Aging. Can We Enhance People's Cognitive Outcomes?

If you work in the workplace learning-and-performance field, one of your jobs is to ensure that employees are maximizing their cognitive performance, their decision making, and their overall work output. If people's cognitive abilities decreased with age, that would be a problem. More importantly, if we can improve our employee's cognitive abilities, we have a responsibility to do just that. The benefits will accrue to our organizations and to our employees too (and probably then to their families and society at large).

This begs the following questions then:

• "Is there research in refereed scientific journals that provides evidence for cognitive decline as people age?"
• "Is there research in refereed scientific journals that provides evidence that we can help improve people's cognitive abilities as they age?"

I've created a short 4-item quiz for you to test your knowledge in this area. Take the quiz. When you are done it will return you directly to this blog post (is that cool or what)?

Take the Quiz. Test your Knowledge of Aging's Effect on Cognitive Ability.

Click here to take the quiz

The quiz is based on an article by Christopher Hertzog, Arthur F. Kramer, Robert S. Wilson, and Ulman Lindenberger.

HEY, what are you doing? Go take the quiz first. There's research to show that the sort of questions I ask in the quiz will actually help you remember this topic. Doh!

The article by Hertzog, Kramer, Wilson, and Lindenberger is in Volume 9—Number 1 in the refereed scientific journal Psychological Science in the Public Interest that was just published in 2009. The title of the article is: Enrichment Effects on Adult Cognitive Development Can the Functional Capacity of Older Adults Be Preserved and Enhanced?

HEY, really. Go take the quiz first!!

Both of my parents (75+) are doing everything right according to the article.


Findings:

Cognitive ability does tend to decline with age. See graph from the article:



But notice that though AVERAGE cognitive ability declines there are wide ranges. And since I'm 51 years old as I write this, I'd like you to note that maximum cognitive performance seems highest near 50 years of age.

Can Cognitive Ability be Improved?

Yes, these researchers conclude that it can. Although they admit that more research is needed.

What Can Improve Cognitive Ability?

Well, they didn't look at everything that might impact cognitive ability, so we don't have a clear picture yet.

They highlighted the strongest findings in their conclusion:

"The literature is far from definitive, which is no surprise given the inherent difficulties in empirically testing the enrichment hypothesis. However, we believe there is a strong and sound empirical basis for arguing that a variety of factors, including engaging in intellectually and mentally stimulating activities, both (a) slow rates of cognitive aging and (b) enhance levels of cognitive functioning in later life." p. 41

"What is most impressive to us is the evidence demonstrating benefits of aerobic physical exercise on cognitive functioning in older adults. Such a conclusion would have been controversial in the not-too-distant past, but the evidence that has accumulated since 2000 from both human and animal studies argues overwhelmingly that aerobic exercise enhances cognitive function in older adults. The hypothesis of exercise-induced cognitive-enrichment effects is supported by longitudinal studies of predictors of cognitive decline and incidence of dementia, but also by short-term intervention studies in human and animal populations. The exercise-intervention work suggest relatively general cognitive benefits of aerobic exercise but indicates that cognitive tasks that require executive functioning, working memory, and attentional control are most likely to benefit." p. 41

They also noted some other more-tentative findings:

"...these data support the idea that a higher level of social engagement is related to a reduced risk of cognitive decline and dementia in old age. The basis of the association is not well understood, however." p. 33

"...these data suggest that chronic psychological distress may contribute to late-life loss of cognition by causing neurodeteriorative changes in portions of the limbic system that help regulate affect and cognition, changes that do not leave a pathologic footprint (e.g., dendritic atrophy) or whose pathology is not recognizable with currently available methods. These changes, when extreme, might actually be sufficient to cause dementia, but it is more likely that they contribute to cognitive impairment and thereby increase the likelihood that other common age-related neuropathologies are clinically expressed as dementia" p. 36

"...in observational studies that examine more than one lifestyle factor, cognitive activities appear to be the strongest predictor of cognitive change. However, this could be the result of several factors, including the following: (a) Rarely are physical activities characterized in terms of intensity, frequency, and duration; (b) the period across which activities are assessed has been different for cognitive and physical activities; (c) with one exception, activities have been treated as unidimensional in nature. Clearly, these issues require additional consideration in future studies." p. 39

They also offer a word of caution about software programs that are marketed as ways to improve cognitive ability:

"The majority of software programs marketed as enhancing cognition or brain function lack supporting empirical evidence for training and transfer effects. Clearly, there is a need to introduce standards of good practice in this area. Software developers should be urged to report the reliability and validity of the trained tasks, the magnitude of training effects, the scope and maintenance of transfer to untrained tasks, and the population to which effects are likely to generalize. Arriving at thisinformation requires experiments with random assignment to treatment and control groups, and an adequate sample description. Just as the pharmaceutical industry is required to show benefit and provide evidence regarding potential side effects, companies marketing cognitive-enhancement products should be required to provide empirical evidence of product effectiveness." p.48

So, to answer the quiz questions:

1. What happens to most people's cognitive abilities as they age from 50 years onward? Answer: Declines with age.

2. Is there valid research evidence from scientific refereed journals that suggests that people can improve their cognitive outcomes by engaging in certain activities? Answer: Solid evidence, but still some controversy.

3. Which of the following have been shown to improve cognitive ability as people age. Answer: The article didn't cover all the territory, but the strongest evidence is for (1) mentally and intellectually challenging activities and (2) aerobic physical activity.

4. Imagine that you work for a company that consists of a substantial number of workers over the age of 50. If you had a set budget to spend to improve their cognitive functioning, which of the following investments would garner the greatest results? Answer: Well, the research review does NOT compare the differences between (1) mentally challenging activities, (2) aerobic exercise, and (3) social engagement. However, see their overall conclusion below, which suggests that intellectual engagement and physically activity are key.

Their overall conclusion:

"We conclude that, on balance, the available evidence favors the hypothesis that maintaining an intellectually engaged and physically active lifestyle promotes successful cognitive aging." p.1

More research on benefits of exercise:

"Unlike the literature on an active lifestyle, there is already an impressive array of work with humans and animal populations showing that exercise interventions have substantial benefits
for cognitive function, particularly for aspects of fluid intelligence and executive function. Recent neuroscience research on this topic indicates that exercise has substantial effects on brain morphology and function, representing a plausible brain substrate for the observed effects of aerobic exercise and other activities on cognition." p. 1

They cite the potential for training interventions:

"...cognitive-training studies have demonstrated that older adults can improve cognitive functioning when provided with intensive training in strategies that promote thinking and remembering. The early training literature suggested little transfer of function from specifically trained skills to new cognitive tasks; learning was highly specific to the cognitive processes targeted by training. Recently, however, a new generation of studies suggests that providing structured experience in situations demanding executive coordination of skills—such as complex video games, task-switching paradigms, and divided attention tasks—train strategic control over cognition that does show transfer to different task environments. These studies suggest that there is considerable reserve potential in older adults’ cognition that can be enhanced through training." p. 1

But they offer a warning against one-shot interventions:

"There is no magic pill or no one-shot vaccine that inoculates the individual against the possibility of cognitive decline in old age. As noted earlier, participation in intervention programs is unlikely to affect long-term outcomes unless the relevant behaviors are continued over time." p. 47

What do we have to do?

Well, if we take our job seriously, we ought to heed the research. We can improve our fellow employees cognitive abilities as they age, so we ought to figure out how we might support that.

I certainly haven't got this nailed but if your company is interested, I think it would be fascinating to see what we might do.