Posts Tagged ‘Meta-analysis’

The Benefits of Physical Exercise & Cognitive Training on the Executive Function of Older Adults

February 22, 2015

As the name implies, executive function is important.  It involves the prefrontal cortex, which has a high level of neural plasticity (Miller, E.K., & Cohen, D.J. (2001),  “An Integrative Theory of Prefrontal Cortex Function,” Annual Review of Neuroscience, 24, 167-201. doi:10.1146/annurev.neuro.24.1.167), meaning that it is amenable to training.  This current blog post provides a very brief summary of an article by Justin E. Karr, Corson N. Areshenkoff, Phillipe Rast, and Mauricio A. Garcia-Barrera titled “An Empirical Comparison of the Therapeutic Benefits of Physical Exercise and Cognitive Training on the Executive Functions of Older Adults:  A Meta-Analysis of Controlled Trials” in Neuropsychology (2014), 829.845.

A meta-analysis is an analysis of a large body of research.  This one involved 46 studies, 23 involving physical exercise (PE), 21 cognitive training (CT), and 2 involving both.  Cognitive training did not work for individuals who were already cognitively impaired.  Otherwise, both types of training improved executive functions, but CT presented potential advantages for specific types of cognitive functions.  The immediately previous post discussed these executive functions:  working memory, inhibition, executive attention, problem solving, and fluency.  The review found that cognitive training on problem solving had the largest beneficial effect on the measure of Independent Activities of Daily Living (IADL).

Although the study found that the effects of cognitive training were larger than physical exercise, they qualified this conclusion.  I would contend that it is foolish to argue which is better.  They both provide benefit.  Presumably the major benefit from physical exercise is due to aerobic activity increasing oxygen flow to the brain.  I am curious as to whether any activity that increases respiration might be beneficial,  laughing for example.  Feel free to add whatever techniques you can think of for increasing respiration.  I think it would be worthwhile for researchers to explore possible benefits of these types of activities.  One of the primary advantages of cognitive training is that they can be targeted at specific cognitive functions.  Further research could be explored at designing training to improve specific functions where training is most needed.  The types of training might vary among individuals.  This meta-view has found that, general speaking, problem solving skills had the largest effect.

© Douglas Griffith and healthymemory.wordpress.com, 2015. Unauthorized use and/or duplication of this material without express and written permission from this blog’s author and/or owner is strictly prohibited. Excerpts and links may be used, provided that full and clear credit is given to Douglas Griffith and healthymemory.wordpress.com with appropriate and specific direction to the original content.

Making Working Memory Work for Older Adults

October 25, 2014

This blog post is taken from the article in Psychological Science (8 October 2014 DOI: 10.1177/095679761458725) by Julia Karbach and Paul Verhaeghen titled “Making Working Memory Work: A Meta-Analysis of Executive-Control and Working Memory Training in Older Adults.” It examined the effects of process-based executive-function and working memory training in older adults (>60 years). This analysis included 49 articles and 61 independent samples. This is an extremely important article for a couple of reasons. Weaknesses in the cognitive performance of older adults have been localized to fluid intelligence, the activities that involve executive control and working memory. As we know from the healthymemory blog post “The Myth of Cognitive Decline” the crystalized intelligence of older adults holds steady and even grows. The sometimes apparent slowness in recall and the difficulty in recalling certain items is due to the enormous amount of information that has accumulated in memory. Most, if not all, of those memories are available if not accessible and will pop into memory at some later time.

The second reason that this article is so important is that it is a meta-analysis of the relevant literature. A meta-analysis is a review and synthesis of the research. And it is the most impressive meta-analysis I have every read. It uses a sophisticated quantitative methodology, one that circumvents the problems noted in the healthymemory blog post, “Most Published Research Findings are False.” This meta-analysis can be regarded as a Gold Standard for meta-analyses.

So the conclusion is clear that these interventions do improve cognitive functions in the aging brain. Moreover, older people benefit just as much as younger people. Previously found age differentials do not maintain.

As an item for future research the authors argue that follow-up research should address the question as to whether the benefits of these interventions will hold over time. Frankly I find this question to be naive and unnecessary. The answer depends on whether these individuals continue to exercise their capabilities after the formal training ends. If someone takes golfing lessons and then does not play golf, would it be surprising if golfing skill declined? If someone learns to play a musical instrument and then no longer plays once the lessons have stopped, would it not be expected that performance on the instrument would decline. So the answer to the questions depends on whether the individual continues to be cognitively engaged and continues to engage in effortful learning (see the healthymemory blog post “The Adult Brain Makes New Neurons and Effortful Learning Keeps Them Alive.”

This is the constant theme of the healthymemory blog. Stay both cognitively and socially engaged and continue to learn till the very end.

© Douglas Griffith and healthymemory.wordpress.com, 2014. Unauthorized use and/or duplication of this material without express and written permission from this blog’s author and/or owner is strictly prohibited. Excerpts and links may be used, provided that full and clear credit is given to Douglas Griffith and healthymemory.wordpress.com with appropriate and specific direction to the original content.