[O3–01–02]: TIMECOURSE OF BRAIN AND COGNITIVE CHANGES FOLLOWING TWO TYPES OF ATTENTIONAL TRAINING PROGRAMS: A THREE‐TIME POINTS FMRI INTERVENTION STUDY IN OLDER ADULTS

Background:Occupational cognitive complexity may reduce risk for cognitive decline in aging. How it affects brain structure and whether it exerts influence in mid-life is unclear. We investigated whether occupational cognitive complexity in early to mid-adulthood is associated with brain structure and cognitive health in mid-life. Methods: Participants were 669 adults from the Coronary Artery Risk Development in Young Adults (CARDIA) cohort study (ages 18-30 at baseline, 52% female, 38% black). As our measure of occupational cognitive complexity, we calculated Occupational Cognitive Requirements scores (OCRS) using participants’ Census Occupation Codes (Years 10 and 15) and Occupational Information Network (O*Net) data; OCRS reflect the cognitive complexity of participants’ most demanding occupation. At Year 25, participants had structural brain MRI, diffusion tensor imaging, and cognitive testing [Digit Symbol Substitution Test (DSST), Stroop, and Rey Auditory Verbal Learning Test (RAVLT)]. In adjusted mixed models, we examined associations between OCRS in early to midadulthoodwith graymatter volume andwhitematter fractional anisotropy (FA) by lobe and cognition inmid-life.Adjustedmodels included demographics, education, hypertension, diabetes, depressive symptoms, and smoking. Results: Higher OCRS was associated with greater white matter FA, especially in frontal (Estimate 1⁄4 0.0019, p 1⁄4 0.03) and temporal (Estimate 1⁄4 0.0030, p 1⁄4 0.001) lobes, but not gray matter volumes. Higher OCRS was associated with better DSST (Estimate 1⁄4 .13, p < 0.001) and Stroop (Estimate 1⁄4 0.09, p1⁄4 0.01) performance, but not RAVLT performance. Conclusions:Occupational cognitive complexity in early to mid-adulthood is associated with better white matter integrity (FA) and cognitive function in mid-life, possibly promoting cognitive reserve. Whether and how these associations help protect the aging brain into late life remains to be determined.