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http://dx.doi.org/10.1037/11246-016
Some individuals, instead of manifesting a consistent type of reaction tendency, adopt at different times what appear to be inconsistent reactions. These episodic reactions we shall discuss in this chapter. The most striking of these are the manic depressive cycles, and the catatonic excitement and stupor. A study of the personality behind these reactions will make them appear less inconsistent than their superficial observation suggests. (PsycINFO Database Record (c) 2016 APA, all rights reserved)