Why does your brain shrink?

http://www.sciencedaily.com/releases/2005/06/050611153907.htm

http://www.webmd.com/search/search_results/default.aspx?query=brain%20shrinkage&sourceType=undefined

Well, simply put… because if it grew, your head would explode.

Everything seems to shrink with age. I am 2 inches shorter than I was 20 years ago.

What symptoms caused him to get the brain scan?

Symptoms include :- had a dizzy episode about 8 weeks ago, admitted to hospital, had a 24 hrs heart monitor, results showed heart stopped for 4 mins ( 30 year history of heart condition and warfin medication) since this dizzy episode memory loss, short term and slightly confused. I am worried that this is not dimentia or altzimers as suggested but something more sinister.

There are lots of reasons why a brain would atrophy (or shrink). Given the history, the most likely explanation is repeated small strokes (I am assuming your dad is on warfarin for atrial fibrillation). People with atrial fibrillation often have strokes (thus the need for warfarin to prevent big atrial clots and big strokes). Other common explanations are the effects of high blood pressure and Alzheimers. Good luck.