The term paraschematia comes from the Greek words para (beside, near, resembling, accessory to, beyond, apart from, abnormal) and schema (form, scheme, topographic map). It translates roughly as 'inadequate mapping of space'. The term paraschématie was introduced in or shortly before 1905 by the French neurologist Pierre Bonnier (1861-1918) to denote a variant of * aschematia characterized by an inadequate representation of the space occupied by certain body parts. Pathophysiologically, paraschematia is associated with lesions affecting the right parietal lobe. Because of its subjective nature, it cannot be observed directly in affected individuals. It can be inferred, however, from drawings in which the affected individual displays an inadequacy of spatial representations. Paraschema-tia is considered a productive and subconscious manifestation of neglect. It is usually classified as a variant of the * body schema illusion. The term paraschematia is used in opposition to the terms *hyperschematia and *hyposchematia.
References
Bonnier, P. (1905). L'aschématie. Revue Neurologique, 13, 605-609.
Dictionary of Hallucinations. J.D. Blom. 2010.