Provocative evidence that certain memory exercises make people smarter has sparked the rise of online brain-training programs such as Lumosity. But at least one type of brain training may not work as advertised, a new study finds.
As expected, practicing improved volunteers’ performance on tests of memory and the ability to locate items quickly in busy scenes, say psychologist Thomas Redick of Indiana University Purdue University Columbus and his colleagues. That improvement did not, however, translate into higher scores on tests of intelligence and multitasking, the researchers report in the May Journal of Experimental Psychology: General.
Redick’s investigation is part of a growing scientific debate about brain training, which is promoted by some companies as having a variety of mental benefits. Some researchers say that extensive instruction and training on memory tasks can indeed fortify reasoning and problem solving. Others are skeptical that vigorous memory sessions produce such wide-ranging effects. The dispute feeds into a long-standing scientific controversy about whether enriched environments can increase intelligence, as measured on IQ tests.
What’s not up for debate is that many people feel smarter after brain training. In the new study, 10 of 23 individuals who completed memory sessions said that the program helped them to think, multitask and focus better in daily life.
But the scientists say that even if some participants performed daily tasks better after memory training, they may simply have tried harder or felt better about their efforts due to a belief that training had strengthened their minds.
Redick’s team studied 73 young adults, ages 18 to 30, split into three groups. One group completed 20 training sessions over about six weeks on a task aimed at boosting working memory, the ability to keep in mind and compare several pieces of information. Versions of this working memory task are featured in many commercial brain-training programs.
In this task, volunteers watch blocks pop up at various spots on a computer screen. With each block presentation, volunteers hear a spoken consonant. Participants are instructed to press a computer key if a block’s location and the accompanying consonant matched the pair encountered immediately before. Depending on an individual’s performance, the task becomes harder, requiring matching of pairs shown two to four instances earlier, or easier. Psychologist Susanne Jaeggi of the University of Maryland in College Park reported in 2008 that this form of working memory training upped volunteers’ reasoning and problem-solving skills (SN: 5/24/08, p. 7).
A second group in the new study received 20 training sessions aimed at improving the ability to pick out novel shapes from large arrays of similar-looking shapes. This group provided a comparison to see whether the effects of memory training differed from training on a different mental skill. A third group received no training.
In the two training groups, volunteers improved with practice on the task they were learning but showed no increases on tests of intelligence and of the total amount of information that could be held in mind.
Participants in the new study didn’t receive enough instruction and practice before memory sessions to benefit from the intervention, Jaeggi says. Redick’s group also gave volunteers limited time to complete a series of shortened versions of standard intelligence tests, which probably limited any potential for scoring increases, she asserts.
But until larger studies with longer follow-ups are completed, Redick cautions against assuming that memory training smartens people up.