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 <WSD>depressions</WSD> , whereas a shift in the opposite direction causes excitatory effects and , eventually , maniclike changes . 
Meaning of the word marked with <WSD> tags:  a mental state characterized by a pessimistic sense of inadequacy and a despondent lack of activity