Migraine, particularly migraine with aura, can cause transient global amnesia, a sudden and brief loss of memory. For many people with migraine, particularly children and younger adults, research suggests that brain fog and temporary memory loss can occur before, during, or after a migraine attack and even in between attacks, the American Migraine Foundation (AMF) notes. In addition, a rare form of migraine, hemiplegic migraine, may cause more lasting brain function problems, including long-term memory loss, according to the National Organization for Rare Disorders (NORD). The symptoms of hemiplegic migraine resemble a stroke; people who have it experience weakness on one side of their body (hemiplegia) along with headache and other symptoms seen in migraine, the AMF says. “Migraine is a disabling disease, and it’s disabling in many ways and because of many factors,” notes Olivia Begasse de Dhaem, MD, a neurologist and headache medicine specialist at Hartford Healthcare in Connecticut. “Cognitive dysfunction, or the inability to think or concentrate, is a common and disabling symptom of migraine attacks. Studies have shown that people under 50 years old who have migraine have worse performance in terms of attention and memory than people without migraine, even when tested outside of their migraine attacks,” says Dr. Begasse de Dhaem.

How Does Migraine Affect Thinking and Memory?

Although most people with migraine don’t experience memory loss, about 40 percent of those who have it do experience cognitive impairment, including declines in attention, processing speed, and memory, according to a study published in 2021 in The Journal of Headache and Pain. In general, problems with focus and memory are more common in those with chronic migraine than in those with episodic migraine, a study published in 2020 in the Brazilian medical journal Arquivos de Neuro-Psiquiatria found. In the study, nearly two-thirds of people with chronic migraine experienced memory problems, and they were up to four times more likely than those with episodic migraine to do so. Chronic migraine is defined as having at least 15 headache days a month, with at least eight of those headaches having migraine features, for more than three months, according to the Cleveland Clinic. Still, the links between certain types of migraine and memory loss continue to be evaluated in research studies, and those relationships may become clearer as our understanding of the genetics behind migraine grows, Begasse de Dhaem says. In addition, “we don’t have enough data to make statements regarding memory loss and migraine frequency, duration, and presence of aura,” she adds.

Why Does Migraine Cause Memory Problems?

Memory problems can occur at any time during a migraine, according to the AMF. When your migraine attack begins, you may experience feelings of haziness, or brain fog, that can last for a few hours or even a few days, the organization says. However, those symptoms usually develop about two days before the pain symptoms and last until a day after the pain resolves. Because of that time line, brain fog may be a warning sign of migraine attack onset, the AMF notes. If you develop brain fog, you may have difficulty focusing or finding the right words. You may also feel distracted, forgetful, less alert, or have trouble completing simple day-to-day tasks. In most cases, the memory loss problems associated with chronic or episodic migraine are short-term, and they are usually the result of problems with attention caused by the disorder, Begasse de Dhaem says. “If someone isn’t able to pay attention or concentrate and then doesn’t recall the information they learned, it’s not that they forgot or experienced memory loss; it’s that they had difficulty paying attention,” she adds.

What Causes Memory Loss With Migraine?

Although researchers are still learning what causes brain fog in people with migraine, it’s thought that migraine affects how the brain perceives and processes information — in several ways. For example, the complication may be linked with the “cortical depression” that occurs in the brain before a migraine attack, according to the AMF. Cortical depression is an electrical and blood flow process that typically spreads from the back of the brain, the region that controls your vision, to the front of the brain, which governs thinking and memory. As the cortical depression shifts in your brain before a migraine attack, it can slow your thinking processes, the AMF says. That also explains why some people also have aura, or visual disturbances, before their headache phase, the organization adds. That said, the effects of migraine on the brain are usually temporary: Migraine doesn’t cause permanent brain damage or destroy brain cells, according to the AMF. Even so, you may have difficulty thinking clearly or focusing on tasks after a migraine, during what’s called the postdrome phase (sometimes called a migraine hangover). However, once the cortical depression has passed, the brain fog will resolve, usually within a few days of the aura phase, Begasse de Dhaem says. People with migraine may have changes in the white matter of their brain, which is the region the brain uses to communicate with the rest of the central nervous system. Those changes, which appear in the form of little dots on a magnetic resonance imaging scan, don’t impact cognitive function, according to Begasse de Dhaem.

Medications May Play a Role in Migraine Memory Problems

Another potential cause of brain fog and the related memory problems associated with migraine may be the prescription medications people take to prevent the attacks, according to the AMF. Some of those medications may affect brain function, causing short-term drowsiness or confusion. Examples include:

TopiramateAmitriptylineNortriptylinePromethazineMetoclopramideProchlorperazine

If you experience brain fog or confusion while taking any of these medications, talk to your doctor. But don’t stop the treatments on your own, Begasse de Dhaem advises.

Memory loss due to hemiplegic migraine may be more prolonged, according to NORD. That is because the condition is caused by proteins that form in the brain and prevent nerve cells from functioning normally, the organization says. However, experiencing short- or long-term memory problems due to migraine does not necessarily affect your risk of dementia later in life, according to Begasse de Dhaem. “Reassuringly, there doesn’t seem to be an association between migraine and memory loss later in life, nor dementia,” she says. Indeed, the results of a study published in 2020 in Headache found no association between a history of migraine and dementia in a group of nearly 12,500 Americans ages 51 to 70 who were followed by researchers for about 20 years.