A migraine is a neurological condition characterized by severe headaches, often accompanied by symptoms like nausea, vomiting, and heightened sensitivity to light and sound. For some individuals, a distinct set of neurological symptoms, known as migraine aura, precedes or occurs concurrently with the headache. Aura represents temporary disruptions in brain activity.
Understanding Migraine Aura
Migraine aura involves a range of temporary neurological symptoms that develop gradually. The most frequently reported type is visual aura, where individuals might perceive flashing lights, bright spots, zigzag lines, or even experience blind spots. These visual disturbances are thought to arise from an electrical or chemical wave moving across the brain’s visual processing areas.
Aura can also manifest as sensory disturbances, typically involving tingling or numbness that may spread from one limb or side of the face. Speech difficulties, such as slurred speech or trouble finding words (aphasia), represent another type of aura, though less common. In rare instances, motor weakness on one side of the body can occur, characteristic of hemiplegic migraine.
Typical Aura Duration
Migraine aura symptoms typically have a predictable timeline. They usually begin gradually, developing over 5 to 20 minutes. For most people, these symptoms are transient and resolve within an hour, commonly lasting 20 to 60 minutes. This typical duration helps distinguish standard aura from other neurological events.
When Aura Lasts Longer
While most migraine auras are short-lived, some individuals experience symptoms that persist for hours or even days. This prolonged aura is less common but can occur. A specific medical term, “Persistent Aura Without Infarction” (PANI), describes a rare condition where aura symptoms continue for more than one week without evidence of brain tissue damage (infarction). This diagnosis requires that prolonged aura symptoms are similar to previous experiences and not attributable to another medical condition.
One underlying mechanism thought to contribute to aura is cortical spreading depression (CSD). This involves a slow-moving wave of electrical activity across the brain’s surface, followed by a period of reduced activity. In rare cases, such as hemiplegic migraine, motor weakness can extend for several days, though it typically resolves within 24 hours. Understanding why aura might persist for longer periods is an ongoing area of research, but it is distinct from typical, brief aura.
When to Seek Medical Attention
Seek medical evaluation if migraine aura symptoms are unusually prolonged, different from previous episodes, or accompanied by new neurological symptoms. Prolonged aura, especially if it involves motor weakness, can sometimes mimic serious conditions like a transient ischemic attack (TIA) or a stroke. Prompt medical assessment is crucial to rule out other causes and ensure an accurate diagnosis.
Contact a healthcare provider if an aura lasts longer than an hour, is a new experience, or includes significant muscle weakness or paralysis on one side of the body. While hemiplegic migraine is a recognized type of migraine with motor weakness, any new onset of such symptoms warrants immediate medical attention to determine the underlying cause. Healthcare professionals can help manage symptoms and differentiate between migraine aura and other neurological events.