What is a stroke?

There are two types of stroke, bleeding and ischaemic. The first happens when a blood vessel begins to leak blood into the brain, this damages brain cells and results in loss of function. The second happens when a clot forms in one of the arteries in the brain. The loss of blood supply damages and may kill brain cells. Sometimes there is a strange effect which starts off with a clot, which the body tries to dissolve. If the body breaks down the clot after the cells in the blood vessel wall have died then blood may escape into the brain.

The effects depend on which cells were killed, which just damaged and whether the body can find another route through the brain to accomplish the same task. If most of a specialised area of the brain has been killed then very little recovery of that function can be expected. Common areas which cause this type of problem are areas specialised for speech and vision processing.

Recovery slows down with time, functional recovery (which may be learning to use remaining function more effectively as well as brain recovery) may go on for a year or two even if progress is slow.