“Brain training” does not improve general cognitive function, according to a 6-week trial of more than 11,000 participants.
The study results “provide no evidence for any generalized improvements in cognitive function following brain training in a large sample of healthy adults,” Adrian M. Owen and his colleagues reported.
The participants were divided into three groups: the experimental group 1 (4,678 subjects), which did six tasks emphasizing reasoning, planning, and problem solving; experimental group 2 (4,014 subjects), which practiced six tasks focusing on short-term memory, attention, visuospatial processing, and mathematics; and a control group (2,738 subjects), which answered various research questions using the Internet, said Mr. Owen of the Medical Research Council Cognition and Brain Sciences Unit, Cambridge, England, and his colleagues.
The participants were assessed before and after the intervention using benchmarking tests that measuring reasoning, verbal short-term memory, spatial working memory, and paired-associates learning.
All three groups improved on the tasks they had been assigned topractic the trial (effectstintervention improvementson the beh smaller (effect sizes: 0.01-0.22 for all groups).
No relationship was seen between number of training sessions performed or age of participants and postintervention benchmarking test scores. The scores on two tests reflected small gender differences.
Although participants improved at their assigned tasks, “training-related improvements may not even generalize to other tasks that use similar cognitive functions,” the researchers said (Nature 2010 Apr. 20 [doi: 10.1038/nature09042
The authors reported no financial conflicts of interest.
My Take
Credible Study on Complex Question
The notion of exercising the mind to reduce its deterioration is popular in the world of Alzheimer's disease.
Do more crossword puzzles and you will slow the progression of dementia. But is it true? Epidemiological studies have shown mixed results, possibly reflecting presymptomatic-stage disease, confounding medical issues, and medications influencing outcomes. Functional brain imaging studies show activation of prefrontal cortices during the early attentional practice stage that diminishes and ultimately vanishes as any skill becomes automatic (Proc. Natl. Acad. Sci. USA 1998;95:853-60).
Cognitive tasks, in contrast to sensorimotor tasks, rely on the integration of multiple brain regions that are geographically distant and serve different functions. Because a related, nonidentical task might use this network, it is conceivable that related tasks may be performed with greater facility and dexterity.
Given the effort required to achieve even a “simple” practice effect, studies such as that of Adrian M. Owen and his colleagues that fail to show any major translational skill differences after a mere 6 weeks of “brain exercises” that sound far less grueling than the practice of professional musicians and athletes are certainly credible.
RICHARD J. CASELLI, M.D., is a professor of neurology at the Mayo Clinic Arizona, Scottsdale. He has no financial conflicts of interest related to this subject.
