And they also reduce perception and contribute to poor memory.

Are we naturally pessimistic? Do we see the glass as half empty? The news is not so happy from the scientific community.

A new study that saw the light of day recently found that constant negative thinking can lead, on the one hand, to a decrease in perception and on the other hand to an increase in two proteins responsible for Alzheimer’s disease.

“We believe that the tendency to think negative thoughts continuously is a new factor in the onset of dementia in humans,” said psychiatrist in the department of mental health at University College London and head of the research group, Dr. Natalie Marchand.

Negative thinking behaviors, such as doubting the past and worrying about the future, were measured in over 350 people over the age of 55 over a two-year period.

About a third of the participants also underwent a positron emission tomography (PET) brain scan to measure tau and beta amyloids, two proteins that cause Alzheimer’s disease, the most common type of dementia.

The results showed that people who had a higher number of negative thoughts had an increase in the two amyloids tau and beta, worse memory and a lower cognitive index compared to people who were not pessimistic.

The study also looked at levels of anxiety and depression and found a greater decline in perception in depressed and anxious people, which confirms previous research.

However, the levels of tau and beta amyloids did not show an increase in these subjects, leading the researchers to believe that persistent negative thinking is the main reason why depression and anxiety contribute to Alzheimer’s disease.

“Given other studies linking depression and anxiety to dementia risk, we believe that long-term negative thoughts could increase dementia risk,” said Dr. Natalie Marchand.

republished from the electronic edition of the newspaper Huffington Post