Anisotropy of the Drawing Plane in Focal Hand Dystonia: A Case Report and a Novel Postulate of Dysfunctional Tensorial Networks.

The pathophysiology of the dystonias has been associated with loss of inhibition in the sensory-motor cortex, brainstem and spinal cord, abnormal motor preparation in the pre-motor cortex, abnormal sensory processing in the sensory cortex, maladaptive plasticity and abnormal sensory-motor integration in the cerebral cortex. We present a case of focal hand dystonia with variance of spiral drawing in the horizontal and vertical planes, that is amelioration of spiral drawing in the vertical plane compared to the horizontal plane. We refer to this phenomenon as "anisotropy". We seize upon this unique finding and postulate a novel mechanism for the generation of the dystonias. The anisotropy referred to can only be explained by a breakdown of the tensorial transformation of a covariant vector to a contravariant vector in the frequency hyperspace of the brain. This novel hypothesis is based on the unequivocal invariance of tensorial transformation, a mathematical fact in differential geometry, the very geometry of the most celebrated and sublime General Theory of Relativity, and the model of dynamic brain function proposed by Pellionisz and Llinas.