Brain rot began as internet slang for the mush of endless scrolling. It has since become something a board should take seriously: a measurable decline in the thinking of the people it pays most to think.
Brain rot began as internet slang for the mush of endless scrolling. It has since become something a board should take seriously: a measurable decline in the thinking of the people it pays most to think. The evidence is no longer anecdotal, and it points at the top of the house rather than the bottom.
In 2025, researchers at the MIT Media Lab fitted participants with EEG caps and asked them to write essays under different conditions. One group used ChatGPT, and the others worked with a search engine or with nothing but their own minds. The AI-assisted group showed the weakest neural connectivity across the regions responsible for planning and recall. The researchers named the residue cognitive debt, and found it lingered even after the AI was taken away (Kosmyna et al., 2025). Boston Consulting Group followed with survey data on nearly 1,500 employees describing acute mental fatigue among heavy AI users, a state workers have christened AI brain fry. Productivity gains reversed once people were managing more than three AI tools at once (Bedard et al., 2026).
Here is what the coverage keeps missing. The damage is sharpest at the top, because senior leaders are the people most rewarded for sounding fluent, and fluency is exactly what the machine hands out for free. A junior analyst who leans on AI produces work that gets checked. A chief executive who leans on it produces conviction that gets implemented.
My doctoral research across 6,000 executive leaders surfaced a pattern that should trouble every chair and every nomination committee. The more polished the AI-assisted output, the less able the executive was to defend the reasoning beneath it. I call this borrowed coherence. It reads as intelligence in the boardroom and performs beautifully in the investor call. It collapses under the first genuinely hard question, and by then the cost is reputational, which at senior level is rarely recoverable.
I watched this play out in an executive session I was running last year in London. A capable, Chief Strategy Officer presented a 2030 strategy that look polished, sounded immaculate, shared deep insights on the business, reflected the market position, cadenced and confident, but clearly produced by a model using detailed company information. I asked him a single question, a scenario based question we often use in future studies, and why this potential outcome, or what may be considered an option had been discarded. He could not answer it, because he had never formed the view. The room noticed. He had outsourced the thinking and kept only the performance of it, and the performance did not survive contact with scrutiny.
The wrong response is to ban the tools. Executives who refuse AI will simply be outpaced by executives who use it well. The right response is cognitive agency: the deliberate discipline of forming your own position before the model forms one for you. In my research, leaders who arrived at a problem with a written view and then used AI to attack that view sharpened over time. Leaders who prompted first and adopted whatever came back declined. The order of operations mattered more than the hours logged. Think first, then set the machine on your thinking as an adversary rather than an author.
This is not nostalgia for a pre-AI boardroom. It is a recognition that judgement, like any muscle, is built by load and lost by disuse, and that a leader who never lifts the weight will not have the strength when the moment demands it.
My recommendation is singular. Measure it. Cognitive decline at executive level stays invisible until it becomes expensive, which is why I built the Executive Cognitive Advantage Index. What a board cannot see, it cannot govern, and the most costly form of brain rot is the kind sitting at the head of the table.
For Board Advisory, Strategic Consulting, Keynote Speaking or Private Executive Advisory enquiries, please write with a short note on the decision, audience or transformation context. Suitable engagements are shaped through an initial private conversation.