Sentence:  Thus cortico-fugal discharges induced by topical application of <WSD>strychnine</WSD> to a minute area in the neocortex summate with spikes present in the hypothalamus and cause increased convulsive discharges . 
Meaning of the word marked with <WSD> tags:  an alkaloid plant toxin extracted chiefly from nux vomica; formerly used as a stimulant