Brain training has been touted as a way to prevent age-related cognitive decline. Many products are available for purchase. But are any actually effective?
We reviewed the merits of peer-reviewed clinical intervention studies that investigated commercial computerised brain training products in healthy people aged over 50 years.
Exercises from BrainHQ continuously adjusted difficulty depending on how the user was performing. One set of exercises included matching pairs of confusable syllables, reconstructing sequences of verbal instructions, and identifying details in a verbally presented story.
Other sets of exercises are visually engaging – for example, in one of the exercises the user is assumed to be a gardener. To grow plants, the user has to match pictures after they appear briefly on screen, one after the other.
Exercises from Cognifit contain 21 different tasks. In one of the tasks a hot-air balloon flies in the sky. On its way, it lands on different clouds. The user has to remember and reproduce its exact route.
In another task, a letter grid appears in the centre of the screen. A picture of a well-known object appears in the lower left corner of the screen and the user has to find the name of this object spelled out in the letter grid.
Overall, both programs provided reasonable clinical evidence to support healthy brain ageing. Healthy brain ageing is a broad term that focuses on sustaining cognitive function and capacity to function independently as we age.
Less than 40% of programs come with evidence
To determine if particular brain training exercises are effective, it’s important to look at the scientific evidence behind these exercises and the purpose for which they are recommended (for example, to promote healthy brain ageing, or for dementia or other neurological diseases), and to understand the principle behind the design of such exercises.
We identified 18 computerised brain training programs available across the world that were marketed with scientific claims. Of these, only seven programs (less than 40%) had been assessed by peer-reviewed studies that reported formal outcome measures of the programs on specific cognitive domains such as memory, reasoning, processing speed and executive functions. We selected studies that had been conducted in healthy adults, aged at least 50 years.
Trials were regarded as “well designed” if they were randomised clinical trials with a control group. They were classified as being of high, moderate or poor quality as rated from one to ten on a checklist. Trials with a score greater than six are deemed high quality; trials with scores between five and six are moderate quality; and those with a score less than five are poor quality.
We classified the seven computerised brain training programs into three categories according to the strength of the evidence supporting their claims of efficacy. This process included an examination of the quantity and quality of the clinical trial applied in each instance.
Programs in this category had at least two well-designed randomised controlled trials, one of which was of high-quality design. Two brain training programs met these criteria (BrainHQ and Cognifit).
Programs in this category were supported by only one randomised controlled trial of high-quality design. Three programs were classified at this level (Cogmed, BrainAge 2 and My Brain Trainer).
Programs in this category were supported by only one randomised controlled trial of moderate or poor design. Two were rated at this level (Dakim and Lumosity).
Our findings indicate some computerised brain training programs are backed by evidence in their claim to assist in promoting healthy brain ageing. However, such programs must be further validated using brain imaging methods to investigate their mechanism of action.
How to pick an effective program
Brain training programs feature different exercises that particularly target specific cognitive domains such as memory, reasoning, speed of processing, and executive functions. Effective exercises are mostly designed on the principle of the brain’s capability to rewire and reconnect – the neuroplasticity principle. Such computerised exercises are adaptive according to a person’s capability, continuously challenging and audio and/or visually interactive.
Some features to look for in deciding whether a program is right for you include:
the program is recommended for your specific purpose – for example, healthy brain ageing, rehabilitation, learning and concentration
the program is scientifically validated
the program is adaptive and engaging
the program is continuously challenging
the program features audio and/or is visually interactive
the program provides feedback about your progress.
Programs that train the brain to be more responsive using specific tasks and increasing levels of difficulties are thought to help rewire neural pathways according to the neuroplasticity principle.
Identifying problems least likely to work
In our review process, we identified 18 brain training programs. Of these, 11 had no clinical trials or empirical evidence to indicate they were effective in promoting healthy brain ageing.
To spot the programs without adequate evidence, one option is to go to the program’s website and identify whether the company provides links to specific studies relevant to your purposes.
Most of the websites provide only supportive evidence – that is, they do not refer to specific clinical trials, but instead quote the principles of the brain’s ability to rewire or reconnect, or cite studies that used other programs. Very few have a list of studies that directly measured the impact of the program in question.
Findings from studies that are randomised, double-blinded (both the investigator and the user don’t know if the intervention is real or only a placebo) and have a control group that meets the gold standard of clinical trials are more reliable than non-randomised trials without any control conditions.
Training programs to prevent cognitive decline
However, evidence concerning how or where these software programs affect plasticity in brain cells or connections within the brain is lacking. Assessments using specific biological markers of Alzheimer’s disease (or other neurodegenerative diseases) such as blood and brain imaging would considerably enhance clinical validation of brain training programs. This would also enable greater understanding of the connection between computerised brain exercises and human cognition, and provide an insight into new therapeutic pathways.
It’s possible computerised exercises that are adaptable and continuously challenging may help the brain to rewire lost connections that are linked with dementia later in life. At the moment, however, there is little evidence computerised brain training programs can help prevent dementia onset. Thus, more longitudinal follow-up studies are required.
Regardless of whether new neural pathways are established, some mental exercises may work simply by increasing the blood circulation in the brain, similar to physical exercise. Thus, healthy brain ageing may be achieved by maintaining or improving cognitive functions via avenues such as brain training, but also through social interaction, exercise, diet and other lifestyle strategies.