The term 'dementia' is used to describe the symptoms that occur when the brain is affected by specific diseases and conditions.
Symptoms of dementia include loss of memory, confusion and problems with speech and understanding.
Dementia is progressive, which means the symptoms will gradually get worse.
For more information about dementia visit the Alzheimer's society website.
More top news
In a rallying call at the Democratic National Convention, the former US president said Hillary is 'the best darn change-maker I ever met'.
Satoshi Uematsu, 26, was sent to the Yokohama District Public Prosecutors Office in Kanagawa prefecture.
West Yorkshire Police confirmed a 32-year-old woman was taken into custody in connection with the alleged threats.