Polypoidal choroidal vasculopathy is not an uncommon disease in Italy and should be suspected in patients presenting with extramacular lesions and no large drusen in the fellow eye.

MEWDS may occur after MFC. Now that both directions of disease progression, MFC to MEWDS and MEWDS to MFC, have been well documented, it is likely that there is a common host susceptibility between these two distinct clinical diseases, if not a common pathogenesis.

Contextual events redundant to the learning, in sequence, of passive and active avoidance were of one type for the former task and of another for the latter. During later testing, these contextual events were found to determine which of these acquired, conflicting dispositions would be manifested in behavior. Mutual interference in retention otherwise seen under similar circumstances seemed subordinate to the influence of the three types of contextual stimuli tested-drug (pentobarbital), compound (the experimental room in which conditioning took place), and a relatively unitary stimulus (a constantly sounding buzzer). The discussion considered the defining characteristics of a "contextual stimulus" and the mechanisms through which contextual events control the manifestation of learned behaviors and alleviation of interference in retention.