Performance change while learning novel cognitive tasks as a potential identifier of preclinical Alzheimer's disease.

Background: In healthy older adults (OA), the effects of amyloid-β (Aβ) deposition on cognitive functions involved in learning are unclear. Objective: This study aimed to determine how age, practice, and neuropsychological test performance are associated with performance change during the learning of three cognitive tasks, and if Aβ deposition impacts performance change in OA. Methods: Fifty-five OA and 28 young adults completed neuropsychological tests, and Aβ deposition was assessed in OA. Participants learned three cognitive tasks: stop-go normal task (SGNT), stop-go reverse task (SGRT), and Results: In the basic model, more practice resulted in a larger performance change for SGNT and SGRT, but not NBT. In the second basic model, after two NBT practice trials, performance change increased with greater amounts of Aβ deposition and worse information processing speed but, after three practice trials, decreased with greater amounts of Aβ deposition and worse information processing speed. Across the three tasks, greater Aβ deposition tended (non-significant trend) to be associated with smaller improvements after more practice. Conclusions: These results suggest that the ability to learn a cognitive task is maintained with age but is negatively impacted by Aβ deposition.