Final answer:
Holoprosencephaly, characterized by the incomplete separation of cerebral hemispheres, is indeed due to the failure of the left and right hemispheres to separate. In contrast, 'split-brain' refers to a surgically induced condition in which the corpus callosum is cut to treat severe epilepsy, manifesting different symptoms and insights into brain hemisphere functions.
Step-by-step explanation:
The statement 'Holoprosencephaly is due to failure of the left and right hemispheres to separate' is true. Holoprosencephaly is a congenital brain development disorder characterized by the incomplete separation of the two cerebral hemispheres. This condition differs from a split-brain situation which arises when the corpus callosum, the major connection between the two hemispheres, is cut, usually in an attempt to treat severe epilepsy. Holoprosencephaly is a distinct developmental condition, while split-brain results from surgical intervention intended to reduce epilepsy symptoms. Split-brain patients, post-surgery, may exhibit behaviors that indicate specialized functions of each hemisphere; for instance, they might be unable to name objects that are processed by the right hemisphere since the left hemisphere, generally responsible for language, does not receive the information due to the severed corpus callosum.
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