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Brain Training: Show Me the Evidence!

Brain Training: Show Me the Evidence!

By Tejal M. Shah & Ralph N. Martins

Many computer-based brain-training programs promise to improve cognitive capacity and delay age-related issues such as Alzheimer’s disease, but how credible is the evidence behind these claims?

Despite greater efforts to maintain brain function well into late life, the challenge of helping older adults to maintain or improve memory, judgement, learning, executive functions and processing speed remains a challenge. The high prevalence of age-related degenerative diseases such as Alzheimer’s disease makes the need to resolve this challenge more pressing. A 5-year delay in the onset of Alzheimer’s disease can save Australia $13.5 billion by 2020 and $67.5 billion by 2040. As drug trials have been ineffective to date, attention has been directed towards lifestyle strategies and interventions that prevent or delay the onset of neurodegenerative diseases.

Among these approaches is evidence-based research into the use of computerised brain-training software, which has spawned a multi-billion dollar computer-based brain health and fitness industry that claims it can promote and maintain healthy brain ageing. However, most of the software programs often lack the supportive data required to validate their efficacy. We have therefore conducted a review to help give clinicians guidance when advising their patients and to help consumers decide which programs are strongly evidence based and therefore more likely to be beneficial for healthy brain ageing.

We scrutinised 26 peer-reviewed studies that examined the effectiveness of seven computerised brain-training programs for healthy older adults aged over 50. We found that at least some of the commercially available brain-training programs can promote healthy brain ageing.

Grading Brain-Training Programs

We looked at the scientific evidence behind these exercises and the purpose for which they are recommended (e.g. to promote healthy brain ageing, or for dementia or other neurological diseases) and the principle behind the design of such exercises. We focused our investigation on studies directed at healthy brain ageing. We identified 18 computerised brain-training programs that claimed to have scientifically proven benefits. We found that 11 of the programs had no clinical trials or empirical evidence, demonstrating that their claims of effectiveness were not scientifically proven. The products of the remaining seven companies were then classified into three categories based on the strength of the evidence of their effectiveness. We assessed both the quantity and quality of clinical studies.

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 check list. Trials with a score greater than six are deemed high quality; trials with scores between five and six were rated as moderate quality; and those with a score less than five were considered as poor quality.

  • Level 1 programs had at least two well-designed randomised controlled trials, one of which had to be of high quality. The brain-training programs BrainHQ and Cognifit met the criteria for Level 1.
  • Level 2 programs had only one high-quality randomised controlled trial. Cogmed, BrainAge 2 and My Brain Trainer were classified in Level 2.
  • Level 3 had only one moderate/poorly designed randomised controlled trial. Dakim and Lumosity were in Level 3.

Programs that were rated as Level 1 (BrainHQ and Cognifit) mainly involved exercises that were auditory and/or visually stimulating and were used in the clinical trials. For example, in one of the auditory stimulation exercises, the user is required to listen to a sound frequency sweep that begins low and rises upward or begins high and then descends, and then determine whether they go up or down. Another exercise required users to identify a synthetically generated syllable (e.g. “ba”) from a confusable pair (e.g. “ba” vs “da”), whereas some other exercise involved identifying details in a verbally presented story.

Other sets of exercises involve visual engagement. For instance, during a road tour exercise, the user stops to see roadside attractions. However, to reach them the user must spot cars in the centre of their vision while also identifying road signs on the edges of the screen. Overall, the difficulty level increases if the user performs the exercises correctly, but the difficulty level is decreased if the user performs the exercises incorrectly.

In one of the Cognifit exercises named Morning Time, windows are arranged randomly on a screen and are opened momentarily, one after the other. The task is to follow the exact sequence in which the windows were opened. The task evolves as the user remembers longer sets. This task is designed to train memory.

Thus, in order for the brain to be exercised effectively, the activities are required to be novel, well-tailored to the individual, and continuously challenging. Programs that currently lack supportive evidence may also be effective, given that they are mostly based on the same neuroplasticity principle. However, they could target specific cognitive domains, and thus need to be empirically validated in independent clinical studies.

Features of Effective Brain-Training Programs

Brain-training programs feature different exercises that target specific cognitive domains such as memory, reasoning, processing speed and executive functions. Many effective exercises are designed according to the principle of the brain’s capability to rewire and reconnect – the neuroplasticity principle. An exercise must be 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 whether the program:

  • is recommended for your specific purpose, such as healthy brain ageing, rehabilitation, learning and concentration;
  • is scientifically validated for your specific purpose;
  • is adaptive and engaging;
  • is continuously challenging;
  • features audio and/or is visually interactive; and
  • 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.

Brain Training Benefits

There is now sufficient evidence to support the notion that the human brain is plastic in later life and can benefit from properly designed brain-training programs. 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. However, whether computerised brain-training programs can help prevent dementia onset remains to be determined. Thus, longitudinal prevention clinical trials are needed to address this important question.

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 markers and brain imaging would considerably enhance clinical validation of brain-training programs and assist in addressing whether these programs actually promote neuroplasticity. This would also enable greater understanding of the connection between computerised brain exercises and human cognition, and provide an insight into new therapeutic pathways.

Regardless of whether new neural pathways are established, some mental exercises may work simply by increasing 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. However, for optimal brain health a holistic approach incorporating lifestyle strategies needs to be undertaken which include social interaction, exercise, diet and sleep.

Tejal M. Shah is a Research Fellow at Macquarie University. Ralph N. Martins is Director of the Centre of Excellence for Alzheimer's Disease Research and Care at Edith Cowan University, and Professor of Neurobiology at Macquarie University.