The impact of age in rule-based and information-integration category learning tasks

The ability to acquire new skills is essential throughout the lifespan and allows older adults to maintain independence and quality of life. Age-related declines in learning may stem from impairments in declarative systems supporting rule-based (RB) reasoning, procedural systems supporting associative learning, or their interaction. Prior work has yielded mixed findings regarding which of these specific processes (simple rules, complex rules, or procedural acquisition) is disproportionately affected by aging. Category learning provides a useful paradigm to disentangle these possibilities, as it distinguishes between RB tasks supported by the declarative system and information-integration (II) tasks driven by the procedural system. The present study compared younger (n = 53; aged 17-49 years) and older (n = 30; aged 60-79 years) adults on a one-dimensional (1RB), a two-dimensional (2RB), and an II category learning task. Bayesian survival analyses revealed that older adults reached criterion at approximately 57% of the rate of younger adults in the 1RB task, 78% in the 2RB task, and 75% in the II task. Thus, age-related slowing was greatest in the simplest RB condition and weaker in the more complex 2RB and II tasks. The 1RB effect was also estimated with greater clarity, whereas the 2RB and II effects were directionally similar but more uncertain. These effects may reflect impairments in either or both learning systems or difficulty shifting between them. (PsycInfo Database Record (c) 2026 APA, all rights reserved).