What is a Migraine Headache?
Migraine headache is often described as intense throbbing or pulsating head pain that interferes with a person's ability to go about normal daily functioning (Rizzoli 2012; NINDS 2012). Migraine headache pain is often made worse by physical activity (Walling 2012).
Migraine sufferers frequently describe the pain as being limited to one side of the head (Digre 2011a). However, some people do experience migraines on both sides of the head (Digre 2011b). Migraine is commonly associated with nausea, as well as light and/or sound sensitivity (Cutrer 2012). Although migraine duration varies from patient to patient, a typical attack lasts for several hours, and sometimes persists for up to several (e.g. 2-3) days (Walling 2012).
Various physical and/or psychological changes sometimes precede the onset of a migraine headache by a few hours to a few days. This phase of a migraine is called prodrome. The experience of prodrome varies from person to person but can include such things as appetite changes, loss of balance, mood changes, tiredness, neck stiffness, and changes in alertness. The prevalence of a distinct prodrome phase is not entirely clear because studies have reported differing rates, but a significant portion of migraineurs indicate that they experience symptoms that predict the onset of migraine. Individuals who have experienced migraine preceded by prodrome in the past may be able to recognize an impending headache based upon their prodrome symptoms and plan accordingly for the next hours or few days by taking steps such as avoiding rigorous or stressful activity and ensuring that they have adequate stock of migraine relief medication (Rossi 2005).
Approximately 25% of migraineurs will experience a pre-migraine phenomena called aura, which is a neurologic abnormality causing mostly visual, but also other sensory and/or movement disturbances that manifests within a few hours of a migraine headache (Cutrer 2012; Digre 2011c). Most experts believe that migraine aura is caused by a phenomena in the brain called cortical spreading depression (CSD), a slowly progressing wave of excitability followed by long-lasting neuronal inhibition (Bogdanov 2011a).