Complex jobs 'may protect brain'
Complex jobs that require a lot of difficult analysis or social interaction may protect the brain from mental decline, research suggests.
Social workers, lawyers, architects and graphic designers are likely to have longer-lasting memory and thinking skills than those in simpler occupations, say scientists.
The study involved testing the memory and thinking ability of 1,066 Scottish people with an average age of 70.
Researchers also collected information about the jobs participants held or used to hold before retiring.
Jobs were assigned scores for social or analytical complexity.
Work that involved co-ordinating or synthesising data was rated as complex, while copying or comparing data was at the simpler end of the scale.
For social occupations, complex roles included instructing, negotiating or mentoring, while more simple jobs involved taking instructions or helping.
Lead scientist Dr Alan Gow, from Heriot-Watt University in Edinburgh, said: "These results suggest that more stimulating work environments may help people retain their thinking skills, and that this might be observed years after they have retired.
"Our findings have helped to identify the kinds of job demands that preserve memory and thinking later on."
Complex "people" jobs included lawyer, social worker, surgeon, and probation officer.
Among those jobs with lower complexity scores for working with people were factory worker, bookbinder, painter and carpet layer.
In the data category, complex jobs included architect, civil engineer, graphic designer and musician. Simpler jobs included construction worker, telephone operator and waiter.
Participants in more complex jobs had better memory and thinking test scores, even taking into account IQ at age 11, years of education, and living environment.
Overall the effect of occupation was small, accounting for about 1% to 2% of the differences between people with complex or simple jobs.
This is comparable with, for instance, the association between non-smoking and better thinking skills later in life.
The research is published in the journal Neurology.
Dr Gow added: "Factoring in people's IQ at age 11 explained about 50% of the variance in thinking abilities in later life, but it did not account for all of the difference.
"While it is true that people who have higher cognitive abilities are more likely to get more complex jobs, there still seems to be a small advantage gained from these complex jobs for later thinking skills."