Sentence:  Important as these differences are , they should not obscure the basic fact that by shifting the hypothalamic balance sufficiently to the parasympathetic side , we produce depressions , whereas a shift in the opposite direction causes <WSD>excitatory</WSD> effects and , eventually , maniclike changes . 
Meaning of the word marked with <WSD> tags:  (of drugs e.g.) able to excite or stimulate