Directional Asymmetry Without Timescale Dependence: Longitudinal Associations Between Procrastination and Depressive Symptoms.

Background: Longitudinal research has examined procrastination-emotion dynamics across diverse temporal intervals, yet it remains unclear whether findings obtained at different timescales reflect distinct underlying mechanisms. Guided by an emotion-regulation account, the present study tested the hypotheses that negative emotions predicted subsequent procrastination more strongly at shorter intervals, whereas procrastination predicted increases in depressive symptoms over longer intervals. Methods: To test whether the procrastination-depressive symptoms coupling varied across temporal scales, we integrated three longitudinal datasets (i.e., daily, 1-month, and half-yearly intervals) and compared models in which within-person lagged effects (i.e., from depressive symptoms to procrastination and the reverse path) were allowed to vary versus constrained to be invariant across timescales. Directional paths were then reported based on the better-fitting model. Results: Model comparisons favored the timescale-invariant model over the timescale-variant model for both directional paths. Across multiple temporal scales, the timescale-invariant model showed negligible effects of depressive symptoms on subsequent procrastination, while procrastination predicted increases in depressive symptoms. Conclusion: Contrary to timescale-dependent expectations, no evidence for temporally distinct mechanisms was observed within the examined intervals. Instead, the findings reveal a modest directional asymmetry across timescales, suggesting that procrastination may have consistent but small effects on subsequent increases in depressive symptoms rather than forming a reciprocal feedback loop.