Commercial Brain Training Device Reduces Working Memory

Laura Steenbergen, MSc., PhD Candidate Cognitive Psychology at Institute of Psychology Leiden Interview with:
Laura Steenbergen, MSc., PhD Candidate
Cognitive Psychology at Institute of Psychology
Leiden University 

Medical Research: What is the background for this study? What are the main findings?

Response: A recent initiative supported by several eminent research institutes and scientists calls for a more critical and active role of the scientific community in evaluating the sometimes far-reaching, sweeping claims from the brain training industry with regard to the impact of their products on cognitive performance. tDCS is a noninvasive brain stimulation technique that has developed into a promising tool to boost human cognition. Previous studies using medical tDCS devices have shown that tDCS promotes working memory (WM) updating in healthy individuals and patients. The aim of the current study was to investigate whether the commercial tDCS headset (v.1), which is easily and freely available to anyone in the world, does in fact improve cognitive performance, as advertised in the media. Results showed that active stimulation with the commercial device, compared to sham stimulation, significantly decreased working memory performance. The device we tested is just one example of a commercial device that can easily be purchased and, without any control or expert knowledge, used by anyone. The results of our study are straightforward in showing that the claims made by companies manufacturing such devices need to be validated. Even if the consequences of long-term or frequent use of the device are yet to be demonstrated, our findings provide strong support the important role of the scientific community in validating and testing far reaching claims made by the brain training industry.

Medical Research: What should clinicians and patients take away from your report?

Response: Clinicians should warn patients for potential risks and advise them to operate with the regulations that do exist, such as never to exceed the stimulation time of 20 minutes a day and to always use a low current. Our results suggest that the use of a commercial device can actually be detrimental (despite what is advertised in the media) and, as such, cannot be regarded an alternative to medical devices that are used by professionals (the use of which has been demonstrated to be successful in promoting WM). Patients should therefore always seek assistance of a professional with sufficient knowledge about the device and its effects.

Medical Research: What recommendations do you have for future research as a result of this study?

Response: We hope the scientific community will become more active in validating and testing such commercial devices, that are easily and freely available to anyone, and can be used without any regulation or expertise yet are possibly harmful to the people using them.


Laura Steenbergen, Roberta Sellaro, Bernhard Hommel, Ulman Lindenberger, Simone Kühn, Lorenza S. Colzato. “Unfocus” on commercial tDCS headset impairs working memoryExperimental Brain Research, 2015;
DOI: 10.1007/s00221-015-4391-9

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Laura Steenbergen, MSc., PhD Candidate (2015). Commercial Brain Training Device Reduces Working Memory