Split-brain is a lay term to describe the result when the
corpus callosumconnecting the two hemispheres of the brainis severed to some degree. The surgical operation to produce this condition is called corpus callosotomy. It is performed rarely, usually as a last resort in otherwise intractable epilepsy: to mitigate the risk of accidental physical injury by reducing the severity and violence of epileptic seizures.
A patient with a split brain, when shown an image in his or her left visual field (that is, the left half of what both eyes see), will be unable to name what he or she has seen. This is because the speech-control center is in the left side of the brain in most people, and the image from the left visual field is sent only to the right side of the brain. (Those with the speech control center in the right side will experience similar symptoms when an image is presented in the right visual field.) Since communication between the two sides of the brain is inhibited, the patient cannot name what the right side of the brain is seeing. The person can, however, pick up and show recognition of an object (one within the left overall visual field) with their right hand, since that hand is controlled by the left side of the brain.
Some of the earliest split-brain research was carried out by
Roger Wolcott Sperry, and continued when he was joined by Michael Gazzaniga. Results from this research have led to important theories on the lateralization of brain function.
Split-brain patients may sometimes confabulate a rational account of their behavior, if the true motivations cannot be reported since they may depend on processing in the linguistically inaccessible right side of the brain.
There are some theories that the different hemispheres may have different "personalities" and contradictory goals. In the stage production, book and film of "Thursday's Fictions" by
Richard James Allen, the brain of a character named "Friday" splits when he cannot face the consequences of his actions. A debate between the two halves of his brain ensues, one half seeking to remember, the other half to forget.
* [http://www.epilepsy.com/epilepsy/corpus_collostomy.html Detail on the callosotomy procedure] from epilepsy.com
* [http://www.indiana.edu/~pietsch/split-brain.html Interesting summary with further links to follow]
* [http://nobelprize.org/medicine/educational/split-brain/index.html An animated game that illustrates the split-brain experiments.]
* [http://www.hypnosisschool.org/50.php Split Brain Demonstration Video]
* [http://www.abc.net.au/rn/allinthemind/stories/2008/2276587.htm Michael Gazzaniga: Split brains and other heady tales on ABC Radio National's "All in the Mind"]
* [http://www.ted.com/index.php/talks/jill_bolte_taylor_s_powerful_stroke_of_insight.html Jill Bolte Taylor: My stroke of insight on TED]
Alien hand syndrome
A Scanner Darkly, a science fiction novel whose protagonist's brain splits throughout the narrative.
Wikimedia Foundation. 2010.
Look at other dictionaries:
split-brain — split .brān adj of, relating to, concerned with, or having undergone separation of the two cerebral hemispheres by surgical division of the optic chiasma and corpus callosum <split brain research> <split brain patients> … Medical dictionary
split brain — ● split brain nom masculin Synonyme de encéphale dédoublé. ● split brain (synonymes) nom masculin Synonymes : encéphale dédoublé … Encyclopédie Universelle
split-brain — split′ brain′ adj. psl pat having, involving, or pertaining to a separation of the cerebral hemispheres by severing the corpus callosum • Etymology: 1955–60 … From formal English to slang
Split Brain — Corpus callosum (19), frontaler Schnitt Split Brain (englisch: geteiltes Gehirn) bezeichnet in der Medizin den Zustand nach der neurochirurgischen Durchtrennung des Corpus callosum, welches die beiden Hirnhemisphären miteinander verbindet. Den Ei … Deutsch Wikipedia
split-brain — ¦ ̷ ̷ ¦ ̷ ̷ adjective : of, relating to, concerned with, or having undergone separation of the two cerebral hemispheres by surgical division of the optic chiasma and corpus callosum behavior in split brain animals split brain research * * *… … Useful english dictionary
Split-brain — Un split brain se produit lorsque deux parties d un cluster d ordinateurs sont déconnectées, chaque partie croyant que l autre ne fonctionne plus. Le terme est une analogie médicale du syndrome split brain. Les clusters à haute disponibilité… … Wikipédia en Français
split brain — a brain in which connections between the hemispheres, mainly the corpus callosum, have been severed or otherwise disrupted; done surgically on experimental laboratory animals and in humans to provide access to the third ventricle or to control… … Medical dictionary
split-brain — adjective Date: 1958 having the optic chiasma and corpus callosum severed < behavior in split brain animals > … New Collegiate Dictionary
split-brain — /split brayn /, adj. having, involving, or pertaining to a severed corpus callosum. [1955 60] * * * … Universalium
Split Brain (Informatik) — Split Brain ist in der Informatik ein unerwünschter Zustand eines Computerclusters, bei dem alle Zwischenverbindungen zwischen den Clusterteilen gleichzeitig unterbrochen sind. Inhaltsverzeichnis 1 Formen 2 Zustandekommen 3 Auswirkungen … Deutsch Wikipedia