AI Can Make You Stupid: 5 Ways to Use It (and Get Smarter)

What a new MIT study reveals about your brain on ChatGPT and how to use AI without losing your edge.

AI stands between us and ourselves. Will it spark or block our thinking?

A new study from MIT Media Lab suggests something we suspected all along: using large language models like ChatGPT may be making us stupid. You may have seen the headline reactions: alarmist takes, smug I-told-you-sos, and sarcastic eye-rolls.

But this isn’t just another round of AI noise. It’s a signal and a serious one. If you’re someone who values the ability to think clearly, here’s the uncomfortable truth:

AI isn’t the problem. The way we use it is.

Your Brain on AI

The study asked 54 participants, aged 18 to 39, to write multiple essays using one of three methods:

1. No tools, just their brain

2. Google Search

3. ChatGPT

Meanwhile, EEG headsets tracked activity across 32 brain regions. The result? The ChatGPT group had the lowest brain engagement. Over time, their essays got simpler, their vocabulary flatter, their thinking lazier. Worse still, they remembered less and reported feeling little ownership of what they wrote.

The Long Decline Nobody’s Talking About

This isn’t just about ChatGPT. It echoes something we’ve observed: a slow reduction in our ability to reason.

According to Norwegian researchers, global IQ scores have been falling since 1975, reversing nearly a century of growth. The scientists argue it’s not genes but our environment: changes in education, attention, media, and tech. In a 2017 study, researchers found that just having a smartphone visible on a desk impaired cognitive performance, even when it wasn’t being used.

AI isn’t just another tool. It’s the latest layer in the world’s largest, unregulated experiment on the human brain. No one has yet measured the long-term impact. But you might already be feeling it.

The Fork in the Road: Thoughtless or Thoughtful AI Use

The AI genie isn’t returning to its bottle. The question isn’t whether you’ll use AI. It’s how.

Will you let it replace your thinking or enhance it?

This isn’t just about productivity. It’s about your capacity to think, to learn, to know.

5 Ways to Use AI and Get Smarter

1. Lead With Your Brain, Not the Bot

Start by thinking deeply: write a rough draft, sketch ideas, or map your structure. Then, use AI to test, extend, or sharpen it. Think about it like this:

Brain then LLM help = smarter.

LLM then Brain = slippery slope.

A good test I use: do I have a hypothesis or point of view before using AI?

2. Read Longform. Often.

We’re being rewired for snippets. Fight back with books, essays, and deep articles. Long-form reading stretches your attention span and your thinking. Use a focus timer and turn off notifications. Protect your attention span like it matters - because it does.

3. Write. Then Rewrite.

“There is no such thing as good writing, only good rewriting.” I’ve seen this wisdom attributed to everyone from wartime poet Robert Graves to my favourite teenage author, Stephen King. It argues writing is thinking. The first draft forces you to think. The second draft helps you judge. Don’t just prompt and paste. Engage. Struggle. Shape your thinking.

4. Develop Your Taste for What Resonates

Don’t just ask: Is this correct? Ask: Is this me? Does this move me? Is this genuinely interesting? If not, keep going.

5. Use AI as a Copilot, Not the Pilot

Here are the five levels of Human-AI partnership:

Level 1: Do it for me

Level 2: Help me do it

Level 3: Help me think it through

Level 4: What might I be missing?

Level 5: Push back on my thinking

Most people stop at Level 1. Go further. Ask AI to challenge you, not just assist you.

The best conversation I’ve had so far with ChatGPT was after I uploaded several of my Forbes and Substack articles and asked: “Tell me something I don’t know about myself as a writer.”

Another favourite prompt: “Please don’t rewrite my work; I want you to challenge the ideas I’ve presented. Switch off your tendency to flatter me.”

Cognitive Debt Is Real

In the study, researchers introduced the idea of cognitive debt: the intellectual equivalent of eating junk food. Quick. Convenient. But over time, it can be corrosive.

Over dinner a few weeks back, the son of a friend - a 2nd year psychology student at a top UK university - told me almost all his peers are now using ChatGPT for essays. When I asked if he felt he understood the material as well, he paused and his anxious, honest self-awareness surprised me.

“I don’t think I understand the course as well as I would have,” he said. “But I don’t know for sure. Because everybody is using AI, I don’t have the opportunity to do my degree without it.”

Academic reform is not the subject of this post. But it’s not surprising that some universities are now bringing back the ancient tradition of viva voce (Latin, translates as “word of mouth”). These are live interviews to more accurately test students' knowledge. More urgent change must follow.

AI isn’t inherently evil. It’s worth remembering, though, that it is an industrial-sized parrot, pecking at the mountainous scrapings from the World Wide Web. Without a clear point of view, we risk becoming parrots ourselves: mimicking the mimic, confusing instant access with understanding.

Here’s a chilling thought: What if we’re not just losing sharpness temporarily but surrendering it permanently? Two English teachers who assessed the essays in the MIT study called them largely “soulless.” But this isn’t just about losing an intellectual edge. How will you begin to feel about yourself if you continually present ideas that aren’t yours?

What is the emotional cost of becoming…fake?

Self-Test: Cognitive Debt

Ask yourself:

1. Did I form an idea before prompting AI?

2. Can I clearly remember what I wrote?

3. Did I challenge and rewrite - or accept the first output?

4. Does this sound like me, or a generic “internet voice”?

If you answered no to two or more… you might be building cognitive debt.

The MIT researchers focus their concern on students trying to learn. So my leadership clients – mostly Gen Xers in top jobs – can relax, right? I don’t think so. In our fast-moving, uncertain world, we all need to stay switched on whether it’s writing a new business strategy, drafting a message to our colleagues or attempting to innovate processes and products.

So what now?

When technology removed our arms and legs from the production process, it took us over a century or more to invent aerobics, jogging, and kettle bells to stay physically strong. We need to move faster now. AI is stepping in to replace our cognitive functions.

To counter this, we need weight training for the brain.

By all means, use AI responsibly. LLMs and AI-related tools are amazing. But exercise your brain too. Read more. Write more. Think for yourself first. In the age of artificial intelligence, the real advantage isn’t synthetic. It’s still deeply, stubbornly, brilliantly human.

Still reading?

Give this human brain a boost - like, share, or say hi. I’d love to know:

How are you keeping your originality alive in the age of AI?

Note 1: I haven’t read all 144 pages of the study, but I’ve reviewed the best available summaries and researcher commentary.

Note 2: The researchers advised against using words like “stupid” or “dumb.” I used them anyway. Because, frankly, the warning signs deserve strong words.