Heterotopia has two main definitions in the field of medicine.
The first definition is an abnormal condition in which an organ
or part of the body is out of its normal place. A good example
is heterotopic ossification, which is an abnormal formation of
bone in soft tissue. Heterotopia may be congenital (present
since birth) or it may be acquired during some other point in
life. This definition of heterotopia is also known as ectopia
and ectopy.

In the study of diseases of the nervous system, heterotopia
refers to when gray matter in the brain is out of its normal
place and has typically made its way into the white matter of
the cerebrum, where it should not be.
Heterotopia of the elbow.
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Gray matter is gray appearing tissue in the brain composed of cell bodies that play an
important role in thinking, sensory control, movements, and emotional processing. White
matter is a group of white nerve fibers that conduct nerve impulses quickly. The cerebrum
is the top section of the brain which contains four lobes. Heterotopic and heterotpous
means pertaining to heterotopia.

Heterotopia comes from the Greek word "heteros" meaning "other," and the Greek word
"topos" meaning "place." When you put the two words together the translation is "other
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