Aside from some of the symposia which have been published, very few books have dealt strictly with the concept of emotion. The task of unifying the numerous, frequently inconsistent findings has at last been accomplished by Gellhorn and Loofbourrow, within the general framework of Gellhorn's theoretical notions.
While there is an attempt to cover a broad range of phenomena under the topic of emotion, the physiological basis of emotional behavior is stressed. In particular, the authors emphasize the importance of the hypothalamus and its unique role in relation to the rest of the nervous system. Emotion derives from the activities of the hypothalamic-limbic system, together with the reticular formation and neocortex. The expression of emotion can occur in the absence of the neocortex, but feeling necessitates the neocortex and is defined as the "subjective interpretation of inner states."
The book begins with a discussion of the principles of nervous integration,