Migraines are generally considered a relatively benign neurological condition. However, research has shown an association between migraines and stroke, and especially between migraine with aura and ischaemic stroke. Patients can also suffer from migrainous infarction (blood clot), a subset of ischaemic stroke that often occurs in the posterior circulation of younger women. The exact origina of migrainous associated infarction is not known, but it is theorised that the duration and local neuronal energy level from cortical spreading depression may be a prime factor.