Using AI makes you stupid, researchers find

Telegraph

17-06-2025

Artificial intelligence (AI) chatbots risk making people less intelligent by hampering the development of critical thinking, memory and language skills, research has found.
A study by researchers at the Massachusetts Institute of Technology (MIT) found that people who relied on ChatGPT to write essays had lower brain activity than those who used their brain alone.
The group who used AI also performed worse than the 'brain-only' participants in a series of tests. Those who had used AI also struggled when asked to perform tasks without it.
'Reliance on AI systems can lead to a passive approach and diminished activation of critical thinking skills when the person later performs tasks alone,' the paper said.
Researchers warned that the findings raised 'concerns about the long-term educational implications' of using AI both in schools and in the workplace.
It adds to a growing body of work that suggest people's brains switch-off when they use AI.
'Human thinking offloaded'
The MIT study monitored 54 people who were asked to write four essays. Participants were divided into three groups. One wrote essays with the help of ChatGPT, another used internet search engines to conduct research and the third relied solely on brainpower.
Researchers then asked them questions about their essays while performing so-called electroencephalogram (EEG) scans that measured activity in their brains.
Those who relied on ChatGPT, a so-called 'large language model' that can answer complicated questions in plain English, 'performed worse than their counterparts in the brain-only group at all levels: neural, linguistic, scoring', the researchers said.
The EEG scans found that 'brain connectivity systematically scaled down with the amount of external support' and was weakest in those who were relying on AI chatbots to help them write essays.
The readings in particular showed reduced 'theta' brainwaves, which are associated with learning and memory formation, in those using chatbots. 'Essentially, some of the 'human thinking' and planning was offloaded,' the study said.
The impact of AI contrasted with the use of search engines, which had relatively little effect on results.
Of those who has used the chatbot, 83pc failed to provide a single correct quote from their essays – compared to around 10pc in those who used a search engine or their own brainpower.
Participants who relied on chatbots were able to recall very little information about their essays, suggesting either they had not engaged with the material or had failed to remember it.
Those using search engines showed only slightly lower levels of brain engagement compared to those writing without any technical aides and similar levels of recall.
Impact on 'cognitive muscles'
The findings will fuel concerns that AI chatbots are causing lasting damage to our brains.
A study by Microsoft and Carnegie Mellon, published in February, found that workers reported lower levels of critical thinking when relying on AI. The authors warned that overuse of AI could leave cognitive muscles 'atrophied and unprepared' for when they are needed.
Nataliya Kosmyna, the lead researcher on the MIT study, said the findings demonstrated the 'pressing matter of a likely decrease in learning skills' in those using AI tools when learning or at work.
While the AI-assisted group was allowed to use a chatbot in their first three essays, in their final session they were asked to rely solely on their brains.
The group continued to show lower memory and critical thinking skills, which the researchers said highlighted concerns that 'frequent AI tool users often bypass deeper engagement with material, leading to 'skill atrophy' in tasks like brainstorming and problem-solving'.
The essays written with the help of ChatGPT were also found to be homogenous, repeating similar themes and language.
Researchers said AI chatbots could increase 'cognitive debt' in students and lead to 'long-term costs, such as diminished critical inquiry, increased vulnerability to manipulation, decreased creativity'.
Teachers have been sounding the alarm that pupils routinely cheating on tests and essays using AI chatbots.
A survey by the Higher Education Policy Institute in February found 88pc of UK students were using AI chatbots to help with assessments and learning and that 18pc had directly plagiarised AI text into their work.