Atheism not linked to cognitive decline (but it is linked to intelligence)

In Scotland, they’ve been following a group of people ever since they were born in 1921 (the Lothian Birth Cohort). Cohorts like this are great to see what factors early in life affect how people turn out as adults – so long as you ask the right questions early on!

One of the test they ran on the Lothian Cohort, when they were just 11, was an intelligence test. They didn’t test intelligence again until 2000, when the cohort was 79 (they tested them a few times since, as well). For the purposes of this study, they excluded those who developed dementia – so we are looking at just regular brain ageing here.

They only measured how religious they were at age 79, however. But that still provides an excellent opportunity to measure how childhood intelligence is linked to later life religiosity.

Well, the answer is that there was no correlation between intelligence at age 11 and later religious involvement, well-being (e.g. “I have a meaningful relationship with God”). And there was no correlation between changes in intelligence and any religious factor.

Now that’s something of a surprise, given that research in the US has suggested that religiosity is associated with lower cognitive ability but that religious attendance protects against cognitive decline (for example, research covered on this blog back in 2009).

What they did find, similar to other studies, was that there was a negative link between current  intelligence and religious belief. But the effect was even smaller than usually seen in these sorts of studies. And higher education was linked to more religious attendance – again, as seen in other studies.

Perhaps that’s because the people in this study were quite old, and so were perhaps more homogenous in their religion. Or it may be that, for people born in the early part of the 20th century, the link between religion and intelligence is weaker.

Or maybe it’s the generally lower levels of religion in the UK that explains the differences to previous research.

The truth is that religion in the UK is a complicated fish. As other research has shown, there doesn’t seem to be a linear relationship between education (or intelligence) and religion.

Rather, what happens is that intelligent and well educated people tend to have a strong stance – either decidedly religious, or (more often) decidedly atheist.

People with less education are not exactly agnostic. They just don’t seem to care!

Ritchie, S., Gow, A., & Deary, I. (2014). Religiosity is negatively associated with later-life intelligence, but not with age-related cognitive decline Intelligence, 46, 9-17 DOI: 10.1016/j.intell.2014.04.005

This article by Tom Rees was first published on Epiphenom. It is licensed under Creative Commons.