Associations Between Vestibular Perception and Cognitive Performance in Healthy Adults.

Objectives: A growing body of evidence has linked vestibular function to the higher-order cognitive ability in aging individuals. Past evidence has suggested unique links between vestibular function and cognition on the basis of end-organ involvement (i.e., otoliths versus canals). However, past studies have only assessed vestibular reflexes despite the diversity of vestibular pathways. Thus, this exploratory study aimed to assess associations between vestibular perception and cognition in aging adults to determine potential relationships.

Design: Fifty adults (21 to 84 years; mean = 52.9, SD = 19.8) were included in this cross-sectional study. All participants completed a vestibular perceptual threshold test battery designed to target perception predominantly mediated by each end-organ pair and intra-vestibular integration: 1 Hz y-translation (utricle), 1 Hz z-translation (saccule), 2 Hz yaw rotation (horizontal canals), 2 Hz right anterior, left posterior (RALP), and left anterior, right posterior (LARP) tilts (vertical canals), and 0.5 Hz roll tilt (canal-otolith integration). Participants also completed standard assessments of cognition and path integration: Digit Symbol Substitution Test (DSST), Trail Making Test (TMT), and the Gait Disorientation Test (GDT). Associations were assessed using Spearman rank correlation, and multivariable regression analyses.

Results: For correlation analyses, DSST correlated to RALP/LARP tilt, roll tilt, and z-translation. TMT-A only correlated to z-translation, and TMT-B correlated to roll tilt and z-translation after correcting for multiple comparisons. GDT correlated to RALP/LARP tilt and y-translation. In age-adjusted regression analyses, DSST and TMT-B were associated with z-translation thresholds and GDT was associated with y-translation thresholds.

Conclusions: In this cross-sectional study, we identified associations between vestibular perceptual thresholds with otolith contributions and standard measures of cognition. These results are in line with past results suggesting unique associations between otolith function and cognitive performance.