Brain lesions are areas of damaged brain tissue. This kind of damage happens because of brain injuries or medical conditions. A stroke, for example, is a type of brain lesion. Lesions can disrupt the way your brain works, causing a wide range of symptoms, such as weakness, disruption of one or more senses and confusion.
When it comes to your brain, communication is everything. Your brain uses electrical and chemical signals to communicate inside your brain itself and with areas throughout your body. When you have a brain lesion, the damage can disrupt communication in the affected brain area(s). The more severe the damage, the greater the disruption.
Different areas of your brain control different processes and functions, so the symptoms of brain lesions vary depending on their location. A neurologist or other healthcare provider uses your symptoms to locate where the problem is within your brain. The three main areas of the brain are the cerebrum, cerebellum and brainstem.
Your cerebrum is the main part of your brain. It has two halves: the left hemisphere and the right hemisphere.
Both hemispheres of your brain have four areas known as lobes. They’re the frontal, temporal, parietal and occipital lobes. There’s also a hidden internal area called the insula, underneath the frontal lobe.
|Lobe and its location||Possible conditions and symptoms with lesions in this lobe|
|Frontal: Front of your head.||Trouble with learning.|
Executive dysfunction and problems with attention (planning, focusing and inhibition).
Agitation and mood swings.
Aphasia (Broca’s subtype): Trouble getting words out.
Weakness or paralysis in a specific area or side of your body.
Loss of sense of smell (anosmia).
|Temporal: Sides of your head.||Aphasia (Wernicke’s subtype): Trouble understanding words.|
Auditory processing difficulties.
|Parietal: Top of your head.||Numbness or tingling (although this usually isn’t from your brain, and from the nerves in your limbs).|
Agraphia (inability to write).
Acalculia (inability to do math).
Finger agnosia (inability to recognize your own hands and fingers).
Confusion of left and right.
|Insular: Underneath frontal, parietal and temporal lobes.||Loss of sense of taste (ageusia).|
Disruptions of the sympathetic (fight or flight) nervous system and the parasympathetic (rest and digest) nervous system.
|Occipital: Back of your head.||Cortical blindness (loss of vision because of a problem with your brain rather than your eyes).|
Total color blindness (achromatopsia).
Face blindness (prosopagnosia).
Issues with recognizing things you see (visual agnosia).
Your cerebellum is a densely packed area of brain tissue at the bottom rear of your skull. Symptoms of lesions in your cerebellum include:
Your brainstem is a stalk-like structure that connects your brain to your spinal cord. Lesions on your brainstem can cause problems with your heart rhythm, breathing, blood pressure, eye alignment and more.
Brain lesions can happen with any condition or circumstance that can damage your brain.
Medical conditions that can cause brain lesions include:
Injury, trauma and nonmedical circumstances that can cause brain lesions include:
A healthcare provider might start to suspect a lesion following a neurological exam. In this exam, a healthcare provider tests muscle strength in your limbs, checks your reflexes and determines if your senses work correctly.
After a neurologic exam, the next step to detect a brain lesion is with imaging scans. Some of the most common imaging technologies that can show these kinds of lesions include:
Other tests are also possible, but these are typically used to detect or rule out another condition that could cause similar symptoms. Your healthcare provider is the best person to tell you what tests they recommend and why.
Brain lesions can happen for many reasons, which means there are many ways to treat them. Your provider will base their treatment recommendations on the underlying cause of your brain lesion.
Some conditions that cause brain lesions, like a mild concussion, go away on their own. If the lesion isn’t severe, treatments are unnecessary. Rest and reduced activity are often all that you’ll need.
Other conditions that cause brain lesions are treatable in different ways. Infections are often treatable with antibiotics or supportive care. Growths or tumors — especially easy-to-reach ones — may be removable with surgery. Some lesions are very small and don’t cause symptoms or harm.
Unfortunately, there are also times when brain lesions aren’t treatable. This is most likely with lesions that cause severe damage. The same is true for incurable conditions like Alzheimer’s disease.
Because the treatment options can vary, your healthcare provider is the best person to tell you which one(s) they recommend and why.
Brain lesions are sometimes preventable, depending on the cause. The types of lesions that are most preventable are those that happen because of concussions and traumatic brain injuries. Treating infections in your body promptly can also prevent an infection from spreading to your brain and causing damage.
Some of the most helpful things you can do to prevent brain lesions, or at least reduce your risk of developing them, include:
Brain lesions can indicate you have a severe or even life-threatening issue. For example, a stroke is a time-sensitive medical emergency. If you think someone with you is having a stroke, call 911 or your local emergency services number.
Other symptoms of brain lesions that mean you need medical attention quickly include:
A note from Cleveland Clinic
Brain lesions can happen for many reasons, making them a very common sign of a brain-related condition. Some lesions are minor and need little or no treatment to heal. Others are more severe and may need medical care, such as surgery. Unfortunately, some lesions are severe, permanent or happen for reasons that aren’t treatable.
Advances in medical imaging mean healthcare providers are better able to detect and analyze brain lesions. These imaging technologies are also key in planning out possible treatments and predicting your case’s possible or likely outcomes. Advances in medicine’s understanding of the brain also offer new possibilities for treatment or recovery from brain lesions and the conditions that cause them.
Last reviewed by a Cleveland Clinic medical professional on 11/16/2022.