Researchers said this could be a result of not exercising enough, drinking too much alcohol, loneliness and depression - issues which were all exacerbated by the pandemic.
Researchers from the University of Exeter and the Institute of Psychiatry, Psychology & Neuroscience (IoPPN) at King’s College London assessed the brain health of 3,142 people in the UK aged between 50 and 90 who all participated in the Protect Study.
Findings showed the cognitive decline was especially rapid in the first year of the pandemic. It was also higher among those who had already shown signs of mild cognitive decline before the pandemic.
Head of policy at Alzheimer’s Research UK, Dr Susan Mitchell, said the study demonstrates "how the profound lifestyle shifts triggered by the lockdown restrictions might have influenced the nation’s brain health.
“In doing so, it underlines the fact that there are steps we can all take to protect the health of our brain.
“Our own analysis has shown that just 2% of people say they’re doing all they can to optimise their brain health..."
How is brain health measured?
Experts have yet to identify a strong way to measure brain health, but MindCrowd, a research study designed to analyse how brain performance changes with age, has pointed out that reaction time may be one way.
This is because reaction time depends on central nervous system processing speed. Essentially, the healthier the brain, the faster its processing speed, memory and thinking skills.
The study's senior author Matt Huentelman, Professor of Neurogenomics and MindCrowd founder said “Our findings have begun to pull back the curtain on the intricate network connecting processing speed and cognition to more accurately describe the comparisons of healthy, versus pathological, brain aging.”
How to improve brain health
Charity Director at Age UK, Caroline Abrahams, told the Standard: “The findings in this study certainly ring true for us at Age UK. In response to a survey we conducted, thousands of older people told us they were finding it harder to remember things and to process new information since the start of the pandemic. Really this is exactly what we would expect, because most older people were stuck at home for long periods of time, unable to engage much with others and often largely immobile.
"This experience therefore reaffirms the importance of staying physically and mentally active as we age to support our brain health, and it's sad for many of the current generation of older people that this became so difficult for them, for reasons beyond their control..."
However, there are some things you can do according to AgeUK, which may enable you to improve brain health. To achieve a healthy brain, it is good to:
Eat healthyAccording to Age UK, Mediterranean diets and brain health are almost correlational.
A Mediterranean diet is associated with better cognitive functioning in old age, and lower risk of dementia and Alzheimer’s disease.
A study conducted by Age UK found that people who did not follow the Mediterranean diet and who did not have dementia were more likely to have a higher loss of total brain volume over three years, from the age of 70 to 73, than those who closely followed the diet.
Aim to get enough high-quality sleep
It's probable you've heard people banging the same drum when it comes to this one, but it really is necessary to get seven to eight hours sleep a night! Going to bed and getting up around the same time every day helps you to have a better night's sleep and routine.
Ensure you also stay away from all digital screens before bedtime and avoid watching TV in bed. LED light emitted by digital screens may prevent the brain from releasing the sleep hormone melatonin.
Increase physical activity
Age UK is clear on this one. People who lead a physically active lifestyle throughout their lives, typically have a lower-than-average risk of decline in thinking skills when it comes to ageing.
The same goes for ‘purposeful exercise’ – this is exercise involving moderate to vigorous exertion and it is done deliberately. In randomised controlled trials, people who took part in purposeful exercise showed beneficial changes in brain structure and function.
Become bilingual or multilingual
People who are bilingual develop dementia 4-5 years later than people who speak one language only,. They are also known to be twice as likely to recover their cognitive abilities after a stroke.
Bilingualism and multilingualism have been linked to better performance on different tests of thinking skills, including those used for screening for dementia.
Even short periods of intensive language learning can produce measurable positive effects on cognitive abilities. 5 hours per week is the recommended time to carve out in a week for learning one.