[Pseudopolymelia and disorders of body scheme].

Two cases of pseudopolymelia are described. In the first case, a feeling of having one more left hand developed in a female patient after the ablation of an arteriovenous malformation of the splenium of the corpus callosum expended to the left cingulated gyrus. No movement and sensory disorders were found but "split brain" symptoms were observed. To the best of author's knowledge, this is a first description of such a case. In another female patient, the same feeling appeared, along with deafferent pain in the hand, due to tearing off the primary trunks of brachial plexus after the car accident. An analysis of literature and own data revealed that pseudopolymelia is observed in right-handers in the lesion of the deep right-hemisphere regions and accompanied by movement and sensory disturbances. Moreover, the feeling of phantom extremities appears in the lesion of the peripheral nervous system (deafferent phantoms), amputation of extremity and, what is most important, agenesia. Such findings raise a question on genetically determined engram of body scheme. The appearance of left-sided phenomena: pseudopolymelia, unilateral spatial ignorance, phenomenon of "strange hand", after the lesion of the right hemisphere in right-handers only as well as the corpus callosum argue for the common underlying mechanisms. The author suggests that they are based not only on the disturbances of analysis and synthesis of sensory information and movements (realized by the right hemisphere) but also on the defect of consciousness of stimuli realized by the left hemisphere, which can be connected to through the corpus callosum.