Metacognitive Awareness of Difficulty in Action Selection: The Role of the Cingulo-opercular Network.

The question whether and how we are able to monitor our own cognitive states (metacognition) has been a matter of debate for decades. Do we have direct access to our cognitive processes, or can we only infer them indirectly based on their consequences? In the current study, we wanted to investigate the brain circuits that underlie the metacognitive experience of fluency in action selection. To manipulate action-selection fluency, we used a subliminal response priming paradigm. On each trial, both male and female human participants additionally engaged in the metacognitive process of rating how hard they felt it was to respond to the target stimulus. Despite having no conscious awareness of the prime, results showed that participants rated incompatible trials (during which subliminal primes interfered with the required response) to be more difficult than compatible trials (where primes facilitated the required response), reflecting metacognitive awareness of difficulty. This increased sense of subjective difficulty was mirrored by increased activity in the rostral cingulate zone and the anterior insula, two regions that are functionally closely connected. Importantly, this reflected activations that were unique to subjective difficulty ratings and were not explained by RTs or prime-response compatibility. We interpret these findings in light of a possible grounding of the metacognitive judgment of fluency in action selection in interoceptive signals resulting from increased effort.

Beyond asking: Exploring the use of automatic price evaluations to implicitly estimate consumers' willingness-to-pay.

Explicit consumers responses are often adverse for the validity of procedures used to estimate consumers' willingness-to-pay (WTP). This paper investigates if price evaluations occur automatically and to what extent these automatic processes can be used to implicitly estimate consumers' WTP. An adapted version of the task-rule congruency (TRC) paradigm was used in two studies. Results of the first study provided evidence for the notion that prices are automatically evaluated. However, the used procedure had limitations that restricted its utility as an implicit WTP estimate. The procedure was adjusted, and an additional study was conducted. The results of the second study also indicated that prices were evaluated automatically. Additionally, the procedure used during the second study allowed to explore to what extent the observed TRC effects could be used to implicitly estimate consumers' WTP. Taken together, these studies provided evidence for the notion that prices are evaluated automatically. Furthermore, the procedure has the potential to be further developed into an implicit estimate of consumers' WTP.

Anticipation of a mentally effortful task recruits Dorsolateral Prefrontal Cortex: An fNIRS validation study.

Preparing for a mentally demanding task calls upon cognitive and motivational resources. The underlying neural implementation of these mechanisms is receiving growing attention because of its implications for professional, social, and medical contexts. While several fMRI studies converge in assigning a crucial role to a cortico-subcortical network including Anterior Cigulate Cortex (ACC) and striatum, the involvement of Dorsolateral Prefrontal Cortex (DLPFC) during mental effort anticipation has yet to be replicated. This study was designed to target DLPFC contribution to anticipation of a difficult task using functional Near Infrared Spectroscopy (fNIRS), as a more cost-effective tool measuring cortical hemodynamics. We adapted a validated mental effort task, where participants performed easy and difficult mental calculation, and measured DLPFC activity during the anticipation phase. As hypothesized, DLPFC activity increased during anticipation of a hard task as compared to an easy task. Besides replicating previous fMRI work, these results establish fNIRS as an effective tool to investigate cortical contributions to anticipation of effortful behavior. This is especially useful if one requires testing large samples (e.g., to target individual differences), populations with contraindication for functional MRI (e.g., infants or patients with metal implants), or subjects in more naturalistic environments (e.g., work or sport).

An empirical comparison of different implicit measures to predict consumer choice.

While past research has found that implicit measures are good predictors of affectively driven, but not cognitively driven, behavior it has not yet been tested which implicit measures best predict behavior. By implementing a consumer context, in the present experiment, we assessed two explicit measures (i.e. self-reported habit and tastiness) and three implicit measures (i.e. manikin task, affective priming, ID-EAST) in order to test the predictive validity of affectively versus cognitively driven choices. The results indicate that irrespective of whether participants chose affectively or cognitively, both explicit measures, but not the implicit measures, predicted consumer choice very strongly. Likewise, when comparing the predictive validity among all measures, the explicit measures were the best predictors of consumer choice. Theoretical implications and limitations of the study are discussed.

Pattern Analyses Reveal Separate Experience-Based Fear Memories in the Human Right Amygdala.

