Memory and aging: components and processes

This article provides a critical review of memory and aging. The focus is on the more accepted ternary scheme of memory, i.e. procedural, semantic and episodic, and on processing resources. A review of the literature in these areas, considering the more relevant studies or those with a greater number of subjects, reveals a gradual decrease of performance with age. No single hypothesis, either psychological or physiological, seems to be capable of explaining this decline. However, the hypothesis of a cognitive slowing during aging has an appealing simplicity and offers the chance to integrate the myriad of task-specific explanations that have proliferated in the literature.