Key Takeaways
- Over half of Americans use AI, according to a 2025 YouGov survey.
- Using the technology too much can lead to a new problem called “brain fry,” which Harvard Business Review recently defined as “mental fatigue.”
- Survey respondents described a buzzing or foggy feeling, headaches and slower decision‑making.
Using AI too much can lead to a new problem called “AI brain fry,” according to a new Harvard Business Review study. The issue arises when AI users push their minds to exhaustion.
The study defined brain fry as “mental fatigue from excessive use or oversight of AI tools beyond one’s cognitive capacity.” It shows up when workers are constantly prompting models, reviewing outputs, switching between tools and monitoring AI systems at a pace their brains can’t comfortably sustain.
In Harvard Business Review’s survey of 1,488 full‑time U.S. workers, 14% of those using AI said they had experienced this kind of mental fatigue. Respondents described a buzzing or foggy feeling, headaches, slower decision‑making and a sense that they couldn’t tell whether their AI‑assisted work “made any sense” anymore.
These effects were especially common in roles like marketing, software development, human resources and finance, where people juggle multiple AI tools and information streams at once.
Brain fry is different from classic burnout, which stems from a chronically heavy workload, lack of control and emotional exhaustion over time. Instead, brain fry is about acute cognitive overload, like having too many browser tabs open in your head. The study linked AI brain fry to concrete performance and retention risks, including higher error rates, greater information overload and a higher intention to quit.
How to avoid AI brain fry
AI is increasingly becoming more popular. Over half of Americans (56%) use it, according to a 2025 YouGov survey.
The Harvard Business Review study indicated that using AI to offload repetitive, low-value tasks instead of multiplying oversight duties can actually reduce burnout. Workers who only used AI to automate routine work saw lower burnout scores because their mental energy shifted to more meaningful tasks.
At an individual level, the research showed that people can prevent brain fry by limiting the number of AI tools they use at once, avoiding constant task-switching, and scheduling regular breaks.
At a team or organizational level, the research suggested that managers should be intentional about when and how they require AI. The study emphasized integrating AI where it reliably cuts back busy work, like document summaries, basic coding and first drafts.
“The AI can run out far ahead of us, but we’re still here with the same brain we had yesterday,” Julie Bedard, managing director and partner at Boston Consulting Group and an author of the study, told CBS News. “We need to redesign how we do our work… where we don’t just keep exactly what we did yesterday and put AI on top of it.”
Key Takeaways
- Over half of Americans use AI, according to a 2025 YouGov survey.
- Using the technology too much can lead to a new problem called “brain fry,” which Harvard Business Review recently defined as “mental fatigue.”
- Survey respondents described a buzzing or foggy feeling, headaches and slower decision‑making.
Using AI too much can lead to a new problem called “AI brain fry,” according to a new Harvard Business Review study. The issue arises when AI users push their minds to exhaustion.
The study defined brain fry as “mental fatigue from excessive use or oversight of AI tools beyond one’s cognitive capacity.” It shows up when workers are constantly prompting models, reviewing outputs, switching between tools and monitoring AI systems at a pace their brains can’t comfortably sustain.
