Problems with current hypotheses of catecholamine involvement in antidepressant action are reviewed. The theories examined include those that attribute a key role to increased brain norepinephrine (NE) availability or to the desensitization of brain beta adrenergic receptors. Although these hypotheses are consistent with a great deal of relevant laboratory and clinical data there arc an increasing number of findings that cannot be explained by them. These contradictions include findings on the lag time between pharmacological and therapeutic effects of antidepressants, the actions of propranolol and thyroid hormones on depression, the relationship between cortisol secretion and depression, the net effect of chronic antidepressants on noradrenergic neurotransmission, and the functions of cyclic AMP in the CNS. To reconcile the discordant data in these areas of research, a new formulation, the output hypothesis, which is derived from the foregoing theories, is proposed. The new hypothesis assumes that depression or adverse behavioral effects of stress results when the output of brain cells bearing noradrenergic receptors is too low to meet increased demand resulting from stress or other biologically disruptive events. According to this view antidepressants act by a mechanism akin to adaptation to chronic stress in which there is a prolonged increase in postsynaptic noradrenergic receptor activation in the brain. The prolonged increase is necessary for NE to induce, via the beta adrenoceptor–cAMP system, trophic or long-term metabolic effects that increase the output of catecholamine effector cells to a level commensurate with demand.

Story grammars have been proposed as a means of expressing a theory of stories. Story grammarians claim that stories are a linguistic form in much the same sense that sentences are, and that we can attribute constituent structure to stories in much the same way we attribute it to sentences. Just as sentences and their constituent structure can be characterized by sentence grammars, so stories and their constituent structure can be characterized by a story grammar. However, the analogy between story grammars and sentence grammars is ill conceived. It is based on a category error that assumes stories to be textual entities like sentences. This is demonstrably not the case. Moreover, this confusion is the cause of most of the misunderstandings about story grammars and what they can accomplish. Once this mistake is acknowledged, the possible contribution of story grammars to a theory of stories is considerably diminished. In place of story grammars, I propose the rudiments of a theory, called the theory of story points. Although it lacks some of the aesthetic appeal of story grammars, the theory of story points seems a more promising route to a meaningful theory of stories. The theory is being used as a component of a computer story-understanding system under development at Berkeley. In addition, some very preliminary experiments conducted on the basis of this approach seem to lend it some psychological plausibility.