Bidirectional Financial Exchange and Late-Life Depression: Beyond Net Resource Flows to Exchange Structure

Existing literature frames intergenerational transfers as resource buffering. This study, adopting a family obligation perspective, examined whether contemporaneous bidirectional exchange predicts elevated depressive symptoms net of directional transfer intensity, and extended "bidirectionality" from a binary indicator to a multidimensional structural attribute. Using CHARLS panel data, we found that higher directional transfer intensity was associated with fewer depressive symptoms, whereas bidirectional co-occurrence was positively associated with depressive symptoms and persisted in lagged models. Multidimensional operationalization further showed that this positive association held independent of total intensity: entering a bidirectional structure was linked to more severe symptoms, potentially reflecting the psychological costs of simultaneously occupying "supporter" and "dependent" roles, while the synergistic interaction between received and provided intensities exhibited a mitigating effect. These findings clarify that the existence, structural entry, and synergy of bidirectional exchange constitute separable effect dimensions.