Lateralization of defence mechanisms: Differing influences on perception with left and right visual field presentation of anxiety-arousing stimulation

Forty-five undergraduate students were randomly divided into two groups and tested with the Meta-Contrast Technique (MCT), in the left or right visual field (VF). In the MCT, the presentation of a subliminal threatening picture is intended to evoke anxiety and ego mechanisms of defence against it. More signs of repressive plus isolating defences were found in the left hemisphere (LH) group. Signs of projection plus regression tended to be more common in the right hemisphere (RH) group. The total number of anxiety signs in the MCT protocols did not differ between the groups. A clear sex difference was noticed, namely that the female LH and RH groups showed significant lateralization, while the male groups did not differ significantly on a combined defensive score. The data suggest that the left and right hemispheres may show differing perceptual styles, which are described as ego mechanisms of defence in the psychoanalytic literature.