Memory encoding and aging: a neurocognitive perspective.

This review article surveys the evidence for age-related changes in memory from cognitive and neuroimaging studies. It is probable that the observed declines in episodic memory with increasing age are a consequence of impairments in both acquisition (encoding) and retrieval - possibly for similar reasons - but the present review focuses on the former set of processes. An additional emphasis is on a processing approach to understanding age-related encoding deficiencies; we suggest that many problems stem from a decline in the ability to self-initiate deeper semantic processing operations. The article briefly discusses the role of declining sensory and perceptual abilities, but focuses primarily on the nature of processing resources, their consequences for memory acquisition, and on age-related changes in cognition and neural functioning. We also survey the evidence for neuroplasticity in the older brain, and how compensatory activities at behavioral and neural levels can reduce age-related problems. Finally, we review recent studies of brain and cognitive training procedures. Age-related memory problems are real, but there are also grounds for optimism.