Learning fear via the experience of contingencies between a conditioned stimulus (CS) and an aversive unconditioned stimulus (US) is often assumed to be fundamentally different from learning fear via instructions. An open question is whether fear-related brain areas respond differently to experienced CS-US contingencies than to merely instructed CS-US contingencies. Here, we contrasted two experimental conditions where subjects were instructed to expect the same CS-US contingencies while only one condition was characterized by prior experience with the CS-US contingency. Using multivoxel pattern analysis of fMRI data, we found CS-related neural activation patterns in the right amygdala (but not in other fear-related regions) that dissociated between whether a CS-US contingency had been instructed and experienced versus merely instructed. A second experiment further corroborated this finding by showing a category-independent neural response to instructed and experienced, but not merely instructed, CS presentations in the human right amygdala. Together, these findings are in line with previous studies showing that verbal fear instructions have a strong impact on both brain and behavior. However, even in the face of fear instructions, the human right amygdala still shows a separable neural pattern response to experience-based fear contingencies.SIGNIFICANCE STATEMENT In our study, we addressed a fundamental problem of the science of human fear learning and memory, namely whether fear learning via experience in humans relies on a neural pathway that can be separated from fear learning via verbal information. Using two new procedures and recent advances in the analysis of brain imaging data, we localized purely experience-based fear processing and memory in the right amygdala, thereby making a direct link between human and animal research.

There is more into 'doing' than 'knowing': The function of the right inferior frontal sulcus is specific for implementing versus memorising verbal instructions.

In the present study we examine the mechanism underlying the human ability to implement newly instructed stimulus-response mappings for their future application. We introduce a novel procedure in which we can investigate the processes underlying such implementation while controlling for more general working-memory demands. The results indicate that a region within the dorso-lateral prefrontal cortex (DLPFC) in the vicinity of the inferior frontal sulcus (IFS) is specifically recruited when new instructions are implemented compared to when new instructions are memorised. In addition, we observed that this area is more strongly activated when task performance is effective. Together, these findings suggest that the DLPFC, and more specific the IFS, plays an important role during the formation of procedural representations in working memory.

Influences of unconscious priming on voluntary actions: Role of the rostral cingulate zone.

The ability to make voluntary, free choices is fundamental to what it means to be human. A key brain region that is involved in free choices is the rostral cingulate zone (RCZ), which is part of the medial frontal cortex. Previous research has shown that activity in this brain region can be modulated by bottom-up information while making free choices. The current study extends those findings, and shows, for the first time, that activation in the RCZ can also be modulated by subliminal information. We used a subliminal response priming paradigm to bias free and cued choices. We observed more activation in the RCZ when participants made a choice that went against the prime's suggestion, compared to when they chose according to the prime. This shows that the RCZ plays an important role in overcoming externally-triggered conflict between different response options, even when the stimuli triggering this conflict are not consciously perceived. Our results suggest that an important mechanism of endogenous action in the RCZ may therefore involve exerting an internally-generated action choice against conflicting influences, such as external sensory evidence. We further found that subliminal information also modulated activity in the anterior insula and the supramarginal gyrus.

Voluntary inhibition of pain avoidance behavior: an fMRI study.

Behavioral inhibition has classically been considered to rely upon a neural network centered at the right inferior frontal cortex [rIFC; Aron et al. (8:170-177, 2004; 18:177-185, 2014)]. However, the vast majority of inhibition studies have entailed exogenous stop signals instructing participants to withhold responding. More recent work has begun to examine the neural underpinnings of endogenous inhibition, revealing a distinct cortical basis in the dorsal fronto-median cortex [dFMC; Brass and Haggard (27:9141-9145, 2007); Kühn et al. (30:2834-3843, 2009)]. Yet, contrary to everyday experiences of voluntary behavioral suppression, the paradigms employed to investigate action inhibition have thus far been somewhat artificial, and involve little persuasive motivation to act. Accordingly, the present fMRI study seeks to compare and contrast intentional with instructed inhibition in a novel pain paradigm that recruits 'hot' incentive response systems. Participants received increasing thermal stimulation to their inner wrists, and were required to occasionally withhold their natural impulse to withdraw from the compelling pain sensation at peak temperature, in both instructed and free-choice conditions. Consistent with previous research, we observed inhibition-related activity in the dFMC and the rIFC. However, these regions displayed equivalent activation levels for both inhibition types. These data extend previous research by demonstrating that under ecologically valid conditions with a strong motivation to act, both stopping networks operate in concert to enable suppression of unwanted behavior.

Happiness in action: the impact of positive affect on the time of the conscious intention to act.

The temporal relationship between our conscious intentions to act and the action itself has been widely investigated. Previous research consistently shows that the motor intention enters awareness a few 100 ms before movement onset. As research in other domains has shown that most behavior is affected by the emotional state people are in, it is remarkable that the role of emotional states on intention awareness has never been investigated. Here we tested the hypothesis that positive and negative affects have opposite effects on the temporal relationship between the conscious intention to act and the action itself. A mood induction procedure that combined guided imagery and music listening was employed to induce positive, negative, or neutral affective states. After each mood induction session, participants were asked to execute voluntary self-paced movements and to report when they formed the intention to act. Exposure to pleasant material, as compared to exposure to unpleasant material, enhanced positive affect and dampened negative affect. Importantly, in the positive affect condition participants reported their intention to act earlier in time with respect to action onset, as compared to when they were in the negative or in the neutral affect conditions. Conversely the reported time of the intention to act when participants experienced negative affect did not differ significantly from the neutral condition. These findings suggest that the temporal relationship between the conscious intention to act and the action itself is malleable to changes in affective states and may indicate that positive affect enhances intentional awareness.

