There's been way too many papers. Here [1] is a link to Google Scholar for 'brain gut' which turns up a zillion results. Basically, your gut biome and brain are heavily linked. As a bonus, here's [2] a search for 'glyphosate gut microbiota.' Advances in biotech/consumables and dramatic unforeseen consequences seem completely inseparable.

[1] - https://scholar.google.com/scholar?hl=en&as_sdt=0%2C5&q=brai...

[2] - https://scholar.google.com/scholar?hl=en&as_sdt=0%2C5&q=glyp...