Devaluation of NoGo stimuli is both robust and fragile.

Consistently not responding to stimuli during go/no-go training leads to lower evaluations of these NoGo stimuli. How this NoGo-devaluation-effect can be explained has remained unclear. Here, we ran three experiments to test the hypothesis that people form stimulus-stop-associations during the training, which predict the strength of the devaluation-effect. In Experiment 1, we tried to simultaneously measure the stimulus-stop-associations and NoGo-devaluation, but we failed to find these effects. In Experiment 2, we measured NoGo-devaluation with established procedures from previous work, and stimulus-stop-associations with a novel separate task. Results revealed a clear NoGo-devaluation-effect, which remained visible across multiple rating blocks. Interestingly, this devaluation-effect disappeared when stimulus-stop-associations were measured before stimulus evaluations, and there was no evidence supporting the formation of the stimulus-stop-associations. In Experiment 3, we found evidence for the acquisition of stimulus-stop-associations using an established task from previous work, but this time we found no subsequent NoGo-devaluation-effect. The present research suggests that the NoGo-devaluation-effect and stimulus-stop-associations can be found with standard established procedures, but that these effects are very sensitive to alterations of the experimental protocol. Furthermore, we failed to find evidence for both effects within the same experimental protocol, which has important theoretical and applied implications.

Confidence in evaluations and value-based decisions reflects variation in experienced values.

Evaluations and value-based decisions are often accompanied by a feeling of confidence about whether or not the evaluation or decision is accurate. We argue that this feeling of confidence reflects the variation of an underlying value distribution and that this value distribution represents previously experienced values related to an object. Two preregistered experiments in which the variation of such value distributions was systematically varied provide causal evidence in favor of this hypothesis. A third preregistered experiment showed that, for natural food items with uncontrolled prior experiences, confidence in evaluations is again related to the variation of individuals' self-reported value distributions. Similarly, for choices between items, the variation of experienced values related to a choice pair influenced confidence in the perceived correctness of the choice. These findings converge with other domains of decision making showing that confidence tracks the variation of the underlying probability distribution of the evidence that a decision is based on, which in the case of value-based decisions, is informed by a value distribution reflecting priorly experienced values. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

The role of attention in explaining the no-go devaluation effect: Effects on appetitive food items.

Evaluations of stimuli can be changed by simple motor responses such that stimuli to which responses are consistently withheld tend to be evaluated less positively than other stimuli. The exact mechanism that underlies this no-go devaluation effect is still unknown. Here we examine whether attention to the stimuli during training contributes to the devaluation effect. Participants received a go/no-go training in which 2 go items or 2 no-go items were simultaneously presented, and attention to 1 of the items was cued before participants executed or withheld a simple motor response (press a key on a keyboard). Next, explicit evaluations of these stimuli and untrained stimuli were assessed. Across 2 experiments we observed a predicted no-go devaluation effect, that is, a decrease in evaluations for items that have not been responded to. Furthermore, as predicted, selectively cueing attention toward stimuli during go/no-go training amplified differences in subsequent evaluations between go and no-go stimuli. Confirmatory analyses showed that the devaluation effect for cued no-go stimuli was not statistically significantly stronger than that for uncued no-go stimuli within each experiment. However, combining the data of both experiments showed moderate evidence (p = .023, BF+0 = 5.88) for stronger devaluation of cued no-go stimuli compared with uncued no-go stimuli. We conclude that attention to stimuli during go/no-go training contributes to revaluation processes of stimuli via motor actions, and that this knowledge is relevant for a better understanding of the underlying mechanism of the training and to optimize go/no-go training for practical use. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

When mere action versus inaction leads to robust preference change.

Understanding the formation and modification of preferences is important for explaining human behavior across many domains. Here we examined when and how preferences for food items can be changed by linking mere action versus inaction to these items. In 7 preregistered experiments, participants were trained to consistently respond to certain food items (go items) and not respond to other items (no-go items) in a go/no-go training. Next, to assess preferences, they repeatedly chose between go and no-go items for consumption. Decision time during the choice task was manipulated and measured. Immediately after training, participants chose go items more often for consumption when choosing under time pressure, for both high-value and low-value choice pairs. Preferences were reliably changed in favor of go items for choices between unhealthy foods, between healthy foods, and between healthy and unhealthy foods. Furthermore, preference change was still observed one week after training, although the effect size largely decreased. Interestingly, when participants made choices without time pressure, the effect became weaker and statistically nonsignificant. These results suggest that preference change induced by mere responding versus not responding is constrained to situations where people take little time to make decisions, and the effect is relatively short-lived. By showing the reliability, generalizability and boundary conditions of the effect, these findings advance our understanding of the underlying mechanisms of go/no-go training, provide more insights into how the training can be effectively applied, and raise new theoretical questions on how mere action versus inaction impacts preferences. (PsycINFO Database Record (c) 2019 APA, all rights reserved).