Lay-offs and enforced part time work and lower paid, lower status jobs (downward job mobility), sparked by recessions, may explain the toll taken on cognitive ability - memory, verbal fluency, temporal orientation, and numeracy - the findings suggest.
Previous research suggests that working conditions may influence the potential to build up "cognitive reserve," which in turn influences cognitive performance at a later age.
But higher cognitive ability to start with may select individuals into more favourable jobs and working environments, so the authors wanted to find out if economic recessions, over which individuals have no control, made any difference.
They therefore analysed data from 12,000 people in 11 countries, who took part in the representative Survey of Health, Ageing, and Retirement in Europe (SHARE). This looks at the health, employment, and social conditions of Europeans aged 50 and older.
Participants' cognitive abilities were assessed in 2004-5 and 2006-7. The results were linked to detailed work histories, retrospectively collected in 2008-9, as well as annual data on per capita fluctuations in Gross Domestic Product (GDP) in each country between 1959 and 2003, to gauge the number and depth of economic downturns.
The researchers then looked at the potential impact of recessions experienced at ages 25-34, 35-44, and 44-49 on cognitive ability at ages 50-74.
And they took account of a wide range of potentially influential factors, including: birth before or after World War II; self-rated health; material deprivation; occupation of main breadwinner in the household; number of books in the home; self-reported skills in their mother tongue and maths; educational attainment; and type of first job.
The average number of recessions experienced ranged from 0.73 for men between the ages of 45 and 49 to 1.33 for women between the ages of 35 and 44.
The analysis showed that men who did not live through any recession in their mid to late 40s had a mean cognitive score of minus 0.07 at ages 50 to 74, compared with a mean score of minus 0.12 for those experiencing four or more recessions. The impact of a recession on women seemed to occur earlier - in their mid 20s to mid 30s, with the equivalent figures minus 0.05 and 0.17, respectively.
Economic recessions during these periods were associated with several labour market outcomes, such as lay-offs, enforced part-time working, and the need to take lower paid, lower status work.
Journal of Epidemiology & Community Health