Sentence:  A state of parasympathetic `` tuning '' of the hypothalamus induced experimentally causes not only an increase in the parasympathetic reactivity this structure to direct and reflexly induced stimuli , but leads also to an autonomic reversal : a stimulus acting sympathetically under control conditions elicits in this state of tuning a parasympathetic <WSD>response</WSD> ! 
Meaning of the word marked with <WSD> tags:  a bodily process occurring due to the effect of some antecedent stimulus or agent