Cerebral infarction (a stroke) occurs when brain cells are deprived of oxygen. A stroke occurs because of a blockage in blood vessels leading to the brain. The blockage can be due to atherosclerotic plaque or an embolus forming beneath the inner lining a vessel lumen, which leads to the brain. This is known as an ischaemic stroke. A stroke can also occur if a damaged or weakened artery 'bursts' and bleed. This stroke is known as a haemorrhagic stroke. Ischaemic strokes are the most common form of stroke and numerous things increase the risk of them occurring. This includes: smoking, obesity, excessive alcohol intake. Brain cells deprived of oxygen can become damaged or even die.
The severity of the stroke and symptoms which occur depend on the the location of the brain which is deprived of oxygen.