patients with borderline personality disorder (BPD) were compared with patients with other personality disorders, patients with schizophrenic disorders and healthy controls. Specific perceptual distortions were identified among patients with BPD. Some individual DMT signs correlated with some deviant behaviors as identified by the DIB. The findings supported the psychodynamic validity of the concept of borderline personality disorder. It is concluded that DMT is a promising research instrument that provides an empirical approach to crucial psychodynamic phenomena.