See more Daily Mail on Google -save us as a Preferred Source It’s fair to say the AI revolution is well and truly under way in homes, schools, universities and businesses across the UK.
At least one billion people have downloaded the AI app ChatGPT since its launch in 2022, for instance, and millions more use rival products for everyday activities ranging from researching information and advice to writing and summarising reports.
But what are the implications for human health from relying on machines to do the hard mental graft for us, instead of using our brains?
Some research already shows that students who use AI to help them ‘learn’ new topics, or put together projects, retain less of that information than peers who trawl through the research evidence for themselves, deciding what to include and what to leave out.
This is potentially important as repetitive learning, such as reading complex information time and again to make sure you understand it, is vital for maintaining the brain’s neuroplasticity – its ability to keep forming new connections between nerves.
And the brain’s ability to constantly ‘rewire’ itself in response to difficult mental tasks helps build ‘cognitive reserve’ – a buffer that means normal mental function can be retained longer – and can protect the brain against the ravages of dementia.
It’s the reason why experts often recommend taking up mentally demanding activities, such as learning a new language, to reduce the risk of the condition, which affects around one million people in the UK – a figure expected to rise to 1.4 million by 2040 due mainly to an ageing population.
Now some experts are warning that a growing over-reliance on AI for what’s being termed ‘cognitive off’ – or delegating even the most remotely challenging mental chores to AI algorithms, such as summarising a document or drafting an email – could be putting millions more people at even greater risk of dementia.
At least a billion of us have downloaded the AI app ChatGPT... but over-reliance on artificial intelligence could be putting more of us at risk of developing dementia, warn experts
As Simone Rossi, a professor of neurology at the University of Siena in Italy, explains: ‘Habitual over-reliance on AI may reduce our cognitive exercise [i.e. the amount we use our brains to process information], and that is something we in neuroscience take very seriously because, in the long term, such a passive attitude may weaken the brain’s neuroplasticity.’
In January, Professor Rossi and colleagues published a report in the journal Artificial Intelligence warning that the increasing dependence on AI in everyday life (some estimates say adults now spend up to seven hours a day interacting with AI software) is a direct threat to our brain function. They wrote: ‘Neuroplasticity is foundational to development, learning, memory, healthy ageing and possibly even human intelligence capabilities.
‘We argue that passive, uncritical reliance on AI may weaken that activity-dependent plasticity and erode human cognition.’
One of the first studies to highlight this effect was published last year in the Journal of Computer Science.
It was carried out by research scientist Nataliya Kosmyna at Massachusetts Institute of Technology, who noticed her computer studies students appeared to be forgetting things they had learned much more quickly than previous cohorts.
She suspected they were ‘cognitively off’ much of their work to AI algorithms, so set up an experiment to explore whether this was the case.
Around 50 students were instructed to write a short essay – one group using ChatGPT; one using Google search without AI; and one using no technology at all (just books, lecture notes or academic journals).
Each volunteer underwent an electroencephalography (a scan of the brain’s electrical activity) as they worked.
Research scientist Nataliya Kosmyna noticed her students were forgetting things more
Results showed those using no technology had scans that appeared extremely active (or ‘on fire’, as researchers later described it) across many parts of the brain, indicating that it was working hard to digest and process information.
Those using Google search engine only showed high levels of activity in parts of the brain associated with visual stimulation.
And those using ChatGPT had the least activity of all – 55 per cent lower than the non-technology group. Nataliya Kosmyna said ‘the brain didn’t fall asleep, but there was much less activity in areas corresponding to creativity and processing of information’.
And there was worse to come. Days after submitting their essays, most of the AI group were barely able to quote anything from it – suggesting the brain had memorised nothing.
Four months later, when the same ChatGPT group were told to write another essay – but without AI this time – scans showed their neural connectivity (the extent to which their brain cells were activated during the learning process) was lower than in their peers who did it that way first time round, suggesting the capacity to store new information had been jeopardised longer term.
Similar findings emerged from a 2025 study at the Federal University of Rio de Janeiro in Brazil, where 120 students were split into two groups.
Each group was told to spend two weeks researching an assignment – one using ChatGPT, the other more traditional resources – and give a presentation on it. Researchers then surprised the recruits with a spot-check on how much of their assignment they could recall six weeks later.
Barbara Sahakian predicts it is ‘highly likely’ that widespread AI use will lead to more cases of dementia
The results, published in the journal Social Sciences and Humanities Open, revealed that those who used traditional resources correctly answered
68.5 per cent of questions about their presentation; in the ChatGPT group, it was 57.5 per cent.
The biggest negative effect was when students were asked to study technical topics where the learning materials were difficult to understand. More of the details had been engrained on the memories of those who did not use AI. This is thought to be partly because putting in the effort to understand something and spending longer with a topic helps the brain store the information into longer term memory.
Meanwhile, in May, the Department for Education in England issued new guidance to schools warning them of the dangers of pupils using AI for doing homework and school projects.
It warned that cognitive off in the classroom could stop children from developing independent thinking and from mastering the subjects they are being taught.
But it’s not just students’ brains that may be harmed by delegating work to AI algorithms.
A 2025 study in The Lancet Gastroenterology and Hepatology reported how doctors who used AI – running scan images through an algorithm – to screen for bowel cancer were subsequently worse at spotting tumours themselves when they did it manually.
But does this all really mean that everyday use of AI could put us at increased risk of dementia later in life?
The technology is still so new that no long-term studies have yet shown this is the case. But some leading experts fear the risk is genuine.
Barbara Sahakian, a professor of clinical neuropsychology at Cambridge University and author of the book Brain Boost: Health Habits for a Happier Life, predicts it is ‘highly likely’ that widespread AI use will lead to more cases of dementia.
‘You have to drive those neural circuits in the brain in order to keep it working for longer and reduce the risk of dementia,’ she says. ‘If you are not participating in cognitively stimulating activities and just using AI then you will go downhill.’
Studies show, for example, that using GPS to navigate on car journeys switches off parts of the brain associated with learning and memory. But there’s no evidence GPS use raises the risk of dementia as the cognitive off involved only occurs when we are driving. The difference with AI is that it is encroaching on almost every aspect of daily life – relieving our brain of much of its everyday workload.
‘The brain needs to be exercised – use it or lose it,’ says Aimee Spector, a professor of the clinical psychology of ageing at University College London.
‘Using AI constantly instead of trying to come up with solutions or work things out ourselves could increase the risk of dementia. It’s important to note that, for many people, AI is a positive development – we just need to use it in the right way; as a support, not as a permanent crutch.’
She adds: ‘The brain needs to be active and to have lots of social interaction and if we become AI dependent, there is a risk we will lose that.’