As the number of people living with dementia continues to rise worldwide, researchers are increasingly focusing on one important question: can dementia be prevented or delayed before symptoms begin?
Recent headlines have suggested that brain training may reduce the risk of dementia and even influence biological changes associated with Alzheimer’s disease. These reports have generated considerable interest, particularly following new findings presented at the Alzheimer’s Association International Conference (AAIC) 2026.
While these developments are encouraging, they also raise important questions. Can cognitive training genuinely protect the brain, or are media headlines overstating the evidence?
In this article, we examine the latest research, explain what it means in practical terms, discuss its limitations, and explore what current scientific evidence tells us about reducing the risk of dementia.
Why Dementia Prevention Matters
Dementia affects more than 55 million people worldwide, with Alzheimer’s disease accounting for approximately 60–70% of all cases. As populations continue to age, dementia has become one of the most significant public health challenges of our time.
Although there is currently no cure for Alzheimer’s disease, growing evidence suggests that some cases may be delayed—or potentially prevented—by addressing modifiable risk factors throughout life.
Researchers estimate that up to 45% of dementia cases may be linked to risk factors that can be modified, including cardiovascular health, physical inactivity, smoking, hearing loss, social isolation and educational opportunities.
More recently, scientists have begun investigating whether structured cognitive training could become another valuable component of dementia prevention.
What Is Alzheimer’s Disease?
Alzheimer’s disease is the most common cause of dementia. It is a progressive neurodegenerative condition that gradually affects memory, thinking, language, behaviour and the ability to carry out everyday activities.
Although memory loss is often the earliest symptom, Alzheimer’s disease develops silently for many years before noticeable problems appear. Research suggests that changes within the brain may begin 10 to 20 years before symptoms become apparent.
Scientists have identified two proteins that play a central role in Alzheimer’s disease:
- Beta-amyloid, which forms sticky plaques between brain cells.
- Tau, which forms abnormal tangles inside nerve cells.
These changes gradually disrupt communication between brain cells, eventually leading to cell damage and loss.
However, modern research has shown that Alzheimer’s disease is far more complex than these proteins alone.
A person’s overall risk is influenced by a combination of factors, including:
- Age
- Genetics
- Blood pressure and cardiovascular health
- Diabetes
- Chronic inflammation
- Sleep quality
- Hearing loss
- Physical activity
- Smoking
- Social engagement
- Cognitive reserve
This complexity helps explain why many treatments that successfully reduce amyloid plaques have produced only modest improvements in memory and thinking.
Rather than being caused by a single factor, Alzheimer’s disease develops through the interaction of multiple biological and lifestyle influences over many years.
Can Brain Training Really Help Prevent Dementia?
For many years, commercial brain-training programmes have claimed to improve memory, sharpen thinking and even reduce the risk of dementia.
Unfortunately, most of these claims have not been supported by strong scientific evidence.
Many brain-training games simply help people become better at completing the specific exercises they practise, without improving their ability to function in everyday life. Researchers describe this as “task-specific learning”, rather than genuine improvements in overall cognitive performance.
Because of this, cognitive training has remained controversial.
However, one particular form of training—known as speed-of-processing training—has consistently produced more encouraging results than many commercially available brain-training programmes.
Unlike traditional memory exercises, speed-of-processing training teaches the brain to process visual information more quickly while filtering out distractions. As participants improve, the exercises become progressively more challenging, encouraging the brain to adapt over time.
This approach has been studied extensively in one of the largest and longest-running clinical trials of cognitive training ever conducted.
The ACTIVE Study: One of the Most Important Brain Training Studies Ever Conducted
One of the strongest pieces of evidence supporting cognitive training comes from the Advanced Cognitive Training for Independent and Vital Elderly (ACTIVE) Study, one of the largest and longest-running randomised controlled trials investigating cognitive training in older adults.
The study began more than 20 years ago and enrolled over 2,800 adults aged 65 years and older. Participants were randomly assigned to one of three different cognitive training programmes:
- Memory training
- Reasoning training
- Speed-of-processing training
Unlike traditional memory exercises, speed-of-processing training focuses on improving how quickly the brain recognises, processes and responds to visual information while filtering out distractions. As participants become more proficient, the exercises become progressively more challenging, encouraging the brain to continually adapt.
