The effects of stroke vary from person to person. They are based on the type, severity, location, and number of strokes. The brain is very complex. Each part of the brain has a certain function or ability. When an area of the brain is damaged from a stroke, the part of the body it controls may lose normal function. This may result in a disability. Large strokes can cause death. Smaller strokes in certain parts of the brain can also cause death.
The effects of a stroke depend on where it occurs. The brain has 3 main areas:
Cerebrum. This is the name for the right and left sides of the brain. The sides are also called hemispheres.
Cerebellum. This is the back of the brain.
Brainstem. This is the base of the brain.
The cerebrum controls:
Movement and feeling
The cerebrum is divided into the right and left sides. The sides are called hemispheres. For most feeling and movement, 1 side of the cerebrum controls the opposite side of the body. For example, the right side of the cerebrum controls some functions on the left side of the body. Depending on the area and side of the cerebrum affected by the stroke, any of these functions may be impaired:
Speech and language
Chewing and swallowing
Cognitive ability, such as thinking, reasoning, judgment, and memory
Awareness of surroundings
Bowel and bladder control
In addition to these effects, some specific changes may occur if certain parts of the cerebrum are damaged.
The effects of a right hemisphere stroke may include:
Left-sided weakness or paralysis and sensory loss
Ignoring paralysis or other problems created by the stroke (this is called "left neglect")
Vision problems, including loss of the left field of vision in both eyes
Problems with depth perception or directions, such as up or down and front or back
Not able to locate or recognize body parts
Not able to understand maps or find objects, such as clothing or personal items
Behavior changes, such as lack of concern, impulsivity, and inappropriate words or actions
The effects of a left hemisphere stroke may include:
Right-sided weakness or paralysis and sensory loss
Problems with speech and understanding language (aphasia)
Vision problems, including the loss of the right field of vision in both eyes
Not as able to do math, or to organize, reason, or analyze
Behavior changes, such as being cautious and hesitant
Impaired ability to read, write, and learn new information
The cerebellum is beneath and behind the cerebrum. It is at the back of the brain. It gets sensory information from the body through the spinal cord. It helps manage muscle action and control. It controls fine movement, coordination, and balance.
Strokes are less common in the cerebellum area. But the effects can be severe. The common effects of strokes in the cerebellum include:
Being unable to walk
Trouble with coordination and balance (ataxia)
Nausea and vomiting
The brainstem is at the base of the brain. It is right above the spinal cord. Many of the body's vital "life-support" functions are controlled by the brainstem. These include heartbeat, blood pressure, and breathing. It also helps control the main nerves for eye movement, hearing, speech, chewing, and swallowing. Some common effects of a stroke in the brainstem include:
Breathing and heart function problems
Trouble with body temperature control
Balance and coordination problems
Weakness or paralysis
Trouble chewing, swallowing, and speaking