Developing context and background underlying cognitive intervention/training studies in older populations.

Underlying the attempt to change behavior or improve performance by virtue of intervention or training is the notion that change is possible and that plasticity, life-course malleability, and compensation are well-recognized concepts of life-span development. The cognition and aging literature reveals that there are a growing number of context and background variables against which the effectiveness of intervention/training can be judged beyond the intrinsic motivations for change. In this introductory article to a special issue on cognitive intervention and training, we briefly discuss several of these background variables.