Slide Slam Q1
Leukoaraiosis and language later in life
Sara Sayers1, Roger Newman-Norlund1, Sarah Wilson1, Nicholas Riccardi1, Samaneh Nemati1, Sarah Newman-Norlund1, Julius Fridriksson1; 1University of South Carolina
Introduction: Leukoaraiosis, or the pathological appearance of white matter hyperintensities (WMHs) resulting from diseases of the small vessels, is thought to be a good indicator of overall brain health. Degeneration of deep and periventricular white matter tracts negatively affects structural connectivity between normally connected brain regions. Increased leukoaraiosis has been reported in dementia, cognitive decline, stroke, and aging. Our prior work in chronic post-stroke aphasia indicates that the extent of leukoaraiosis severity at initial evaluation is predictive of declines in language abilities at follow-up. The current study examined the relationship between leukoaraiosis and language (specifically discourse) in a healthy elderly population. Methods: Sixty participants (60-80 years old) completed the Montreal Cognitive Assessment (MoCA), produced narrative discourse and had MRI testing as a part of the Aging Brain Cohort testing battery at the UofSC. For the MoCA, the total score and six domain-specific index scores were calculated. White matter hyperintensities were manually identified and drawn by two independent, trained raters. WMH load (the percentage of white matter considered to be damaged) was calculated by normalizing the total WMH voxel count by overall brain size. To elicit a discourse sample for analysis, we administered Talkbank’s Cat Rescue picture description task. Trained study staff transcribed the video recordings, separated utterances into communication units, and coded the transcripts for specific linguistic variables using the CHAT transcription format for automatic analyses by the CLAN program. We focused our analysis on the relationship between WMH load and composite scores representing the fluency factor (maze index) and the semantic factor (percent noun, verbs, and pronoun index) scores, both previously associated with cognitive impairment. Results: Preliminary data indicated that WMH load was negatively correlated with the semantic factor (r (55) = -.285, p =.017, one-tailed) for the Cat Rescue discourse measure. The semantic factor was negatively correlated with age (r (59) = -.347, p=.003, one-tailed). There was no significant relationship between the fluency factor for the Cat Rescue and WMH load. When evaluating the relationship between WMH load and overall cognition, we found that WMH load was negatively correlated with the total MoCA score (r (55) = -.259, p=.027, one-tailed) which was primarily driven by a strong relationship between WMH load and executive functioning (r (55) = -.248, p=.033, one-tailed), visuospatial (r (55) = -.341, p=.005, one-tailed), and attention (r (55) = -.276, p=.020, one-tailed) skills. Accounting for age, the relationship for both the MoCA (r (52) = -.255, p=.030, one-tailed) and semantic factor (r (52) = -.242, p=.038, one-tailed) remained significant with WMH load. Discussion: Higher WMH load was associated with worse performance on the MoCA and less semantic content in spoken discourse measured by the semantic factor in older healthy adults. In light of corroborating research indicating an association between WMH load in the brain and greater risk for cognitive decline and dementia, the current study provides evidence that WMH load may predict language changes in normal aging and age-related mild cognitive impairment.