Preparing for (valenced) action: The role of differential effort in the orthogonalized go/no-go task.

Associating reward to task performance has been shown to benefit scores of cognitive functions. Importantly, this typically entails associating reward to the execution of a response, hence intertwining action-related processes with motivational ones. However, recently, preparatory action requirements (go/no-go) and outcome valence (reward/punishment) were elegantly separated using a cued orthogonalized go/no-go task. Functional magnetic resonance imaging results from this task showed that typical areas of the "reward network," like the dopaminergic midbrain and the striatum, predominantly encode action rather than valence, displaying enhanced activity when preparing for action (go) compared to inaction (no-go). In the current study, we used ERPs to probe for differences in preparatory state related to cognitive effort in this task, which has similarly been linked to reward-network activity. Importantly, the contingent negative variation, which is linked to effortful cognitive preparation processes during cue-target intervals, was clearly observed in go trials but not in no-go trials. Moreover, target-locked ERP results (N1 and P3) suggested that attention to the target was enhanced when an action had to be performed (go trials), and typical inhibition-related ERP components were not observed in no-go trials, suggesting a lack of active response inhibition. Finally, feedback-related P3 results could suggest that correct feedback was valued more in motivated go trials, again implying that more effort was required to correctly perform the task. Together, these results indicate that the anticipation of action compared to inaction simultaneously entails differences in mental effort, highlighting the need for further dissociation of these concepts.

Schevernels H ，Bombeke K ，Krebs RM ，Boehler CN ... -  《-》

Long-lasting effects of performance-contingent unconscious and conscious reward incentives during cued task-switching.

Motivation is often thought to interact consciously with executive control, although recent studies have indicated that motivation can also be unconscious. To date, however, the effects of unconscious motivation on high-order executive control functions have not been explored. Only a few studies using subliminal stimuli (i.e., those not related to motivation, such as an arrow to prime a response) have reported short-lived effects on high-order executive control functions. Here, building on research on unconscious motivation, in which a behavior of perseverance is induced to attain a goal, we hypothesized that subliminal motivation can have long-lasting effects on executive control processes. We investigated the impact of unconscious/conscious monetary reward incentives on evoked potentials and neural activity dynamics during cued task-switching performance. Participants performed long runs of task-switching. At the beginning of each run, a reward (50 cents or 1 cent) was displayed, either subliminally or supraliminally. Participants earned the reward contingent upon their correct responses to each trial of the run. A higher percentage of runs was achieved with higher (conscious and unconscious) than lower rewards, indicating that unconscious high rewards have long-lasting behavioral effects. Event-related potential (ERP) results indicated that unconscious and conscious rewards influenced preparatory effort in task preparation, as suggested by a greater fronto-central contingent negative variation (CNV) starting at cue-onset. However, a greater parietal P3 associated with better reaction times (RTs) was observed only under conditions of conscious high reward, suggesting a larger amount of working memory invested during task performance. Together, these results indicate that unconscious and conscious motivations are similar at early stages of task-switching preparation but differ during task performance.

Capa RL ，Bouquet CA ，Dreher JC ，Dufour A ... -  《-》

Task preparation processes related to reward prediction precede those related to task-difficulty expectation.

Recently, attempts have been made to disentangle the neural underpinnings of preparatory processes related to reward and attention. Functional magnetic resonance imaging (fMRI) research showed that neural activity related to the anticipation of reward and to attentional demands invokes neural activity patterns featuring large-scale overlap, along with some differences and interactions. Due to the limited temporal resolution of fMRI, however, the temporal dynamics of these processes remain unclear. Here, we report an event-related potentials (ERP) study in which cued attentional demands and reward prospect were combined in a factorial design. Results showed that reward prediction dominated early cue processing, as well as the early and later parts of the contingent negative variation (CNV) slow-wave ERP component that has been associated with task-preparation processes. Moreover these reward-related electrophysiological effects correlated across participants with response time speeding on reward-prospect trials. In contrast, cued attentional demands affected only the later part of the CNV, with the highest amplitudes following cues predicting high-difficulty potential-reward targets, thus suggesting maximal task preparation when the task requires it and entails reward prospect. Consequently, we suggest that task-preparation processes triggered by reward can arise earlier, and potentially more directly, than strategic top-down aspects of preparation based on attentional demands.

Schevernels H ，Krebs RM ，Santens P ，Woldorff MG ，Boehler CN ... -  《-》

Teasing apart the anticipatory and consummatory processing of monetary incentives: An event-related potential study of reward dynamics.

The monetary incentive delay (MID) task has been widely used in fMRI studies to investigate the neural networks involved in anticipatory and consummatory reward processing. Previous efforts to adapt the MID task for use with ERPs, however, have had limited success. Here, we sought to further decompose reward dynamics using a comprehensive set of anticipatory (cue-N2, cue-P3, contingent negative variation [CNV]) and consummatory ERPs (feedback negativity [FN], feedback P3 [fb-P3]). ERP data was recorded during adapted versions of the MID task across two experiments. Unlike previous studies, monetary incentive cues modulated the cue-N2, cue-P3, and CNV; however, cue-related ERPs and the CNV were uncorrelated with one another, indicating distinct anticipatory subprocesses. With regard to consummatory processing, FN amplitude primarily tracked outcome valence (reward vs. nonreward), whereas fb-P3 amplitude primarily tracked outcome salience (uncertain vs. certain). Independent modulation of the cue-P3 and fb-P3 was observed, indicating that these two P3 responses may uniquely capture the allocation of attention during anticipatory and consummatory reward processing, respectively. Overall, across two samples, consistent evidence of both anticipatory and consummatory ERP activity was observed on an adapted version of the MID paradigm, demonstrating for the first time how these ERP components may be integrated with one another to more fully characterize the time course of reward processing. This ERP-MID paradigm is well suited to parsing reward dynamics, and can be applied to both healthy and clinical populations.

Novak KD ，Foti D 《-》

Modulation of ERP components by task instructions in a cued go/no-go task.

The present study investigated how components of ERPs are modulated when participants optimize speed versus accuracy in a cued go/no-go task. Using a crossover design, 35 participants received instructions to complete the task prioritizing response speed in half of the task, and accurate responding in the other half of the task. Analysis was performed on the contingent negative variation (CNV), P3go, and P3no-go and the corresponding independent components (IC), as identified by group independent component analysis. After speed instructions, the IC CNV(late), P3go(anterior), P3no-go(early), and P3no-go(late) all had larger amplitudes than after accuracy instructions. Furthermore, both the IC P3go(posterior) and IC P3go(anterior) had shorter latencies after speed than after accuracy instructions. The results demonstrate that components derived from the CNV and P3 components are facilitated when participants optimize response speed. These findings indicate that these ERP components reflect executive processes enabling adjustment of behavior to changing demands.

Aasen IE ，Brunner JF 《-》