If the title of this blog struck you as brash, I came by it honestly: it's the title of a terrific new paper by three NYU researchers (Protzko, Aronson & Blair, 2013). The authors sought to review all interventions meant to boost intelligence, and they cast a wide net, seeking any intervention for typically-developing children from birth to kindergarten age that used a standard IQ test as the outcome measure, and that was evaluated in a random control trial (RCT) experiment.

A feature of the paper I especially like is that none of the authors publish in the exact areas they review. Blair mostly studies self-regulation, and Aronson, gaps due to race, ethnicity or gender. (Protzko is a graduate student studying with Aronson.) So the paper is written by people with a lot of expertise, but who don't begin their review with a position they are trying to defend. They don't much care which way the data come out.

So what did they find? The paper is well worth reading in its entirety--they review a lot in just 15 pages--but there are four marquee findings.

First, the authors conclude that infant formula supplemented with long chain polyunsaturated fatty acids boosts intelligence by about 3.5 points, compared to formula without. They conclude that the same boost is observed if pregnant mothers receive the supplement. There are not sufficient data to conclude that other supplements--riboflavin, thiamine, niacin, zinc, and B-complex vitamins--have much impact, although the authors suggest (with extreme caution) that B-complex vitamins may prove helpful.

Second, interactive reading with a child raises IQ by about 6 points. The interactive aspect is key; interventions that simply encouraged reading or provided books had little impact. Effective interventions provided information about how to read to children: asking open-ended questions, answering questions children posed, following children's interests, and so on.

Third, the authors report that sending a child to preschool raises his or her IQ by a little more than 4 points. Preschools that include a specific language development component raise IQ scores by more than 7 points. There were not enough studies to differentiate what made some preschools more effective than others.

Fourth, the authors report on interventions that they describe as "intensive," meaning they involved more than preschool alone. The researchers sought to significantly alter the child's environment to make it more educationally enriching. All of these studies involved low-SES children (following the well-established finding that low-SES kids have lower IQs than their better-off counterparts due to differences in opportunity. I review that literature here.)  Such interventions led to a 4 point IQ gain, and a 7 point gain if the intervention included a center-based component. The authors note the interventions have too many features to enable them to pinpoint the cause, but they suggest that the data are consistent with the hypothesis that the cognitive complexity of the environment may be critical. They were able to confidently conclude (to their and my surprise) that earlier interventions helped no more than those starting later.

Those are the four interventions with the best track record. (Some others fared less well. Training working memory in young children "has yielded disappointing results." )

The data are mostly unsurprising, but I still find the article a valuable contribution. A reliable, easy-to-undertand review on an important topic.

Even better, this looks like the beginning of what the authors hope will be a longer-term effort they are calling the Database on Raising Intelligence--a compendium of RCTs based on interventions meant to boost IQ. That may not be everything we need to know about how to raise kids, but it's a darn important piece, and such a Database will be a welcome tool.

A lot of data from the last couple of decades shows a strong association between executive functions (the ability to inhibit impulses, to direct attention, and to use working memory) and positive outcomes in school and out of school (see review here).  Kids with stronger executive functions get better grades, are more likely to thrive in their careers, are less likely to get in trouble with the law, and so forth. Although the relationship is correlational and not known to be causal, understandably researchers have wanted to know whether there is a way to boost executive function in kids.

Tools of the Mind (Bedrova & Leong, 2007) looked promising. It's a full preschool curriculum consisting of some 60 activities, inspired by the work of psychologist Lev Vygotsky. Many of the activities call for the exercise of executive functions through play. For example, when engaged in dramatic pretend play, children must use working memory to keep in mind the roles of other characters and suppress impulses in order to maintain their own character identity. (See Diamond & Lee, 2011, for thoughts on how and why such activities might help students.)

A few studies of relatively modest scale (but not trivial--100-200 kids) indicated that Tools of the Mind has the intended effect (Barnett et al, 2008; Diamond et al, 2007). But now some much larger scale followup studies (800-2000 kids) have yielded discouraging results.

These studies were reported at a symposium this Spring at a meeting of the Society for Research on Educational Effectiveness. (You can download a pdf summary here.) Sarah Sparks covered this story for Ed Week when it happened in March, but it otherwise seemed to attract little notice.

Researchers at the symposium reported the results of three studies. Tools of the Mind did not have an impact in any of the three.

What should we make of these discouraging results?

It's too early to conclude that Tools of the Mind simply doesn't work as intended. It could be that there are as-yet unidentified differences among kids such that it's effective for some but not others. It may also be that the curriculum is more difficult to implement correctly than would first appear to be the case. Perhaps the teachers in the initial studies had more thorough training.

Whatever the explanation, the results are not cheering. It looked like we might have been on to a big-impact intervention that everyone could get behind. Now we are left with the dispiriting conclusion "More study is needed."



Barnett, W., Jung, K., Yarosz, D., Thomas, J., Hornbeck, A., Stechuk, R., & Burns, S.(2008). Educational effects of the Tools of the Mind curriculum: A randomized trial. Early Childhood Research Quarterly, 23, 299–313.

Bedrova, E. & Leong, D. (2007) Tools of the Mind: The Bygotskian appraoch to early childhood education. Second edition. New York: Merrill.

Diamond, A. & Lee, K. (2011). Interventions shown to aid executive function development in children 4-12 years old. Science, 333,  959-964.

Diamond, A., Barnett, W. S., Thomas, J., & Munro, S. (2007). Preschool program improves cognitive control. Science, 318, 1387-1388.