A pre-registered test of competing theories to explain ego depletion effects using psychophysiological indicators of mental effort

Le résumé fourni par la source

A prominent, hotly debated idea—the ‘ego depletion’ phenomenon—suggests that engaging in effortful, demanding tasks leads to poorer subsequent self-control performance. Several theories seek to explain the emergence of ego depletion effects. The two most prominent ones are the strength model of self-control (Baumeister & Vohs, 2016) and the process model of self-control (Inzlicht & Schmeichel, 2012). Predictions of these models are predominantly identical on the behavioral level. The models’ predictions differ, however, on the level of invested mental effort. The present pre-registered study (N = 179) contrasted these competing predictions combining an established moderator counteracting ego depletion effects (i.e., self-affirmation) and psychophysiological indicators of mental effort (i.e., systolic blood pressure and pre-ejection period). Our data provide moderate evidence for ego-depletion—decrements in self-control performance after a high- versus low-demanding task in the non-affirmed conditions. Self-affirmation had an unexpected effect: Contrary to previous research, self-affirmed participants performed similarly poorly as participants in the high demand+non-affirmed condition. Although this unexpected finding limited the ability to contrast competing model predictions, it points to hitherto unknown effects of self-affirmation on self-control performance. Systolic blood pressure reactivity emerged as a valid indicator of invested mental effort, but the data show no sign of disengagement after a high demanding task predicted by the process (but not the strength) model. We explore systolic blood pressure progression across the sequential task paradigm, suggest a testable account for the effects of self-affirmation on self-control performance, and discuss theoretical implications of the results for the two competing models.

Ce résumé expose les affirmations des auteurs. BNTIC ne l’interprète pas comme une validation indépendante des résultats.