Basil Bernstein's 1973 studies comparing English and math comprehension differences in class. Halliday's Language and Society Vol 10 Primate Psychology Mastripietri Apes and Evolution Tuttle Symbolic Species Deacon Origin of Speech MacNeilage

That's the tip of the iceberg

edit: As CS doesn't understand the parasitic or viral aspects of language and simply idealizes it, it can't access it. It's more of a black box than the coding of these. I can't understand how CS assumed this would ever work. It makes no sense to exclude the very thing that language is and then automate it.