Does it all go together when it goes? The Nineteenth Bartlett Memorial Lecture

Area of Science:

• Psychology
• Neuroscience
• Gerontology

Background:

• Cognitive abilities show increasing differences between individuals as they age.
• Within-individual cognitive performance variability also increases with age.

Purpose of the Study:

• To explore the implications of increasing between- and within-individual cognitive variance during aging.
• To question the fluid-crystallized distinction and its role in cognitive aging.
• To evaluate models of age-related cognitive decline.

Main Methods:

• Analysis of large-scale cross-sectional studies.
• Examination of cognitive performance data including IQ tests, information-processing tasks, and memory tasks.

Main Results:

• Age-related cognitive aging exhibits increasing between-individual differences.
• Within-individual cognitive performance shows greater variability.
• Evidence suggests disparate rates of decline across various "fluid" cognitive abilities.
• Cognitive skills do not decline uniformly; characteristic patterns of aging emerge.

Conclusions:

• The distinction between "fluid" and "crystallized" abilities may not fully capture the complexity of cognitive aging.
• Age-related cognitive decline is characterized by specific patterns or syndromes, not a single factor.
• Understanding these patterns is crucial for addressing cognitive aging.