Do brain games impact cognitive function?

Brain training applications, often called brain games, have become ubiquitous on smartphones and tablets. These apps promise to improve your cognitive abilities by playing just a few minutes a day, but a pair of letters from two groups of scientists have sparked a debate on such claims.

The first letter, written by a group of 70 international scientists and published in October 2014, claimed that brain games do not improve cognitive function or prevent cognitive decline. The letter states that while these games designed by professionals at top universities, the research is only related to the claims of the company. The group interviewed cognitive psychologists and neuroscientists from the Stanford Center on Longevity and the Berlin Max Planck Institute for Human Development.

“These findings do not provide a sound basis for the claims made by commercial companies selling brain games. Many scientists cringe at exuberant advertisements claiming improvements in the speed and efficiency of cognitive processing and dramatic gains in intelligence, in particular when these appear in otherwise trusted news sources. Exaggerated and misleading claims exploit the anxiety of adults facing old age for commercial purposes,” wrote the authors.

A few months later, another international group of 133 scientists wrote a response that stated that brain games can improve cognitive abilities. This letter claimed there is tangible evidence to suggest brain games help cognitive function. The authors express fear that readers will not believe the “dozens of randomized, controlled trials published in peer-reviewed journals that document specific benefits of defined types of cognitive training.”

“We believe that by not acknowledging (1) the training basis of the literature that shows that brain plasticity exists throughout the brain and throughout life, (2) the many demonstrations of the effectiveness of well-designed plasticity-based training regimens, and (3) the specific findings of efficacy in the area of aging, your statement derogates the time, effort and expertise of the thousands of scientists and clinicians engaged in designing, conducting, analyzing, publishing, and reviewing the research,” stated the second letter.

New developments

How can two groups of international teams of scientists reach two completely different results on the effectiveness of brain games?

The latest update in this debate is a study published by Psychological Science in the Public Interest, lead by Daniel Simons, a psychology professor at the University of Illinois at Urbana-Champaign. The researchers reviewed more than 130 studies on cognitive training therapies and brain games and examined top brain game apps such as Lumosity and LearningRx.

The study authors believe the differing results could stem from the different standards when trying to evaluate data.

“Methodological standards for intervention research have been relatively lax in much of the brain-training literature, and future research on this important topic should adhere more closely to best practices for intervention research, including preregistration, complete reporting, larger sample sizes and suitable controls for placebo effects,” wrote Simons and colleagues.

Results included:

• The scientific literature cited by the game companies in support of benefits does not include sufficient evidence on the effectiveness of brain games in improving cognition.
• Brain games were shown to trained tasks, but performance on closely related or distantly related tasks and cognitive performance were not significantly improved.
• Many of the published studies did not have proper design or analysis on the efficacy of brain games.
• None of the studies analyzed provided credible evidence of the benefits of brain training.
• The studies lacked information including adequate controls for placebo effects, had sample sizes that were too small and did not fully report and analyze all outcome measures.
• Benefits regarding cognitive training showed a low transfer rate into the improvement of trained tasks.

“In sum, despite a large number of published papers reporting tests of the effects of brain-training interventions, the evidence that training with commercial brain-training software can enhance cognition outside the laboratory is limited and inconsistent. The inconsistency of the results and the pervasive shortcomings in research design and analysis in the published literature undermine scientific backing for some of the claims made by brain-training companies,” concluded Simons and colleagues.