Abstract: | Partial blockade of beta-adrenergic end-organ response to the autonomic nervous system was effected in a group of older men by administration of propranolol. The result was improved performance in a learning task. The data support the hypothesis that the learning decrement found among older men is not simply a manifestation of structural change in the central nervous system but is, at least in part, associated with the heightened arousal of the autonomic nervous system that accompanies the learning task. |