Testing-the-limits and the study of adult age differences in cognitive plasticity of a mnemonic skill.

Investigated the range and limits of cognitive reserve capacity as a general approach to the understanding of age differences in cognitive functioning.Testing-the-limits is proposed as a research strategy, Data are reported from 2 training studies involving old (65 to 83 years old) and young adults (19 to 29 years old).The training, designed to engineer an expertise in serial word recall, involved instruction and practice in the Method of Loci.Substantial plasticity was evident in pretest to posttest comparisons.Participants raised their serial word recall several times above that of pretest baseline.Age-differential limits in reserve capacity were evident in amount of training gain but not in responses to conditions of increased test difficulty (speeded stimulus presentation).Group differences were magnified by the training to such a degree that age distributions barely overlapped at posttests.Testing-the-limits offers promise in terms of understanding the extent and nature of cognitive plasticity.One of the perennial and unresolved questions of cognitive aging research is the distinction between performance and what has been variously labeled as competence, latent potential, or reserve capacity.Proposals for an empirical investigation of these concepts have focused on the study of the range and condi-