An Overview of Stroke

In This Article

Table of Contents

A stroke happens when there is an interruption of blood flow to a region of the brain that causes brain damage. This can result in diminished physical function, impaired thinking skills, or both, and the level to which this occurs varies depending on what part of the brain is injured and the extent of the damage. The effects of a stroke can be quite serious, but they can also be far less impactful.

Strokes are treatable, so it is important to be able to recognize a stroke when one occurs so that you can get the right emergency treatment

Each year, approximately 800,000 Americans have a stroke. Unlike heart attacks, which are painful events, strokes are not usually painful.


Recognizing the symptoms of a stroke can save a life. You can use the acronym FAST to remember them and the important step to take if you notice them:

  • Facial drooping
  • Arm weakness
  • Speech difficulties
  • Time to call emergency services

Additional stroke symptoms include:

  • Body weakness
  • Facial weakness
  • Speech changes
  • Vision changes
  • Falling
  • Sensory abnormalities
  • Headaches or dizziness
  • Confusion

Time spent deciding whether or not to obtain medical attention could end up as time that could and should have been spent getting medical treatment.


The causes of stroke are well known and mostly preventable or controllable lifestyle factors or medical conditions. Risk factors include:

  • Heart disease, cerebrovascular disease, and carotid artery disease
  • Hypertension and malignant hypertension
  • High cholesterol, fat, and triglyceride levels
  • Diabetes
  • Blood disorders and infections
  • Autoimmune or severe systemic disease
  • Smoking
  • Obesity
  • Sedentary lifestyle
  • Excessive stress
  • Drugs

Stroke prevention requires adjustment of lifestyle habits, as well as good medical care aimed at detecting and regulating the health conditions that are known to lead to stroke.

Brain injury from stroke is the result of a series of biological events that occur when there is a lack of sufficient blood supply to a region of the brain. Blood flow to the brain is vitally important because blood contains the oxygen and nutrients necessary for each and every brain cell to function normally.

Even a few minutes of interrupted blood flow is enough to cause brain damage.


If you or someone you know experiences any of the symptoms of stroke, it is important to get professional medical attention immediately. Though stroke severity can vary, it is one of the leading causes of death and disability.

Prompt medical care is the best way to prevent the worst and reduce the level of disability for the majority of stroke survivors.

There are two main types of strokes—ischemic and hemorrhagic—which are differentiated by the type of blood vessel problem that has occurred.

Ischemic strokes are caused by blockage of one of the cerebral blood vessels. These can be:

  • Thrombotic, when there is a formation of a thrombus (clot) directly inside the blood vessel
  • Embolic, when the blood clot originates in other areas of the body, such as the heart, and travels to the brain causing a blockage of one of its vessels

Hemorrhagic strokes are strokes caused by a blood vessel rupture and characterized by bleeding in the brain. Hemorrhagic strokes are sub-divided into two types:

Furthermore, there are three major categories of stroke, which are differentiated based on which region of the brain is affected.

  • Cortical stroke (large vessel stroke): A stroke that affects the cerebral cortex is defined as a cortical stroke or a large vessel stroke. This type causes deficits in reasoning, thinking, language, memory, movement, sensation, or vision.
  • Subcortical stroke (small vessel stroke): A stroke in the subcortical region of the brain is called a small vessel stroke. This type of stroke may cause memory deficits, weakness, tingling, or sensory loss.
  • Brainstem stroke: A brainstem stroke may cause double vision, dizziness, swallowing problems, breathing problems, or hiccups, as well as tingling or numbness.

Telltale Signs

Certain arteries are dedicated to providing blood to defined regions of the brain—each of which control specific functions. This mapping is quite consistent from person to person. As such, the effects of a stroke can reveal what part of the brain was affected, as well as which blood vessel was interrupted. For example, weakness indicates a stroke in the motor area of the brain. Identifying this is one of the ways that your healthcare team can effectively care for you if you ever experience a stroke.


Stroke is treatable in the first few hours after stroke symptoms begin. Emergency stroke treatment requires a trained medical team that can act quickly to administer powerful medications that can reduce or reverse the obstruction of blood flow before it causes permanent brain damage.

Emergency treatment such as tissue plasminogen activator (TPA) and intra-arterial thrombolysis are becoming available in more medical centers as technology advances. Even mobile stroke units are making stroke care faster and more accessible.

Stroke assessment is based on the National Institutes of Health Stroke Scale (NIHSS), a systematic assessment tool that provides a quantitative measure of stroke-related neurologic deficit.

Once stroke damage has occurred, there is no known medical or surgical treatment that can repair the brain. That is why stroke prevention and emergency treatment are so important.

Stroke recovery is about maintaining optimal health to allow the brain to recover on its own, and then ‘watching and waiting’ as recovery and healing take place.

Rehab and Recovery

Many stroke patients undergo physical or occupational therapy to regain skills they may have lost as a result of the damage caused by stroke.

Long-term effects of a stroke that may be focussed on in the recovery period include, but are not limited to:

  • Weakness of or loss of sensation on one side of the body or the face
  • Slurred speech
  • Balance problems
  • Difficulty with problem solving

A Word From Verywell

Recognizing stroke symptoms is the key to getting the care you or someone else needs, as time is of the essence when stroke strikes. Unfortunately, many don't know much about stroke until they or a loved one is diagnosed with one. If that's your situation, learn as much as you can prepare for what's ahead. If the impact of a stroke is profound, know that life can improve. Though it may very well be that things won't be the same as before, rehabilitation and recovery can help one face the future with greater confidence.

Was this page helpful?

Article Sources

  1. Aroor S, Singh R, Goldstein LB. BE-FAST (Balance, Eyes, Face, Arm, Speech, Time): Reducing the Proportion of Strokes Missed Using the FAST Mnemonic. Stroke. doi: 10.1161/STROKEAHA.116.015169

  2. Feigin VL, Nguyen G, Cercy K, et al. Global, Regional, and Country-Specific Lifetime Risks of Stroke, 1990 and 2016. N Engl J Med. doi: 10.1056/NEJMoa1804492

  3. Centers for Disease Control and Prevention. Stroke, Updated May 2019.

  4. Leisman G, Moustafa AA, Shafir T. Thinking, Walking, Talking: Integratory Motor and Cognitive Brain FunctionFront Public Health. doi:10.3389/fpubh.2016.00094

  5. Merwick Á, Werring D. Posterior circulation ischaemic stroke. BMJ. doi: 10.1136/bmj.g3175

  6. Fu X, Lu Z, Wang Y, et al. A Clinical Research Study of Cognitive Dysfunction and Affective Impairment after Isolated Brainstem StrokeFront Aging Neurosci. doi:10.3389/fnagi.2017.00400

  7. Hacke W. A New DAWN for Imaging-Based Selection in the Treatment of Acute Stroke. N Engl J Med. doi:10.1056/NEJMe1713367

Additional Reading