White matter fibers mediate the relationship between workload, resource use, and burnout: a new attempt to apply the conservation of resources theory to neuroscience.

As global competition intensifies, work-related stress and burnout have become increasingly prevalent, yet their neural correlates remain poorly understood. Drawing on the Conservation of Resources (COR) theory as a conceptual framework, this study examined whether white-matter integrity in executive-function-related brain tracts statistically mediates the associations between workload, resource use, and burnout. Using cross-sectional diffusion MRI data from 188 healthy adults in Japan, we focused on fractional anisotropy (FA) in the superior longitudinal fasciculus (SLF), internal capsule (IC), and external capsule (EC), which have been consistently linked to executive functioning. Correlation and mediation analyses revealed that higher workload was negatively associated with FA in the SLF, IC, and EC, whereas FA in these tracts was negatively associated with cynicism, a core dimension of burnout. Resource use was positively associated with FA in the SLF. Mediation analyses further indicated that FA in the SLF, IC, and EC partially mediated the association between workload and cynicism, and that FA in the SLF fully mediated the association between resource use and cynicism. No comparable mediation effects were observed for exhaustion or professional efficacy. These findings should be interpreted as associative rather than causal. FA is not conceptualized as a resource itself, but as a neural correlate of executive-function capacity that covaries with psychological resource dynamics. By integrating a well-established stress-behavior framework with structural neuroimaging, this study provides an initial interdisciplinary perspective on how work-related demands, resource utilization, and burnout-related attitudes align with individual differences in white-matter integrity.