A peculiar type of behavior disorder consisting of an apparent conflict between the desired and the actually performed act is described in 2 epileptics following partial and complete callosal section. The psychobiological and psychoneurological aspects of this diagonistic type of dyspraxia is discussed. It is concluded that in the first case psychobiological factors played a major rôle in the etiology of the disorder, and that in the second case the diagonistic dyspraxia was probably an epileptic variant.Abstract Teaser