Long-term negative emotions increase the risk of cognitive problems and may develop dementia later in life, a new study suggests. Pessimists in the study were found to have higher levels of protein in their brains, which are associated with the development of Alzheimer’s disease and dementia.
The study, from University College London, analysed the effects of negative thinking among adults over the age of 55. The results were somewhat unexpected — people with a practice called repetitive negative thinking (RNT) were more likely to experience cognitive decline as they got older.
In addition, people with long-term negative thinking patterns have also been found to have more harmful brain protein deposits, called tau and amyloid proteins. The build-up of these proteins was linked to dementia and Alzheimer’s disease, and was found in study participants through PET brain scans.
Past research has found that people with depression and anxiety are more likely to develop dementia later in life, and this new study may shed light on the reasons for the negative thinking patterns that are common in both cases.
The study involved nearly 300 participants over a two-year period, nearly half of whom also participated in PET brain scans. The researchers looked at several aspects of brain health, including memory, attention and language skills. Over a four-year period, participants in RNT were more likely to develop harmful protein deposition and memory problems, making them a risk factor for dementia.