EEG revealed significant differences in brain connectivity: Brain-only participants exhibited the strongest, most distributed networks; Search Engine users showed moderate engagement; and LLM users displayed the weakest connectivity. Cognitive activity scaled down in relation to external tool use.
Over four months, LLM users consistently underperformed at neural, linguistic, and behavioral levels.
No it’s more complex than that. In the final session, participants were swapped between the LLM and Brain groups, and the effects persisted to some extent.
So it’s worse than “using an LLM doesn’t engage your brain”, it’s more like “using an LLM actually makes you dumber.”