An autonomic reflection of syntactic structure

Subjects heard sentences in one ear during which a brief shock was administered before, in or after the division between two clauses. The galvanic skin response (GSR) to shocks objectively at the end of a clause was larger than the response to shocks at the beginning of a clause. This effect of syntax on GSR was larger for subjects who heard the speech in the right ear. An independent effect was that the GSR to shocks at the end of a clause decreased as a function of clause length; responses to shocks at the beginning of a clause were relatively unaffected by the length of the preceding clause in our stimulus materials.