Multisensory, Multi-Tasking Performance of Older Adults With and Without Subjective Cognitive Decline

As the population ages, it is increasingly important to detect non-normative cognitive declines as early as possible. Measures of combined sensory-motor-cognitive functioning may be early markers for identifying individuals who are at increased risk of developing dementia. Further, older adults experiencing subjective cognitive decline (SCD) may have elevated risk of dementia compared to those without SCD. Tasks involving complex, multisensory interactions reflective of everyday challenges may be particularly sensitive to subjectively perceived, pre-clinical declines. In the current study, older adults with and without SCD were asked to simultaneously perform a standing balance task and a listening task under increasingly challenging sensory/cognitive/motor conditions using a dual-task paradigm in a realistic, immersive virtual environment. It was hypothesized that, compared to older adults without SCD, those with SCD would exhibit greater decrements in postural control and listening response accuracy as sensory/motor/cognitive loads increased. However, counter to predictions, older adults with SCD demonstrated greater reductions in postural sway under more challenging dual-task conditions than those without SCD. Across both groups, poorer postural task performance was associated with poorer cognitive function and speech-in-noise thresholds measured with standard baseline tests. Poorer listening task performance was associated with poorer global cognitive function, poorer mobility, and poorer speech-in-noise detection. Overall, the results provide additional support for the growing evidence demonstrating associations between sensory, motor, and cognitive functioning and contribute to an evolving consideration of how best to categorize and characterize SCD in a way that guides strategies for screening, assessment, and intervention.