Language learning protects against dementia.
Language learning improves cognitive function, especially cognitive flexibility, in the over 65s, according to a Dutch study by Jelle Brouer and colleagues at the University of Groningen.
The proportion of the population over 65 in most countries is increasing as life expectancy increases and birth rates decline. Unfortunately, this phase of life is often accompanied by chronic ill health, one of these challenges being cognitive decline and dementia.
Life experiences which can reduce the risk or delay the onset of dementia include having more education and/or a challenging and stimulating job. Basically, the more cognitive stimulation a person has throughout life, the lower the risk.
One of the ways this might work is by increasing ‘cognitive reserve’. This is like having more money in the bank so that when the bills start coming in it takes longer to go bankrupt. What is less clear, is whether cognitive stimulation later in life can still be effective.
Learning a language is cognitively taxing and people who speak more than one language have been reported to delay the onset of Alzheimer’s by several years. Jelle’s study sought to establish whether language learning in later life could still improve cognitive function and consequently enlarge cognitive reserves.
During the pandemic, 43 monolingual Dutch speakers aged 65-78 were recruited, from February 2021 to November 2022. Due to the ongoing restrictions, all parts of the study were conducted online, apart from some tests which were sent by post.
The monolingual criterion was set at using Dutch for at least 80% of the time—not so straight forward in a region were 26 40% of people also speak a local minority language.
Participants were randomly split into three groups, each receiving an intervention lasting three months. Group 1 received communication-focussed English language teaching for 1-1.5 hours every fortnight.
Group 2 were given guitars and had music lessons 1-1.5 hours every fortnight. Both Groups 1 and 2 also had 45 minutes of home study every day. Learning and playing music is well-documented as protecting against cognitive decline and the underpinning brain areas involved overlap with those supporting language learning. Jelle was interested to see how the two interventions compared.
Group 3 had a series of 30-minute lectures on wide ranging topics such as, sign language and animal assisted therapy. These lectures were followed by online group discussions on the topic but there was no further self-study. This was a relatively low-activity intervention making this the control group, providing a baseline for comparison.
Participants were tested before and after the interventions, then four months later to see how long-lasting any effects might be. Tests included English proficiency and a battery of cognitive tests including global cognition, cognitive flexibility, episodic and working memory and attention.
Participants in both the language and music intervention groups showed improvements in cognitive function, especially cognitive flexibility and episodic memory compared to those attending the lecture series. There was very little difference between the two interventions in terms of outcomes, but the language group made greater gains in cognitive flexibility.
Given the small final sample size and multiple tests, it is not surprising that most of the comparisons were not significantly different. Recruitment required a long list of exclusions that, if present, could confound the results, such as: any history of cognitive, psychological or neurological problems; more than B2 level English; regularly playing music of any kind. Alongside the inevitable drop-out rate, this reduced the original enrolment from 199 to 43.
It was never very likely that differences between two positive interventions could be clarified with so few participants.
However, it is encouraging that language learning appears to be as effective as learning to play a musical instrument in improving cognitive sills in this age group and might even be better for improving cognitive flexibility.
The authors point out that if these interventions were extended, it would be important to maintain the level of cognitive challenge over time as individuals became more skilled at either language or music.
Another interesting finding was that participants with lower baseline cognitive scores at the beginning of the study tended to improve more after all interventions. Furthermore, improvements in language proficiency did not predict improvement in cognitive flexibility. This suggests that learners making less progress with the language learning itself still get the benefit to cognitive function.
The debate over the influence of age on language learning continues, but whether older people genuinely find language learning more challenging or not, the results of this study show that it is still very worthwhile to try.
REFERENCE
Brouwer, J., van den Berg, F., Knooihuizen, R., Loerts, H. and Keijzer, M. 2023. The effects of language learning on cognitive functioning and psychosocial well-being in cognitively healthy older adults: A semi-blind randomized controlled trial. Aging, Neuropsychology, and Cognition, 38: 195-213.
