Stroke can affect people in different ways. It depends on the type of stroke, the area of the brain affected and the extent of the brain injury. Brain injury from a stroke can affect the senses, motor activity, speech and the ability to understand speech. It can also affect behavioral and thought patterns, memory and emotions. Paralysis or weakness on one side of the body is common.

Most of these problems can improve over time. In some patients they will go away completely.

How can a stroke affect emotions?

Some areas of the brain produce emotions, just as other parts produce movement or allow us to see, hear, smell or taste. If these areas are injured by a stroke, a survivor may cry easily or have sudden mood swings, often for no apparent reason. This is called emotional lability. Laughing uncontrollably also may occur but isn't as common as crying. Depression is common as stroke survivors recover and as they come to terms with any impairment that doesn't fully go away.

How can a stroke cause loss of awareness?

Stroke often causes people to lose mobility and/or feeling in an arm and/or leg. If this affects the left side of the body (caused by a stroke on the right side of the brain), stroke survivors may also forget or ignore their weaker side. This problem is called neglect. As a result, they may ignore items on their affected side and not think that their left arm or leg belongs to them. They also may dress only one side of their bodies and think they're fully dressed. Bumping into furniture or door jambs is also common.

How can a stroke affect perception?

A stroke can also affect seeing, touching, moving and thinking, so a person's perception of everyday objects may be changed. Stroke survivors may not be able to recognize and understand familiar objects the way they did before. When vision is affected, objects may look closer or farther away than they really are. This causes survivors to have spills at the table or collisions or falls when they walk.

How can a stroke affect hearing and speech?

Stroke usually doesn't cause hearing loss, but people may have problems understanding speech. They also may have trouble saying what they're thinking. This is called aphasia. Aphasia affects the ability to talk, listen, read and write. It's most common with a stroke on the left side of the brain, which may also weaken the body's right side.

A related problem is that a stroke can affect muscles used in talking (those in the tongue, palate and lips). Speech can be slowed, slurred or distorted, so stroke survivors can be hard to understand. This is called dysarthria. It may require the help of a speech expert.

How can a stroke affect chewing and swallowing food?

The problem with chewing and swallowing food is called dysphagia. It can occur when muscles on one side of the mouth are weak. One or both sides of the mouth can also lack feeling, increasing the risk of choking.

How can a stroke affect the ability to think clearly?

Parts of the brain allow us to form long-term and short-term memories. (Short-term memories help us remember why we got up and walked into the next room, for example.) With injury to these areas, it may be hard to plan and carry out even simple activities. Stroke survivors may not know how to start a task, confuse the sequence of logical steps in tasks, or forget how to do tasks they've done many times before.

It's important for stroke survivors to receive appropriate rehabilitation to help alleviate these deficits.

For stroke information, call the American Stroke Association at 1-888-4-STROKE.

Related AHA and ASA publications:

• Know the Facts, Get the Stats... heart disease, stroke and risks
• Understanding Stroke (also in Spanish)
• Warning Signs of Stroke (Quick and Easy Reading) (also in Spanish)
• Caring for Someone With Aphasia 
• How Stroke Affects Behavior 
• Living With Disability After Stroke 
• Being a Stroke Family Caregiver 
• Sex After Stroke
• American Heart Association Family Guide to Stroke: Treatment, Recovery, and Prevention (available where books are sold)
• Take Charge Against Stroke... Our guide for women
• We're Talking About Women and Stroke (Quick and Easy Reading) (also in Spanish)
• Sheets from Let's Talk About Stroke kit

• Resources for explaining changes after a stroke 
• Introductory information for stroke families 
• Resources for stroke family caregivers 
• Resources for communication challenges after a stroke