Because participants were randomly allocated to different training groups, the ACTIVE Study provides a much higher level of scientific evidence than observational studies, where researchers simply monitor people’s lifestyles over time.
The most significant finding emerged during the long-term follow-up.
Researchers found that participants who completed speed-of-processing training, particularly those who attended additional booster sessions, were approximately 25% less likely to receive a diagnosis of dementia over the following two decades compared with those who did not receive the intervention. Interestingly, neither memory training nor reasoning training demonstrated the same long-term benefit.
Although no single study can definitively prove cause and effect, these findings represent some of the strongest evidence to date that targeted cognitive training may contribute to maintaining long-term brain health.
What Did the New ENACT Study Discover?
While the ACTIVE Study showed that speed-of-processing training appeared to reduce the long-term risk of dementia, one important question remained unanswered:
Why does this type of training appear to work?
The recently presented ENACT Study, unveiled at the Alzheimer’s Association International Conference (AAIC) 2026, sought to investigate whether cognitive training might influence the biological processes associated with Alzheimer’s disease itself.
Researchers recruited 53 adults aged over 65 years and randomly assigned them to one of two groups:
- Around 20 hours of structured speed-of-processing training completed over approximately four and a half months.
- A comparison group completing standard computer-based activities, including word-search games.
Rather than assessing thinking skills alone, researchers measured changes in a blood biomarker associated with Alzheimer’s disease. Specifically, they examined the Aβ42/Aβ40 ratio, a blood marker increasingly recognised as being linked to Alzheimer’s pathology.
The findings attracted considerable attention.
Men who completed the speed-of-processing training showed measurable improvements in this Alzheimer’s-related blood biomarker, whereas women did not demonstrate the same biological response.
Interestingly, women still appeared to experience improvements in cognitive performance, suggesting that cognitive training may benefit men and women through different biological mechanisms.
If these findings are confirmed in larger studies, they would represent the first evidence that structured cognitive training can influence an Alzheimer’s-related biological marker, rather than simply improving performance on cognitive tests.
Why Are These Findings Important?
For many years, researchers questioned whether brain training simply helped people become better at completing puzzles and computer exercises without producing meaningful changes within the brain.
The latest findings suggest something potentially much more significant.
Rather than merely improving test performance, repeated cognitive stimulation may encourage the brain to adapt biologically through processes such as:
- Improving neural plasticity
- Strengthening communication between brain networks
- Increasing the brain’s efficiency when processing information
- Influencing the metabolism of proteins associated with Alzheimer’s disease
These possibilities remain under investigation, but they offer an exciting direction for future research.
However, it is equally important to interpret these findings carefully.
The ENACT Study measured changes in blood biomarkers, not direct reductions in amyloid plaques within the brain.
Some media reports suggested that cognitive training could “clear amyloid from the brain”, but this is an oversimplification and is not supported by the available evidence.
Instead, the study demonstrated changes in a blood marker associated with Alzheimer’s disease. Whether these changes translate into reduced plaque formation or lower dementia risk over time remains unknown.
At present, the findings should be viewed as encouraging—but still preliminary.
Why Did Men and Women Respond Differently?
One of the most interesting findings from the ENACT Study was the apparent difference between men and women.
The improvements in Alzheimer’s-related blood biomarkers were observed primarily in men.
This does not mean that women do not benefit from cognitive training. In fact, women participating in the study still demonstrated cognitive improvements.
Instead, the results reinforce growing evidence that Alzheimer’s disease may develop differently in men and women.
Women account for approximately two-thirds of Alzheimer’s disease cases, and researchers increasingly believe that hormonal influences, genetics, inflammation and tau-related changes may play a greater role than amyloid in some women.
These findings highlight an important principle of modern medicine: prevention and treatment strategies may eventually need to become more personalised, recognising that individuals do not all respond to interventions in the same way.
What Are the Strengths of This Research?
From a clinical perspective, there are several reasons why this research deserves attention.
