Your Brain on Migraines

Medically Reviewed By William C. Lloyd III, MD, FACS
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If you have migraines, you might have experienced what some people describe as “brain fog.”

When you’re having a migraine attack, you may suspect you’re not thinking or talking as clearly as you usually would, or you could have trouble remembering things. Is it your imagination? Maybe not.

Experts used to think of migraines primarily as headaches that could be severe enough to be put people out of action for days. Now though, experts tend to see migraine as more of a chronic disorder, punctuated with periodic episodes of headaches. They believe that people with migraines may have particularly sensitive brains that can be triggered by a variety of factors, from chocolate to changes in the weather.

If you experience “brain fog” - cognitive impairment - during a migraine, you may feel confused, have difficulty learning or remembering, or have trouble speaking or reading. These symptoms are considered part of the disorder. The good news is that the impairment is temporary and does not result in cumulative mental decline over time. In fact, one long term, extensive study showed that many people with migraines are actually better thinkers than people who don’t have them. 

When a migraine episode does occur, it may come in as many as four phases. Your “brain fog” may be worse during some parts of an attack than others. Here’s a look at how your mind and abilities may change before, during and after a migraine headache.

Phase 1: Before the Headache

Up to two days before a migraine headache kicks in, you may have symptoms during what is called the prodrome phase. You might find yourself experiencing emotional changes or having trouble concentrating. An estimated 40% of people who have migraines, who are called migraineurs, may experience these kinds of changes leading up to a headache.

Phase 2: The Aura

The visual or other sensory disturbances that about a quarter of people with migraines experience are a sign of an attack about to happen. This phase usually lasts under an hour and includes seeing flashing lights or dots, having blind spots, or being hypersensitive to smells and sounds. During the aura, you may also feel confused, weak or dizzy, or have trouble speaking – in other words, “brain fog.” Most people will develop throbbing pain afterwards, though it’s possible to have the aura and not develop the headache.

Phase 3: During the Headache

The intense pain and light sensitivity that often accompany a migraine headache is bad enough, but you may also find you cannot read as quickly as you usually can or that your memory seems faulty. Cognitive tests have shown that those changes are real – during a migraine your ability to think clearly and remember things may diminish. There has been some debate about whether this part of migraine “brain fog” is the result of the pain itself, but many experts believe it is a separate symptom.

Phase 4: After the Headache

For a day or so after a migraine, which is called the postdrome phase, you may feel exhausted and irritable. People often describe it as feeling “wiped out” or “hung over.” Or, on the other hand, you may experience some euphoria  - an intense feeling of happiness.  It may be difficult to function well for a little while after a migraine, but the symptoms should disappear within a day or so and your brain fog should lift.

Migraines can be tough to deal with. The earlier you can recognize the onset of a migraine, the better. Early treatment may shorten the duration of the episode and get you back to being pain free and thinking clearly. If you are experiencing severe headaches, whether or not you have “brain fog” along with them, see your healthcare provider, who can help you assess whether or not you have migraines and talk to you about prevention and treatment.

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Medical Reviewer: William C. Lloyd III, MD, FACS
Last Review Date: 2022 Aug 21
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THIS TOOL DOES NOT PROVIDE MEDICAL ADVICE. It is intended for informational purposes only. It is not a substitute for professional medical advice, diagnosis or treatment. Never ignore professional medical advice in seeking treatment because of something you have read on the site. If you think you may have a medical emergency, immediately call your doctor or dial 911.
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