Strokes occur when there’s a disruption to blood flow to part of your brain. The three main types of strokes cause this disruption in different ways. But doctors can also classify stroke according to its location.

A stroke is a medical emergency. It happens when blood flow to part of your brain is interrupted. Without blood, your brain cells start to die. This can cause serious symptoms, lasting disability, and even death.

There are several kinds of strokes. Keep reading to learn about the three main types of strokes, their subtypes, and other ways doctors may classify strokes.

What are the 3 main types of strokes?

The three main types of strokes are:

  • Transient ischemic attack (TIA): a temporary blockage of blood flow to part of your brain
  • Ischemic stroke: a blood clot blocks blood flow to part of your brain
  • Hemorrhagic stroke: a blood vessel in your brain ruptures or breaks, spilling blood into the surrounding tissues

Also known as a ministroke, a TIA is a temporary blockage of blood flow to part of your brain. The blood clot and TIA symptoms last for a short time without causing long-term damage.

A TIA can be a warning and increases your risk of a future stroke. Treating a TIA involves taking steps to prevent a future stroke, including medications and lifestyle changes.

An ischemic stroke occurs when a blood clot blocks blood flow to part of your brain. The blood clot is often due to atherosclerosis, a buildup of fatty deposits on the inner lining of a blood vessel.

The disease process is similar to a heart attack, where a blood clot blocks blood flow to a portion of your heart.

Unlike a TIA, the blood clot that causes an ischemic stroke won’t go away without treatment.

Ischemic strokes are the most common type of stroke. Older U.S. data suggests that ischemic strokes make up 87% of strokes, but recent global data from 2019 says they make up 62.4%.

Types of ischemic stroke: Thrombotic vs. embolic strokes

Doctors can classify ischemic strokes based on what causes the blockage:

  • Thrombotic stroke: A thrombotic stroke is an ischemic stroke due to a clot forming in a blood vessel in your brain. It’s the most common cause of ischemic strokes.
  • Embolic stroke: In an embolic stroke, the blood clot has traveled from another part of your body to your brain. These clots most often travel from the heart (cardioembolic strokes). A heart condition called atrial fibrillation is the most common underlying cause of embolic stroke.

Types of ischemic stroke: Lacunar vs. LVO strokes

Doctors can also classify ischemic strokes based on the size and location of the blood vessels involved:

  • Lacunar stroke: Lacunar strokes affect the small blood vessels deep within your brain. They account for 15% to 25% of all ischemic strokes. Lacunar strokes are usually thrombotic and not embolic because tiny blood vessels can become blocked due to atherosclerosis. They can often go unnoticed without symptoms, but multiple lacunar strokes can lead to serious complications.
  • Large vessel occlusion (LVO) strokes: LVO strokes affect the larger arteries within the brain. They make up 24% to 46% of ischemic strokes and are more severe than lacunar strokes. They’re usually embolic.

A hemorrhagic stroke occurs when a blood vessel in your brain ruptures or breaks, spilling blood into the surrounding tissues. This can be due to:

  • an aneurysm causing a portion of the weakened blood vessel to balloon outward and sometimes rupture
  • an arteriovenous malformation, which is a structural problem typically present from birth
  • very high blood pressure causing a tear in a weakened blood vessel in your brain
  • hemorrhagic transformation, which is when an ischemic stroke causes bleeding

Types of hemorrhagic stroke: ICH vs. SAH

Doctors can classify hemorrhagic stroke based on where the rupture occurs — specifically, whether it happens in a blood vessel in the brain or on the surface of the brain:

  • Intracerebral hemorrhage (ICH): An ICH occurs when a blood vessel in the brain bursts. ICHs account for about three-quarters of hemorrhagic strokes, according to 2019 data.
  • Subarachnoid hemorrhage (SAH): An SAH involves the rupture of a blood vessel in the subarachnoid space (a layer surrounding the brain).

Your brain has two hemispheres (sides): a left and a right. The left side of your brain controls the right side of your body, while the right side of your brain controls the left side of your body.