Firstly, the ACTIVE Study provides exceptionally strong evidence because it followed participants for almost 20 years, making it one of the longest-running studies of cognitive training ever conducted. Long-term follow-up is particularly valuable in dementia research, as Alzheimer’s disease develops gradually over many years.
Secondly, both the ACTIVE and ENACT studies used randomised controlled trial (RCT) designs. RCTs are widely regarded as the gold standard in medical research because participants are randomly assigned to different groups, reducing the risk of bias and increasing confidence in the results.
Another important strength is that the ENACT Study moved beyond simply measuring memory or thinking skills. Instead, researchers examined biological markers associated with Alzheimer’s disease, helping to explore how cognitive training may influence brain health rather than simply observing changes in performance.
Taken together, these studies strengthen the possibility that carefully designed cognitive training programmes could become part of future dementia prevention strategies.
However, it is equally important to recognise what these studies do not prove.
What Are the Limitations of the Research?
Although the findings are promising, they should be interpreted with appropriate scientific caution.
One of the biggest limitations is the relatively small size of the ENACT Study, which included only 53 participants, with just 13 men. Such a small sample makes it difficult to know whether the findings would be replicated in larger and more diverse populations.
Another important consideration is that the biomarker findings have, at the time of writing, been presented at a scientific conference rather than published in a peer-reviewed journal. Conference presentations often highlight exciting early findings, but independent peer review remains an essential step before research is incorporated into routine clinical practice.
It is also important to remember that changing a biomarker does not necessarily mean that dementia has been prevented.
Medical research has shown that some treatments can improve laboratory markers without producing meaningful improvements in symptoms or long-term health outcomes. Whether the biological changes observed in the ENACT Study ultimately translate into fewer people developing Alzheimer’s disease remains unknown.
Finally, the intervention studied was a specific structured speed-of-processing training programme delivered under controlled research conditions.
These findings should not be interpreted as evidence that all commercially available brain-training apps, mobile games or online puzzles provide the same benefits.
More research is needed to determine which types of cognitive training are most effective, how often they should be undertaken and who is most likely to benefit.
What Can You Do to Reduce Your Risk of Dementia?
One of the most encouraging aspects of this research is that it reinforces a broader message that has emerged from decades of dementia research: looking after your brain involves much more than one single intervention.
While structured cognitive training may eventually become one component of dementia prevention, it should be viewed as part of a wider strategy that supports lifelong brain health.
Current evidence suggests that the following lifestyle measures may help reduce the risk of dementia:
- Engage in regular physical activity, including aerobic exercise and strength training.
- Maintain healthy blood pressure, cholesterol and blood sugar levels, reducing the risk of vascular disease.
- Treat hearing loss where appropriate, as untreated hearing impairment has been linked to an increased risk of dementia.
- Avoid smoking and limit alcohol consumption, both of which are associated with poorer brain health.
- Prioritise good-quality sleep, as sleep plays an important role in brain repair and the removal of waste products.
- Stay socially connected, maintaining meaningful relationships and participating in community activities.
- Follow a Mediterranean-style diet, rich in vegetables, fruit, whole grains, olive oil, fish and healthy fats.
- Continue learning throughout life, whether through reading, education, hobbies or mentally stimulating activities.
These interventions are supported by a growing body of scientific evidence and remain the cornerstone of dementia risk reduction.
What This Means for Patients
The latest research offers reason for cautious optimism, but it should not be viewed as a breakthrough that changes current clinical practice overnight.
Brain training is not a cure for Alzheimer’s disease, nor can it guarantee that someone will avoid developing dementia.
Instead, the findings suggest that structured cognitive training may become one useful part of a broader approach to supporting healthy brain ageing.
For most people, the greatest benefits are still likely to come from combining several healthy lifestyle habits rather than relying on a single intervention.
Regular exercise, good cardiovascular health, quality sleep, social engagement, lifelong learning and prompt management of medical conditions all play important roles in maintaining cognitive health as we age.
If you are concerned about changes in your memory, thinking or behaviour, it is important to seek a professional assessment. Early evaluation can help identify the cause of your symptoms, provide reassurance where appropriate and ensure that treatment or support is offered as early as possible.
