right hemisphere of the brain controls the movement of the left side of the body.
It also controls analytical and perceptual tasks, such as judging distance, size,
speed, or position and seeing how parts are connected to wholes. A stroke in the
right hemisphere often causes paralysis in the left side of the body. This is
known as left hemiplegia.
right-hemisphere strokes may also have problems with their spatial and perceptual
abilities. This may cause them to misjudge distances (leading to a fall) or be
unable to guide their hands to pick up an object, button a shirt or tie their
shoes. They may even be unable to tell right-side up from upside-down when trying
to read. Along with their impaired ability to judge spatial relationships, survivors
of right-hemisphere strokes often have judgment difficulties that show up in their
behavioral styles. These patients often develop an impulsive style unaware of
their impairments and certain of their ability to perform the same tasks as before
the stroke. This behavioral style can be extremely dangerous. It may lead the
left hemiplegic stroke survivor to try to walk without aid. Or it may lead the
survivor with spatial and perceptual impairments to try to drive a car.
Survivors of right-hemisphere strokes may also experience left-sided neglect.
Stemming from visual field impairments, left-sided neglect causes the survivor
of a right-hemisphere stroke to "forget" or "ignore" objects or people on their
left side. Finally, some survivors of right-hemisphere strokes will experience
problems with short-term memory. Although they may be able to recount a visit
to the seashore that took place 30 years ago, they may be unable to remember what
they ate for breakfast that morning.
The left hemisphere of the brain controls the movement of the right side
of the body. It also controls speech and language abilities for most people. A
left-hemisphere stroke often causes paralysis of the right side of the body. This
is known as right hemiplegia. Someone who has had a left-hemisphere stroke may
also develop aphasia. Aphasia is a catch-all term used to describe a wide range
of speech and language problems. These problems can be highly specific, affecting
only one component of the patient's ability to communicate, such as the ability
to move their speech-related muscles to talk properly. The same patient may be
completely unimpaired when it comes to writing, reading or understanding speech.
In contrast to survivors of right-hemisphere stroke, patients who have had a left-hemisphere
stroke often develop a slow and cautious behavioral style. They may need frequent
instruction and feedback to complete tasks. Finally, patients with left-hemisphere
stroke may develop memory problems similar to those of right-hemisphere stroke
survivors. These problems can include shortened retention spans, difficulty in
learning new information and problems in conceptualizing and generalizing.
The cerebellum controls many of our reflexes and much of our balance and
coordination. A stroke that takes place in the cerebellum can cause abnormal reflexes
of the head and torso, coordination and balance problems, dizziness, nausea and
Strokes that occur in the brain stem are especially devastating. The
brain stem is the area of the brain that controls all of our involuntary, "life-support"
functions, such as breathing rate, blood pressure and heartbeat. The brain stem
also controls abilities such as eye movements, hearing, speech and swallowing.
Since impulses generated in the brain's hemispheres must travel through the brain
stem on their way to the arms and legs, patients with a brain stem stroke may
also develop paralysis in one or both sides of the body.
strokes are associated with atherosclerosis,
high blood pressure, oxygen damage or a combination
of the three.
Stroke Support Groups