<s>[INST] What is stroke? [/INST] A stroke, sometimes called brain attack, happens when blood supply to specific areas or parts of the brain is interrupted due to blocked or ruptured blood vessels. This prevents vital nutrients and oxygen reaching the brain causing severe damage to brain cells. This results in loss of function in the areas directly affected by the stroke due to tissue death; as well as the surrounding areas due to swelling and inflammation. Source: WEST SUFFOLK HOSPITAL. Link: https://www.wsh.nhs.uk/Services-A-Z/Stroke-early-supported-discharge/Frequently-asked-questions.aspx. Field: Neurology. Disease: Stroke </s>