A Consultant Psychiatrist’s Perspective
From a psychiatric perspective, this research is particularly interesting because it brings together two areas that have traditionally been considered separately: cognitive training and the biology of Alzheimer’s disease.
For many years, clinicians have encouraged patients to remain mentally active because observational research suggested that lifelong learning and mentally stimulating activities help build cognitive reserve. Cognitive reserve refers to the brain’s ability to continue functioning despite age-related changes or disease.
The latest findings suggest that, in some individuals, structured cognitive training may influence biological processes associated with Alzheimer’s disease itself. If future research confirms these findings, it could represent an important step towards developing more comprehensive dementia prevention strategies.
However, it is essential to interpret these results responsibly.
At present, there is insufficient evidence to recommend cognitive training as a treatment for Alzheimer’s disease or as a guaranteed method of preventing dementia. Larger studies, longer follow-up and peer-reviewed publications are still needed before clinical recommendations change.
What this research does reinforce is something clinicians have long advised: maintaining an active and engaged brain is likely to be beneficial as part of an overall healthy lifestyle.
For patients, the most practical message is not to search for a single “magic solution”, but to focus on the many lifestyle factors that work together to support long-term brain health.
Key Takeaways
Current research suggests that structured speed-of-processing cognitive training may help support long-term brain health and could potentially reduce the risk of developing dementia in some people.
The recent ENACT Study has also provided early evidence that this form of training may influence blood biomarkers associated with Alzheimer’s disease, although these findings remain preliminary and require confirmation in larger clinical trials.
At present:
- Brain training cannot prevent Alzheimer’s disease on its own.
- Not all brain-training apps or puzzle games have been shown to reduce dementia risk.
- A healthy lifestyle remains the most evidence-based approach to protecting brain health.
- Regular physical activity, cardiovascular health, quality sleep, lifelong learning and social engagement continue to play essential roles in dementia prevention.
- Anyone experiencing persistent memory or thinking difficulties should seek professional assessment rather than assuming symptoms are a normal part of ageing.
As our understanding of Alzheimer’s disease continues to evolve, future research may help identify which cognitive interventions are most effective and who is most likely to benefit from them.
Frequently Asked Questions
Can brain training prevent dementia?
Current evidence suggests that certain structured cognitive training programmes may reduce the risk of dementia, but they should not be considered a guaranteed way to prevent Alzheimer’s disease. Brain training is best viewed as one part of a broader healthy lifestyle.
Are brain-training apps effective?
Some structured cognitive training programmes have shown promising results in clinical research. However, there is currently no evidence that all commercially available brain-training apps provide the same benefits, so it is important to interpret marketing claims with caution.
What is cognitive reserve?
Cognitive reserve refers to the brain’s ability to cope with age-related changes or disease by using existing networks more efficiently or developing alternative pathways. Education, lifelong learning, mentally stimulating activities and social engagement are all thought to contribute to cognitive reserve.
What are the earliest signs of dementia?
Early symptoms may include:
- Memory problems that affect daily life
- Difficulty finding words
- Problems with planning or decision-making
- Becoming confused about time or place
- Changes in mood or personality
- Difficulty completing familiar tasks
These symptoms can have many possible causes, so it is important to seek a professional assessment rather than self-diagnosing.
When should I seek help for memory concerns?
If you or someone close to you notices persistent changes in memory, thinking or behaviour that interfere with daily life, it is advisable to seek a professional assessment. Early assessment can help identify the underlying cause and ensure that appropriate treatment, support and planning are available where needed.
When to Seek Professional Advice
Occasional forgetfulness is common and is not always a sign of dementia. However, if memory difficulties become more frequent, begin affecting daily activities, or are accompanied by changes in thinking, language or behaviour, it is important to seek a professional assessment.
At Oxford Psychiatry Group, our Consultant Psychiatrists provide comprehensive assessments for memory concerns and dementia. We aim to identify the cause of symptoms, offer clear explanations and develop personalised care plans based on each person’s individual needs, strengths and circumstances.
If you are worried about your own memory or that of a loved one, seeking advice early can provide reassurance, clarify the diagnosis and help you access appropriate support.
