What happens during a Stroke?

The authors above have described the stroke.  The effects
of a stroke can be mild, severe, or fatal; if the person survives, he can show mild to
severe disability, or perhaps none at all.

A stroke can
occur anywhere in the brain, so any bodily function can be affected by the death of the
part of the brain responsible for it.  For instance, one entire side of the body can be
completely or partly paralyzed, while the rest of the body is healthy.  Or, the person's
speech can be damaged -- in a variety of ways -- while his movement is unimpaired.
 Similarly for vision: the sight of one eye can be destroyed, or the ability to
recognize an object (for example, to read) can be
damaged.

Often, a stroke can damage areas of the brain
responsible for cognition,  The person might be unable to talk, or unable to understand
speech, or unable to recognize faces, or unable to remember the names of
things.

Psychologists and neurologists can (and do) use
strokes as "probes" of how the brain functions.  If a person is unable to recognize
faces, but is otherwise healthy, and if the location of the damaged brain tissue can be
determined, the investigator can infer that that specific area of the brain is involved
in that specific part of cognition.

Sometimes the
neurological damage done by a stroke can be ameliorated using "neural plasticity":  the
ability of the nervous system to find a way around a difficulty.  This requires a good
therapist, a lot of practice by the person, and a great deal of
patience.

For more information, you might see the reference
below.