Your Brain on ChatGPT: What a New MIT Study Tells Us About the Cost of Convenience
A few years ago, the conversation around AI in education was full of possibility. Better access, personalised support, or an escape from the discomfort of starting from scratch. But a new study from MIT suggests we might want to consider not just what AI gives us but what it might be taking away.
In a controlled study, researchers at the MIT Media Lab asked participants to write essays using either ChatGPT, a search engine, or nothing at all. EEG scans tracked their brain activity as they worked. Afterward, participants were asked to recall their writing, reflect on the process, and rewrite one of their essays. This time using a different method.
The findings are sobering, to say the least.
What They Found
Participants of the brain-only group exhibited the richest and most distributed brain activity, retained more information, and reported a stronger connection to their work. Their writing also showed more variation and originality.
Those who used search engines performed slightly lower, but still showed signs of active engagement.
And then there was the ChatGPT group, who showed significantly lower brain connectivity across all EEG bands. That means reduced activity in regions tied to memory, creativity, semantic processing, and attentional control. They also:
Couldn’t accurately quote their own work
Expressed less ownership and satisfaction with their writing
Were more likely to defer entirely to the AI by session three
Over time, their approach became more passive. By the final sessions, many simply copied and pasted AI output with minimal edits. Their essays, while competent, were strikingly similar, described by human graders as “soulless.”
Even more concerning, when the ChatGPT group was later asked to write without the tool, their brains didn’t fully “switch back on.” Prior reliance appeared to lessen engagement even after the tool was removed.
Convenience Always Has a Cost
The researchers call this cognitive debt - the accumulated loss of critical engagement when a tool does too much of the thinking for us.
The term feels apt. Like financial debt, it accumulates quietly. You might not notice its presence until you're asked to do the thinking yourself, and you find the skills are no longer there.
The study tells us that when we use tools like ChatGPT frequently, our capacity to re-engage weakens. The neural activity of ChatGPT users didn’t simply bounce back when they switched to writing without it. The mental effort required had already been externalised.
The brains unable to “recover” suggest something alarming.
Tool use changes the user.
There is no neutral stance. You don’t just “use AI”, it reshapes your habits. It alters your thresholds for boredom, uncertainty, ambiguity. It teaches you, implicitly, what kind of mental effort is optional.
So What Does This Mean?
It means we should be paying closer attention to how we use these systems and not just how well they perform.
There’s a difference between writing and composing. Between generating text and understanding it. Between information and memory. And these differences matter! Especially in education, where the goal is not the product, but the learning.
It also means that some forms of difficulty - the struggle to phrase something, to recall an idea, to structure a thought - are not inefficiencies. They are the very processes through which memory and understanding are built.
Remove the struggle, and you remove the learning too.
The Question Is No Longer “Can AI Help Us Think?”
But what happens when it thinks instead?
AI isn’t going away. Nor should it. But we’re at a point where how we use these tools could be training a generation to disengage. This MIT study is a reminder that cognitive effort… the sometimes frustrating, often messy work of thinking is not a bug in the system. It’s the whole point.
Other questions include What does "learning" mean when it no longer requires effort? What happens to our sense of ownership when the ideas come from somewhere else? Are we training our brains to avoid the very tasks that make them grow?
Yes, ChatGPT might help you finish your draft faster. But if you can’t remember what you wrote or why, it’s worth asking what exactly was gained. Or lost.
And whether the next time you sit down to write, you'll be the person who used to know how.
Study: Kosmyna, N. et al. (2025). “Your Brain on ChatGPT: Accumulation of Cognitive Debt when Using an AI Assistant for Essay Writing Task.” MIT Media Lab.
Available via: www.brainonllm.com
