Path integration in healthy older adults and population with subjective cognitive decline
Mon-B21-Talk I-04
Presented by: Vladislava Segen
Path integration deficits are apparent in healthy older adults and Alzheimer’s disease (AD) patients. Yet, it remains unclear which specific aspects of the path integration process are most affected and whether these processes are differentially affected in older adults and those with AD. Here, we used immersive virtual reality to characterise path integration deficits in healthy older adults and those with subjective cognitive decline (SCD). During the task participants had access to multisensory self-motion cues (visual, vestibular and proprioceptive) as they were immersed in an open-field virtual environment and guided along short, curved paths. At certain points participants were asked to stop and indicate their initial heading orientation and start location. Overall, we found impaired path integration performance in the SCD group. These differences were not explained by general cognitive status, visuospatial working memory, subjective spatial abilities as well as balance. To further characterise the sources of the observed errors we used a computational model that allows us to decompose different parameters that contribute to the observed path and angular integration errors. Preliminary analysis suggests that memory leak, and randomly accumulating noise (across distance) is larger in the SCD group. Accumulating noise was also a key parameter in predicting path integration error in both groups, however, its contribution was larger in healthy older adults. These results will be discussed with reference to different mechanisms contributing to path integration deficits in healthy older adults and those with SCD.
Keywords: Navigation, Aging, Alzheimer Disease, Spatial cognition