Klingberg took this idea and commercialized it. A number of companies are now providing such brain-enhancing aids. The goal is to improve short-term or "working" memory
There have, of course, been a number of subsequent studies that corroborated Klingberg’s original conclusion, and a number of studies that conflicted with his finding. Cook claims that this state of confusion has been resolved by some researchers who have performed a "meta-analysis" of all the data.
Cook would have us conclude that such games are a waste of time. But before we succumb to this reasoning let’s think about what we have just learned. And let’s also remind ourselves that studies of human responses are extremely difficult and easily biased. As was reported in Education: Testing and Conditional Intelligence it is rather straightforward to purposely, or inadvertently, affect performance in taking an intelligence test.
What we could be observing here is nothing more than researchers performing studies that generally produce the results they set out to obtain. The subsequent meta-analysis that was assumed to resolve all issues was merely an analysis of the previous analyses. Someone decided which studies were accurate and applicable and which were not; then a grand summation of the acceptable data was performed and a conclusion drawn. If one takes an average of a bunch of biased studies, does the bias disappear? Are those who perform meta-analyses automatically rendered free of bias? Can anything be known for sure?
Cook may be correct in concluding that the specific approach he discussed has been hyped beyond any defendable level. But his statement seems to deny the utility of all attempts to use mental exercises to improve brain function. That is going too far. He implies that those who resort to such mental exercises are mainly:
There is much more at stake than the desires of "ambitious parents." While Cook correctly pointed out the importance of "executive functions" and the tie between working memory and performance on intelligence tests, Paul Tough provides another perspective on these subjects in his book: How Children Succeed.
Tough tells of a study by Gary Evans and Michelle Schamberg of Cornell University. They tracked 195 children from birth to age seventeen. Half the children originated in families then having incomes below the poverty line, and half from middle class families. The goal was to assess their working memory as they aged. The tool they used was essentially the old Simon game where a child was presented with a sequence of colored lights and asked to reproduce the sequence.
Their studies concluded that performance on this working memory test was, in fact, correlated to the amount of time spent living in poverty.
This finding is consistent with the correlation between executive function and income, but does not provide a mechanism for this effect.
These researchers had also sought to monitor physiological attributes of the children. In particular, they were concerned with the effects of stress.
When they combined the physiological data with the poverty data and the working memory data, they concluded that the diminishment in working memory function was not due to poverty itself, but rather to the stress that could be induced by living in poverty. The subject of stress and physiological response was discussed in more detail in Poverty and Stress: The Ability of Children to Learn.
This research suggests that the ability of a child to utilize the brain he was born with is being compromised by physiological effects induced by his environment that effect brain function. These effects are best interpreted as interfering with the child’s ability to learn, rather than diminishing his intelligence.
There is hope that these effects can be alleviated, if not reversed.
There is too much at stake, and it is way too early to give up on the type of mental interventions that Gareth Cook so easily dismissed. Let’s let the researchers continue to contend with each other and hope that positive outcomes begin to emerge.