Abstract Procrastination has immediately visible repercussions on health and survival resilience, yet shows stably heritable and remains increasingly pervasive across human societies. Despite a paradox, this behavior is theoretically explained to represent a byproduct of evolutionary advantages underlying impulsivity, yet not deciphered well by scientific evidences. After adjusting psychometric endogeneity, we demonstrate the unique predictive roles of non-planning impulsivity (NPI) during late adolescence and early adulthood uniquely predicts procrastination in later adulthood in a twin cohort ( N = 154). This association was further replicated in two independent cohorts ( N = 327, N = 1,543). Using AE models, in conjunction of single-paper meta-analytic synthesis ( N = 3,656 twin pairs), we observed significant shared genetic contributions underlying this NPI-procrastination association ( r g = 0.51, 95% CI : 0.18 - 0.84). Beyond to the phenotypic heritability, employing a Genome-Wide-Association Study (GWAS), six NPI-procrastination overlapping SNPs are identified, functionally accounting for neural dysregulation. Thus, leveraging neurodevelopmental normative modelling ( N = 37,407), online meta-analytic estimations ( k = 198, loci = 5,855) and seed-based d mapping estimates ( N = 893), cortical deviations in the left dorsolateral prefrontal cortex (DLPFC) - the brain region showing highest probabilistic overlap mapping NPI to procrastination, partly explains their shared genetic variants, but are substantially independent in genetic contribution. Mendelian Randomization analysis finally indicates causal roles of NPI and procrastination both, to DLPFC deviations. Our findings empirically clarified this theory that procrastination partly derives from NPI as an evolutionary byproduct indeed, but is still unique in neurogenetic entities. Brief summary Procrastination is a puzzling human behavior that compromises survival-relevant outcomes yet remains both widespread and heritable. Although theorized as a byproduct of impulsivity’s evolutionary advantages, empirical support for this account has been limited. Here, we provide converging evidence across psychometric, genetic, and neuroimaging modalities to show that non-planning impulsivity during late adolescence and early adulthood uniquely predicts later procrastination, and that the two traits share significant genetic overlap. We further identify specific genetic variants and morphological deviations in the DLPFC that link, but also partially dissociate, their biological pathways. These findings clarify the evolutionary and neurogenetic architecture of procrastination and underscore its partial derivation from impulsivity alongside distinct developmental origins.
Hu et al. (Tue,) studied this question.