This means a stroke on the left side of your brain may cause physical symptoms on the right side of your body and vice versa. But there may be other differences, as noted in the table below:

Left side stroke symptomsRight side stroke symptoms
weakness or paralysis on right sideweakness or paralysis on left side
diminished sensation on right sidediminished sensation on left side
vision loss of right visual field of both eyesvision loss of left visual field of both eyes
difficulty with calculations or problem-solvingdifficulty with abstract and spatial thinking
difficulties with speech and languageunawareness of neurological issues

Scientists have traditionally divided each side of the cerebral cortex (the outer layer and largest region of your brain) into four lobes.

The lobes have different functions, so strokes in a specific lobe may lead to specific symptoms or complications. For example:

  • Frontal lobe stroke: The frontal lobe in your brain is responsible for numerous functions, including memory, speech, personality, and movement. As the largest lobe, it’s commonly involved in strokes.
  • Temporal lobe stroke: The temporal lobe sits beneath the parietal lobe. It’s important for short-term memory, hearing, and speech. A stroke here can lead to aphasia, a communication disorder.
  • Parietal lobe stroke: The parietal lobe at the top middle of your brain is vital in processing sensory information and language. Parietal lobe strokes often cause paresthesia (numbness and tingling) and aphasia.
  • Occipital lobe stroke: The occipital lobe at the back of your brain is responsible for visual processing. Occipital strokes cause changes in vision, such as blurriness, visual hallucinations, or cortical blindness.

Strokes can also affect several structures below the cerebral cortex. These are known as subcortical strokes. For example:

  • Basal ganglia stroke: The basal ganglia is a group of neurons deep in the brain responsible for movement, reward, and cognition. Strokes here have outcomes similar to strokes in other regions but carry an increased risk of bleeding complications during treatment and future risk of Parkinsonism.
  • Brain stem stroke: About 11% of ischemic strokes and 5% to 13.4% of hemorrhagic strokes affect the brain stem, just above your spinal cord. The brain stem is responsible for vital functions like breathing, heart rate, and blood pressure. Scientists consider brain stem strokes the most lethal type of stroke.
  • Thalamic stroke: Thalamic strokes are a type of lacunar stroke affecting the thalamus near the center of your brain. Your thalamus is involved in sensation, sleep, consciousness, and memory. A 2024 study found that rapid recovery and excellent long-term outcomes were common after thalamic stroke.
  • Cerebellar stroke: A cerebellar stroke affects the cerebellum in the back of your brain, which controls movement and balance. People can sometimes mistake cerebellar strokes for vertigo, but cerebellar strokes can become serious without prompt treatment.

Doctors may also refer to strokes by which arteries are involved:

  • Middle cerebral artery (MCA) stroke: The MCA is the most common artery involved in stroke. Since it supplies blood to the frontal, temporal, and parietal lobes, it can cause many symptoms. Other than brain stem strokes, MCA strokes are the most unpredictable and require aggressive treatment.
  • Anterior cerebral artery (ACA) stroke: ACA strokes are rare and typically have a favorable outcome. They affect only the frontal lobe. Distinctive symptoms may include aphasia, behavior changes, and urinary incontinence.
  • Posterior cerebral artery (PCA) stroke: PCA strokes are challenging to diagnose since they cause an inconsistent and wide variety of nonspecific symptoms. They can affect the occipital lobe and brain stem. When strokes begin in the deep regions of the PCA, outcomes are typically less favorable.

Stroke treatment depends on many factors, including the type of stroke and how long it lasts. The sooner you can receive a diagnosis and treatment, the more likely you’ll have a better recovery.

Treatment for ischemic strokes, regardless of subtype, involves removing the blood clot. This usually requires medication but may also require surgery.

Hemorrhagic stroke treatments involve trying to stop bleeding in your brain and reduce the side effects associated with brain bleeding. Surgical procedures include clipping or coiling, which aim to prevent further bleeding.

Surgical options often depend on the location of the stroke and how easy it is for the surgical team to reach it.

Doctors classify strokes as either ischemic (due to a blockage) or hemorrhagic (due to bleeding). A TIA, or ministroke, is due to a temporary blockage that doesn’t cause long-term damage.

But doctors may refer to subtypes of strokes based on:

  • what causes the blockage or bleeding, such as thrombotic or embolic strokes
  • the region or lobe of the brain, such as brain stem strokes or occipital lobe strokes
  • the blood vessels involved, such as MCA, ACA, or PCA strokes

This information can provide insight into what symptoms to expect, how to manage the stroke, and what to expect from recovery. Talk with your doctor about how your stroke type influences your treatment and outlook.