Our brain power can change with the seasons, peaking in the late summer and autumn. [Photo: Bigstock]

Autumn brings a brainpower boost

13 September, 2018

Natural Health News — New research suggests that our brain power can change with the seasons.

A study conducted by researchers from the US, Canada, France and Israel, has discovered that adults over the age of 60 are significantly cleverer at the start of autumn compared with spring. The difference between the autumn and spring equinox say the scientists, was equivalent to four years of ageing.

The study analysed data involving more than 3,000 people in North America and Europe, most of whom were over 70. They had each been given annual tests of memory and processing speed, with their testing spread randomly throughout the year.

Doctors had assumed that the month the testing occurred was irrelevant, but the paper in the online journal Plos Medicine found that the seasons did matter. In fact, cognitive performance was shown to be higher in the summer and autumn compared with winter and spring. It peaked at the autumn equinox then dropped off until the spring equinox six months later.

Important considerations for dementia testing

For some participants, the researchers also looked at levels of proteins associated with Alzheimer’s disease. This revealed seasonal rhythms in Alzheimer-disease-related proteins in the spinal fluid, and in the expression of specific genes in the brain, giving us a window into the underlying mechanisms.

They found a 30% greater chance of meeting diagnostic criteria for mild cognitive impairment or dementia if cognitive tests are carried out in late-winter or early-spring. “The difference in performance was enough to impact the clinical impression of what diagnostic category a patient was going to be in,” said one of the researchers Andrew Lim, from the University of Toronto.

The team could only speculate on the cause of such a change. Light, temperature, the body’s hormone levels or vitamin D consumption could be to blame, Lim said. But on the bright side, the study opens up the possibility that “good cognition” could be extended beyond that peak time to prevent or slow the onset of Alzheimer’s disease.

One theory is that our lifestyle and health habits vary with the season, we may for instance eat, sleep and exercise differently.

Lead researcher Philip De Jager, from Columbia University, said another theory was that during winter our brains experienced something akin to a mild hibernation. “The underlying rhythms are similar to those that regulate many other mammals and animals,” he said. “They probably help us minimise activity in months when fewer resources are available and take advantage of them at a time when they are abundant.”