Examining the association between physical fitness, executive function, and memory

Abstract

As the aging population increases, neurodegenerative diseases present a growing threat. One such threat is Alzheimer’s disease, as it causes the deterioration of memory and the loss of independence. It is paramount to identify protective mechanisms that prevent or delay the onset of the disease. Physical activity may help to preserve aspects of cognitive function that decline with age and reduce the risk of Alzheimer’s disease. However, the underlying mechanism through which physical activity reduces the risk of Alzheimer’s disease is unknown. Although older adults who are more physically fit have better executive function, memory performance is unrelated to their physical fitness. This suggests that physical activity may not directly support memory to reduce the risk of Alzheimer’s disease. Instead, physical fitness may reduce the risk of Alzheimer’s disease by improving executive function, which may compensate for memory loss and artificially increase older adults’ beliefs about their memory ability. To examine the potential link between physical fitness, executive function and memory belief, we separated healthy older adults based on their score on the Montreal Cognitive Assessment (MoCA), a screening tool used to detect early signs of cognitive decline. As expected, older adults who passed the MoCA had better memory performance than those who failed. Furthermore, those who passed the MoCA had beliefs about their memory ability that mirrored their actual memory performance. However, the memory ability beliefs of those who failed the MoCA were unrelated to their actual memory performance; instead positive beliefs about their memory were related to better executive function performance and higher physical fitness. The results demonstrate the dissociation between the beliefs about memory ability and the actual memory ability of older adults with cognitive decline. The findings also reveal a novel association between physical fitness, executive function, and memory belief for individuals with cognitive impairment.