The negative link between religiosity and intelligence remains stable over time in older adults

(Photo credit: Adobe Stock)

In a study spanning over a decade, researchers found no evidence to suggest that religious practices, such as praying or attending religious services, have a protective effect against cognitive decline in older adults. Contrary to some expectations, the study indicated a consistent, albeit small, negative association between cognitive abilities and religiosity, remaining stable over time. The findings have been published in the journal Intelligence.

Prior studies have generally shown a negative correlation between cognitive abilities and religious beliefs and behaviors. However, there was a growing hypothesis that religiosity might act as a protective factor against cognitive decline, especially in the elderly. This notion stemmed from observations that religious involvement could offer social engagement and mental stimulation, potentially buffering against the cognitive impairments commonly associated with aging. Understanding this relationship is particularly crucial given the rising global prevalence of dementia and other age-related cognitive disorders.

“Like many people I’m interested in the big questions: Why are we here? Where do we come from? Is there life after death? Is there a deeper meaning to life? Is there a God? – but I’m also fascinated by the fact that people find so different answers to these questions and if this might be associated with certain human traits,” said study author Florian Dürlinger, a clinical psychologist and external lecturer at the University of Vienna.

“So, I became interested in reasons why people turn to religion in general and in religiosity and intelligence associations in particular. Religiosity (although there have been negative impacts on humanity and human lives undoubtedly) seems to have a lot of (secular) merit too – otherwise it wouldn’t exist. The well-established small negative correlation of religiosity and intelligence could be seen as an indicator thereof.”

“Religion has the potential to fulfill psychological needs and desires and so does intelligence,” Dürlinger explained. “However, we might not do justice to the understanding of this relation if we only examine it cross-sectionally. The effects of religiosity on cognitive declines have previously been investigated, but mostly in more religious regions than (Western) Europe: predominantly in America, but also in Asia – and with diverging results. Some authors proposed a slower decline in religious people while others suggested an even faster decline. We therefore conducted a large-scale assessment including mostly Western European countries.”

The study involved a detailed analysis of data from the Survey of Health, Aging, and Retirement in Europe (SHARE), covering individuals aged 50 and above from 28 European countries and Israel. The researchers examined data from three waves of this survey, spanning 2004, 2007, and 2013, including over 30,000 participants in the initial wave.

The participants’ cognitive abilities were measured through a series of tasks. These tasks assessed numeracy (basic mathematical skills), verbal fluency (the ability to name as many animals as possible in one minute), and memory (recalling a list of words immediately and after a delay). To gauge religiosity, the participants were asked about their frequency of praying and participation in religious services.

There was a small but consistent negative association between cognitive abilities and religiosity. Individuals who engaged more frequently in religious activities, such as praying, tended to have lower scores in cognitive tasks assessing numeracy, verbal fluency, and memory. This cross-sectional correlation persisted even after controlling for other factors like age and sex.

In their longitudinal analysis of the data, which tracked changes in cognitive abilities over time, the researchers found that the negative association between cognitive abilities and religiosity remained stable. This suggests that religiosity does not affect the cognitive decline of individuals.

“Our main finding is that religiosity does not protect against cognitive declines,” Dürlinger told PsyPost. “We instead found that the small negative correlation of religiosity and intelligence does not show meaningful within-individual changes over time (as it should if religiosity had any impact on cognitive functions in later life).”

But the study, like all research, includes some limitations. The age range of the participants might have influenced the findings. “It needs to be stated that due to the nature of our sample (participants from the SHARE database are 50 years or older) attrition was major and we were only able to include three times of data collection, covering a time span of nine years,” Dürlinger said. “So, we cannot entirely rule out that protective effects – if there are any – may manifest themselves only after 62 years, which represents the mean age of our participants in the last Wave of data collection.”

The study also considered the impact of societal religiosity, that is, the overall level of religious engagement in different countries. It was observed that in countries with higher overall levels of religiosity, the decline in cognitive abilities was somewhat faster. However, this trend was not uniformly observed across all countries, especially when countries with extremely high religiosity levels (like Greece) were removed from the analysis. This suggests that the impact of societal religiosity might be more complex and nuanced.

“We could not provide robust evidence for a moderation by societal religiosity,” Dürlinger said. “This, however, could be due to the low variance of national religiosity estimates for the countries included. Future research could address the question of potential moderating effects of societal religiosity possibly explaining why effects were found in the United States but not in Western Europe.”

“Although we cannot answer this conclusively with our data, to me personally it seems that if religiosity has the potential to protect against cognitive declines, it is probably due to its behavioral aspects, like socializing, praying, reading, etc,” Dürlinger added. “Those effects, which might come out as more beneficial in more religious societies, could be obtained without religion or a belief in God as well: That an active lifestyle is conductive to a healthy cognitive ageing is something we have already known.”

The study, “Religiosity does not prevent cognitive declines: Cross-sectional and longitudinal evidence from the Survey of Health, Aging and Retirement in Europe“, was authored by Florian Dürlinger, Jonathan Fries, Takuya Yanagida, and Jakob Pietschnig.

© PsyPost