Motivational effects on brain activity: need for closure moderates the impact of task uncertainty on engagement-related P3b.

Abstract

Need for cognitive closure (NFC), that is, individual's aversion toward uncertainty and the desire to reduce it quickly usually manifests in effort minimizing cognitive strategies. Recent studies, however, demonstrated that it is also linked with laborious processing when the task itself induces uncertainty. Although this pattern was observed when testing behaviors and cardiovascular activity, it has never been tested on a neurocognitive level. To fill this gap, we investigate whether NFC moderates the impact of task uncertainty on engagement-related P3b component of brain activity. In the experiment, we recorded the electroencephalographic activity of the brain while participants performed a sampling task which provides uncertainty manipulation within participants. We also manipulated NFC between participants. As predicted, we did not find any differences between high and low NFC participants in the P3b component at lower levels of uncertainty. However, at the highest level of uncertainty, the P3b component decreases significantly among low but not high NFC participants. That is because gaining certainty and achieving closure is not a critical epistemic goal for low NFC and thus, exerting extra effort to gain certainty is not justified.