Social desirability bias obscures mind-wandering reports

The study of mind-wandering relies on the assumption that people accurately introspect and report on their attentional state. Yet self-reports may be distorted by extraneous motives, such as a desire to appear attentive. Across two sustained attention tasks, we demonstrate that social desirability bias is systematically linked with task-unrelated thought (TUT). In Experiment 1, higher social desirability bias scores predicted fewer subjective TUT reports during a reaction time task, despite no relationship with objective response times (RTs). This suggests a self-presentation effect rather than true attentional differences. Time pressure during thought probes further weakened RT–TUT coupling. In Experiment 2, controlling for social desirability bias enhanced the ability of an objective, RT-based real-time triggering procedure to predict deeper subjective TUT reports in the Sustained Attention to Response Task (SART). The alignment between objective triggers and subjective reports was strong for low-bias individuals, but weakened for those high in bias. Triggers were also less effective at capturing working memory lapses in participants prone to deliberate mind-wandering, suggesting that intentional off-task thinking manifests differently in behavior. The results show that social desirability bias can obscure TUT reports and should be considered in a science of attention and thought.