Performance in the Iowa Gambling Task in healthy aging and mild cognitive impairment.

The Iowa Gambling Task is a common tool for assessing complex decision making in healthy adults and clinical populations. Previous work has found that performance varies among younger adults, cognitively healthy older adults, and individuals with mild cognitive impairment (MCI), a syndrome often precedes dementia. However, performance on the task depends on many factors, including risk preference, sensitivity to gains and losses, and memory for past outcomes, which makes it difficult to understand what causes these differences. Here, we fit a computational cognitive model to the data which allows us to attribute differences in behavior to specific cognitive mechanisms. Experiment 1 (N = 90) compares cognitively healthy older adults to those with MCI, while Experiment 2 (N = 1,645) compares healthy adults of all ages. We find that healthy older adults and those with MCI exhibit different profiles in the task. Healthy aging is associated with a larger learning rates (we attribute to a recency bias), use of a perseverative strategy, and increased sensitivity to gains over losses. Individuals with MCI learned at a slower rate, but showed no qualitative differences in task strategy. The results have implications for understanding why decision making is impaired in the earliest clinical phases of cognitive decline. (PsycInfo Database Record (c) 2025 APA, all rights reserved).