Housing Warmth/Coolness and Quietness Correlate With Whole‐Brain Fractional Anisotropy in Healthy Adults

Introduction Residential environments have been linked to brain structure, particularly in children, older adults, and clinical populations. However, little is known about how different dimensions of the housing environment relate to brain white matter microstructure in healthy adults, or whether specific environmental factors show stronger associations than others. Methods In this cross‐sectional study, we examined the associations between six self‐reported housing environment domains—warmth/coolness, quietness, brightness, cleanliness, safety, and security—assessed using the Housing Health Checklist, and whole‐brain fractional anisotropy (FA) in 278 healthy adults. Whole‐brain FA was quantified using both the arithmetic mean of regional FA values and a principal component–based summary measure. Hierarchical multiple regression analyses were conducted while controlling for demographic factors, physiological measures, outdoor temperature, pollution indicators, total housing environment score, gray matter brain healthcare quotient, and site‐related effects. Results After covariate adjustment, warmth/coolness and quietness were modestly but significantly associated with whole‐brain FA, whereas brightness, cleanliness, safety, and security were not. These associations were consistent across both FA summary measures. The incremental variance explained by housing environment variables was small. Conclusion The findings indicate that perceived warmth/coolness and quietness are selectively associated with variability in whole‐brain white matter microstructure in healthy adults. While the observed effect sizes were modest and the cross‐sectional design precludes causal inference, the results highlight specific dimensions of the residential environment that may warrant further investigation in longitudinal and interventional studies.