The term microsomatognosia comes from the Greek words mikros (small), soma (body), and gnosis (insight). It translates roughly as 'experiencing the body as smaller'. The term was introduced in or shortly before 1963 by the Dutch neurologist Joseph Antonius Maria Frederiks to denote a disorder of the body scheme in which the body, in part or in whole, is experienced as disproportionally small. When the whole body is involved, the expressions * whole body microso-matognosia and total body microsomatognosia may be used. When the condition is restricted to one or more parts of the body, the term *partial microsomatognosia may be used. The phenomenon itself was described as early as 1905 by the French neurologist Pierre Bonnier (1861-1918), in the context of *aschematia. Frederiks lists three general characteristics of micro-somatognosia, i.e. (1) its paroxysmal character, (2) its occurrence in both halves of the body, and (3) its occurrence in the unclouded mind. Microsomatognosia may present as an isolated symptom, as part of an *aura, as part of a cluster of symptoms called the *Alice in Wonderland syndrome, or as part of the cluster of symptoms designated as * schizophrenia. Etiolog-ically, it is associated with a variety ofconditions, including epileptic seizures, migraine, * delirium, *delirium tremens, alcohol withdrawal, toxo-plasmosis or typhoid infections, mesencephalic lesions, and intoxication with * hallucinogens such as LSD and mescaline. Microsomatognosia may also occur as a transient phenomenon during * hypnagogic states. The condition is generally classified as a *body schema illusion or as a type of somatognosia. The term microsomatognosia is used in opposition to *macrosomatognosia.

References

Bonnier, P. (1905). L'aschématie. Revue Neurologique, 13, 605-609.

Frederiks, J.A.M. (1963). Macrosomatognosia and microsomatognosia. Psychiatry, Neurology and Neurosurgery, 66, 531-536.

Podoll, K., Robinson, D. (2000). Macrosomatognosia and microsomatognosia in migraine art. Acta Neurologica Scandinavica, 101, 413-416.