WEBVTT

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Each hemisphere receives information primarily from the opposite side of the body.

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That is, information from the right hand goes to the left hemisphere and vice versa.

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This is called contralateral innervation.

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The two hemispheres are interconnected by sets of bands.

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The largest is called the corpus callosum.

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For medical reasons, the corpus callosum has been cut in some people.  We call them “split-brain” patients.

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Tests with these patients have revealed that the two hemispheres of the brain have unique abilities.

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The left hemisphere is better at language.

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If a right-handed split brain patient holds an object in their left hand, the information goes to the right hemisphere and

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usually, the split-brain patient will not know what the object is.

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If the object is placed in the right hand, the information goes to the left hemisphere

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and the patient has no problem naming the object.

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The right hemisphere is very good at spatial tasks.

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If the split-brain patient has to solve a simple puzzle with their right hand

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the information goes to the left hemisphere and they will usually fail.

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If the split-brain patient is allowed to use their left hand

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the information goes directly to the right hemisphere and they will succeed.

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People with an intact corpus callosum do not have these problems because information

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can be transferred from one hemisphere to the other via the corpus callosum.

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These differences in abilities of the two hemispheres is called hemispheric specialization.