New findings from the world’s first randomized controlled trial investigating interventions against dementia suggest that cognitive “speed training” can significantly lower the odds of receiving a dementia diagnosis, potentially by as much as 25 percent.
Marilyn Albert, from Johns Hopkins University School of Medicine in Baltimore, Maryland, expressed enthusiasm for the study’s outcome, stating, “There was a lot of skepticism about whether or not brain training interventions were beneficial, and to me, [our study] answers the question that they are.”
A History of Controversy in Brain Training
The field of brain training has been mired in controversy for years. Initial excitement surrounding these interventions began to fade after several companies were found to be exaggerating the benefits of their brain-training products, which they claimed offered protection against cognitive decline.
In 2014, a significant dispute emerged when nearly 70 scientists co-signed an open letter asserting a lack of conclusive evidence that brain training programs yielded practically relevant changes or genuinely promoted brain health. This viewpoint was later challenged by another open letter, signed by over 100 scientists, which countered these arguments.
A Twenty-Year Study Offers New Insights
However, a comprehensive 20-year study involving 2832 individuals aged 65 and older now presents compelling evidence that specific cognitive exercises may indeed offer tangible benefits.
Participants in the study were randomly allocated to one of three distinct intervention groups or to a control group. One group underwent speed training, engaging with a computer-based task known as Double Decision. This exercise involved briefly presenting a car and a road sign within a scene before their disappearance. Participants were then required to recall the specific car that appeared and its location relative to the sign. The task was designed to adapt, increasing in difficulty as the participant’s performance improved.
The remaining two groups focused on memory or reasoning training, learning strategies specifically developed to enhance these cognitive skills.
Training Regimen and Follow-Up
Participants completed two sessions per week, each lasting between 60 and 75 minutes, for a duration of five weeks. Subsequently, approximately half of the individuals within each group were randomly selected to receive booster sessions. These consisted of four additional one-hour sessions administered at the end of the first year and another four at the end of the third year.
After a period of twenty years, researchers meticulously examined US Medicare claims data. Their objective was to ascertain the number of participants who had received a diagnosis of dementia.
Remarkable Results from Speed Training
The findings revealed that individuals who completed the speed training program, particularly those who received booster sessions, exhibited a 25 percent lower risk of being diagnosed with Alzheimer’s disease or a related dementia when compared to the control group. Notably, no other group, including those who underwent speed training without the booster sessions, demonstrated a statistically significant change in dementia risk. Albert described the magnitude of this effect as “really quite astonishing.”
Torkel Klingberg, from the Karolinska Institute in Stockholm, Sweden, commented on the study, stating, “The analysis seems rigorous. It is impressive to have a 20-year follow-up, and reducing the risk score for dementia is an impressive and important result.”
Interpreting the Findings with Caution
Walter Boot, at Weill Cornell Medicine in New York state, urged a cautious approach to interpreting the results. He pointed out that the research team assessed numerous outcomes over the two-decade period, including mental health indicators. Boot explained, “The more outcomes that are examined and the more statistical tests that are conducted, the greater the likelihood that at least one result will look meaningful, even if the intervention itself had no true impact.” He clarified that this perspective does not invalidate the findings but emphasizes the need for careful interpretation.
Potential Mechanisms Behind Speed Training’s Efficacy
The precise reasons why speed training might be effective remain somewhat unclear. One leading hypothesis centers on its reliance on implicit learning, a form of learning that occurs subconsciously, without conscious awareness. Albert noted, “We know that changes that occur from this kind of learning are very long-lasting.” Furthermore, she highlighted that despite the relatively short duration of the training, the task itself was demanding. “You really have to pay attention, and it gets harder if you do it well,” she added.
Etienne De Villers-Sidani, from McGill University in Montreal, Canada, drew parallels with other instances where brief experiences can lead to enduring changes in the brain, citing a single car crash as an example that can instill a lifelong fear of driving.
He proposed that speed training might contribute to building “brain reserve,” essentially a cognitive buffer that can protect against damage. According to this concept, if cognitive function begins to decline at a certain threshold of brain damage, individuals with a more robust brain, characterized by a greater number of neurons and connections, would likely experience this decline at a later stage.
Brain Connectivity and its Role
Albert further suggested that enhanced brain connectivity could facilitate individuals’ ability to divide their attention more effectively. This improved attentional control could make navigating the complexities of daily life easier as people age. Such improvements, in turn, might lead to reduced social isolation, encourage greater activity levels, and foster increased social engagement – all factors known to contribute to long-term brain health.
Dose-Dependent Effects and Future Research
The study’s authors also posited that the positive outcomes observed in the booster group could indicate a dose-dependent effect of speed training. Bobby Stojanoski at Ontario Tech University emphasized the importance of future research focusing on this aspect, asking, “What is the optimal amount of training?”
Andrew Budson, from Boston University, offered a concluding thought, emphasizing that the primary takeaway message is not an imperative for everyone to engage solely in computer-based speed training games. Instead, he suggested that activities which utilize implicit learning may indeed play a beneficial role in delaying the onset of Alzheimer’s disease symptoms. Budson concluded, “Learning a new sport, vocation or craft is likely to produce long-lasting [beneficial] changes in the brain, in addition to any enjoyment you derive from engaging in these activities.”