Dementia is not a disease but the name given to a group of symptoms affecting memory, reasoning and decision-making. It is progressive – meaning symptoms are generally mild at first but worsen over time. “We describe dementia as an umbrella,” says Dr Brigid Ryan, a neuroscientist and research fellow with the Centre for Brain Research at the University of Auckland, “a group of symptoms that affect thinking and behaviour but can be caused by lots of different diseases – and the most common cause is Alzheimer’s.”
Alzheimer’s disease accounts for around 60-70 percent of all dementia cases. It is thought to be caused by an abnormal build-up of protein “plaques” and “tangles” within the brain and brain cells. These plaques and tangles disrupt regular brain cell activity, usually beginning in the
