The researchers then followed the participants, none of whom had dementia or Parkinson’s disease at the time, for four years.

During this period, 321 individuals or 27.6 per cent died.

Amazingly, they found that the risk of death was 36 per cent higher for those who only got six of the answers correct compared to those who managed to identify 11 out of 12.

This association was true even when age, disability, depression, brain dysfunction and leisure activity was taken into account.