Aging and Cognition

This article provides an overview of cognitive aging research with focus on normal aging. Results from longitudinal studies have revealed that cognitive abilities are more stable than early findings from cross-sectional studies indicated. It is also clear that crystallized abilities, such as knowledge, vocabulary, and verbal abilities are mostly stable or even may show an improvement across the adult life-span, whereas fluid abilities such as speed, executive function, working memory, and episodic memory are negatively affected in aging. Although fluid cognitive abilities tend to decline with age crystallized abilities can provide cognitive support and in this respect compensate deficits in everyday problem solving. Much research has been conducted in the last decades to identify factors that contribute to cognitive aging. It is well established that genetic, health-related (e.g., hypertension, diabetes, homocysteine, and vitamin status), as well as lifestyle factors (e.g., education, substance use, physical- and social activities) are of importance for cognitive functioning. Some of the age-related variations in cognitive performance is also mediated by changes in other cognitive processes such as speed. There is, however, still age-related variation that has not been accounted for which emphasize the need for further research and suggest that multiple aging processes affect our central nervous system and thereby various mechanisms involved in cognitive functioning.