Language Fluency Beats General Intelligence & Memory For Longevity

And no, it doesn’t have to be a second language, although that helps a lot:

An Underrated Tool Against Alzheimer’s ← you don’t even have to learn the second language to a high level, to benefit

Rather, what we’re talking about today is your first language fluency. So, for most of our readers, English. For the study participants it was German, because this was a German research team using data from the German population.

The Berlin Aging Study

Previous research has linked intelligence to longevity, but intelligence comprises multiple traits. So, what’s most important? Memory? General intelligence? Nope. Language fluency!

Let’s clarify something before we continue: “fluency” does not, in linguistics, mean what most people use it to mean. It’s not about the size of one’s overall knowledge of the language (e.g. vocabulary size), but rather, it is about one’s ability to speak and/or write fluently—literally, fluently means “flowingly”, i.e. without undue hesitation or difficulty.

The study used data from the Berlin Aging Study, which tracked 516 people aged 70–105 from 1989 onwards.

Researchers assessed four cognitive abilities, with two kinds of tests for each of:

• Verbal fluency (detailed description below)
• Perceptual speed (pattern-recognition speed)
• Verbal knowledge (vocabulary size)
• Episodic memory (personal memory recall)

General intelligence, meanwhile, was assessed as “the average of those 8 scores”.

The two tests for the cognitive ability of “verbal fluency” were:

Categories

Participants had to name as many different animals as possible within 90 seconds. Their answers were subsequently rated for correctness by two independent research assistants, to assure that noticed or unnoticed repetitions, wrong categories, and morphological variants were not coded as correct.

Word beginnings

Participants were asked to name as many different real words starting with the letter s as possible within 90 seconds. The named words were rated for correctness by two independent research assistants to avoid considering repetitions, morphological variants, and wrong words as correct.

You can read about these and the other tests for the other cognitive abilities, in the paper itself:

Verbal Fluency Selectively Predicts Survival in Old and Very Old Age ← if you’re looking for the test descriptions, scroll to “Method” and then scroll past the table, and you’ll see the test descriptions

They found that of all these metrics, only the two verbal fluency tests (and none of the other tests) showed a significant link to longevity.

Why this is important

Although the study does not prove causality (it could be that people who are predisposed to live longer for other reasons are more verbally fluent because of some common factor that influences both language fluency and longevity), it seems as good a reason as any to develop and maintain language fluency.

This builds on what was found in “The Nun Study“, that followed a convent of nuns (because they are a very homogenous sample in terms of occupation, location, diet, routine, etc, so a lot of confounding factors were already controlled-for) and made numerous major discoveries about things that impact aging (including the relevance of the APOE4 gene! That was The Nun Study).

When it came to nuns and language…

Based on the autobiographies written by the nuns in their youth upon taking their vows, there were two factors that were later correlated with not getting dementia:

• Longer sentences
• Positive outlook
• “Idea density”

That latter item means the relative linguistic density of ideas and complexity thereof, and the fluency and vivacity with which they were expressed (this was not a wishy-washy assessment; there was a hard-science analysis to determine numbers).

Want to spruce up yours? You might like to check out:

Reading, Better: Reading As A Cognitive Exercise

…for specific, evidence-based ways to tweak your reading to fight cognitive decline.

Take care!