https://www.technocracy.news/new-study-from-mit-chatgpts-impact-on-our-brains/

The group that wrote essays using ChatGPT all delivered extremely similar essays that lacked original thought, relying on the same expressions and ideas. Two English teachers who assessed the essays called them largely “soulless.” The EEGs revealed low executive control and attentional engagement. And by their third essay, many of the writers simply gave the prompt to ChatGPT and had it do almost all of the work. “It was more like, ‘just give me the essay, refine this sentence, edit it, and I’m done,’” Kosmyna says. The brain-only group, conversely, showed the highest neural connectivity, especially in alpha, theta and delta bands, which are associated with creativity ideation, memory load, and semantic processing. Researchers found this group was more engaged and curious,and claimed ownership and expressed higher satisfaction with their essays.”