About 18 months ago, at the launch event for Wave 6 of the English Longitudinal Study of Ageing (ELSA), I had a brainwave. It was during a discussion of data from the Sexual Relationships and Activities questionnaire which was new for Wave 6, when the cogs started turning. I thought, if we know that all of these other health and lifestyle factors affect cognitive function – healthy diet, exercise, social contact – then why aren’t we looking at sexual relationships? It is surprising that something so ordinary had eluded research interest, especially in the field of older age.
Of course, the area hasn’t been totally neglected. Some researchers have explored how cognitive impairment impacts upon sexual relationships, in couples where one partner has dementia. This research highlights how cognitive impairment has knock-on effects on intimacy, and also raises ethical issues of consent between older couples (http://blog.oup.com/2015/09/sexual-decision-making-for-older-adults-with-dementia/). Whilst this is fascinating, I wondered whether sexual activity could affect cognitive function in healthy individuals – a kind of ‘role reversal’ for the key variables.
We used cross-sectional data from ELSA, taking account of factors that might influence either sexual activity or cognition – age, education, wealth, levels of physical activity, cohabiting status, general health, depression, loneliness and quality of life. Even after adjusting for all of these variables statistically, we established that there is indeed an association between sexual activity and higher scores on tests of cognitive function in people over the age of 50.
The release of this research paper has attracted a lot of international media interest. Some outlets have stuck to the facts and reported the science behind the findings, but there have also been the inevitable ‘regular sex stops dementia’ type headlines. There are a few glaringly obvious issues with these kinds of interpretations, from a scientific point of view.
It’s all too easy to jump to conclusions when dementia seems to be receiving so much public and political attention (https://www.gov.uk/government/publications/prime-ministers-challenge-on-dementia-2020), but our work focussed on cognitive function in healthy, unimpaired older adults. For us to make claims about cognitive decline, and indeed dementia, we now need to carry out prospective research to establish a causal relationship between sexual activity and cognition over time.
What is most surprising from the media interest, though, is the speed at which people sit up and listens when you mention sex. Which brings me back to my initial question – why we haven’t been researching the sex-cognition link before now?
Despite our neat findings and jazzy headlines, the story is not as straightforward as it first seems. For example, there were gender differences in our findings on a number sequencing task (e.g. fill in the blank “9, 7, _, 3”). That is, we did not find a significant association between sexual activity and performance on this task in women. We don’t have a definitive answer for this finding from the initial study we carried out – but we are really excited to explore the possible effect of hormonal influences on certain brain regions in men and women.
Closely linked to this idea, is another question of whether we are dealing with a biological or a social phenomenon. Our initial findings could be the result of heightened levels of intimacy and companionship that may be inherent in sexual relationships (that is, an increase in social contact). Or, there could be a purely biological explanation, where regular surges in arousal and release of sex-related hormones could be affecting brain function.
Of course, our answer could lie in a combination of the social and biological impact of sexual activity. It would be very interesting to hear your opinions on what you think is going on here. Nature or nurture, biological or social, love or sex?
There has been a long history of scientific and medical research into health- and lifestyle-related factors that promote or protect cognitive functions – especially memory – in older age. Nobody wants to lose the precious memories that they’ve spent their whole life collecting. Would it be so bad if we can add ‘healthy sex life’ to the growing list of (otherwise arduous) activities that might protect cognitive functions in later life?