The role of the striatum in effort-based decision-making in the absence of reward.

Decision-making involves weighing costs against benefits, for instance, in terms of the effort it takes to obtain a reward of a given magnitude. This evaluation process has been linked to the dorsal anterior cingulate cortex (dACC) and the striatum, with activation in these brain structures reflecting the discounting effect of effort on reward. Here, we investigate how cognitive effort influences neural choice processes in the absence of an extrinsic reward. Using functional magnetic resonance imaging in humans, we used an effort-based decision-making task in which participants were required to choose between two options for a subsequent flanker task that differed in the amount of cognitive effort. Cognitive effort was manipulated by varying the proportion of incongruent trials associated with each choice option. Choice-locked activation in the striatum was higher when participants chose voluntarily for the more effortful alternative but displayed the opposite trend on forced-choice trials. The dACC revealed a similar, yet only trend-level significant, activation pattern. Our results imply that activation levels in the striatum reflect a cost-benefit analysis, in which a balance is made between effort discounting and the intrinsic motivation to choose a cognitively challenging task. Moreover, our findings indicate that it matters whether this challenge is voluntarily chosen or externally imposed. As such, the present findings contrast with classical findings on effort discounting that found reductions in striatum activation for higher effort by finding enhancements of the same neural circuits when a cognitively challenging task is voluntarily selected and does not entail the danger of losing reward.

Component processes in voluntary task switching.

The present study investigated the involvement of bottom-up and top-down control in task-switching situations in which tasks are selected on a voluntary basis. We tested for indices of both types of control in the reduction in switch cost that is observed when more time is available before executing a task. Participants had to indicate their task choice overtly prior to the actual task execution, and two time intervals were manipulated: the interval between the task-execution response of the previous trial and task-indication response of the current trial and the interval between task-indication response and task-execution response of a particular trial. In Experiment 1, the length of these intervals was manipulated orthogonally, and indices for top-down and bottom-up control were observed. Concerned with the validity of these results, Experiments 2-3 additionally discouraged participants from preparing the upcoming task before their task-indication response. Indices for bottom-up control remained, but not for top-down control. The characteristics of top-down and bottom-up control in voluntary task switching and task switching in general are discussed.

Power to the will: how exerting physical effort boosts the sense of agency.

The sense of agency refers to the experience of being in control of one's actions and their consequences. The 19th century French philosopher Maine de Biran proposed that the sensation of effort might provide an internal cue for distinguishing self-caused from other changes in the environment. The present study is the first to empirically test the philosophical idea that effort promotes self-agency. We used intentional binding, which refers to the subjective temporal attraction between an action and its sensory consequences, as an implicit measure of the sense of agency. Effort was manipulated independent of the primary task by requiring participants to pull stretch bands of varying resistance levels. We found that intentional binding was enhanced under conditions of increased effort. This suggests not only that the experience of effort directly contributes to the sense of agency, but also that the integration of effort as an agency cue is non-specific to the effort requirement of the action itself.

Imaging volition: what the brain can tell us about the will.

The question of how we can voluntarily control our behaviour dates back to the beginnings of scientific psychology. Currently, there are two empirical research disciplines tackling human volition: cognitive neuroscience and social psychology. To date, there is little interaction between the two disciplines in terms of the investigation of human volition. The aim of the current article is to highlight recent brain imaging work on human volition and to relate social psychological concepts of volition to the functional neuroanatomy of intentional action. A host of studies indicate that the medial prefrontal cortex plays a crucial role in voluntary action. Accordingly, we postulate that social psychological concepts of volition can be investigated using neuroimaging techniques, and propose that by developing a social cognitive neuroscience of human volition, we may gain a deeper understanding of this fascinating and complex aspect of the human mind.

Biasing free choices: the role of the rostral cingulate zone in intentional control.

Humans have the ability to choose freely between different alternatives. It is common knowledge, however, that our free choices are influenced by the environment and by past experiences. In the present study we investigated if the involvement of the medial frontal cortex, which is known to be important for intentional control, depends on whether free choices are biased by past experiences. By using fMRI, we observed that the rostral cingulate zone (RCZ) is less activated during biased than during unbiased choices. On the basis of this finding we argue that the RCZ plays a specific role in intentional control of action by evaluating which alternative is most appropriate in a given context. In addition, we observed that free choices were biased more during mind wandering episodes than during on-task episodes. This finding suggests that during periods of mind wandering, attention is shifted away from the primary task and external factors can influence the choice process more easily.

A chain-retrieval model for voluntary task switching.

To account for the findings obtained in voluntary task switching, this article describes and tests the chain-retrieval model. This model postulates that voluntary task selection involves retrieval of task information from long-term memory, which is then used to guide task selection and task execution. The model assumes that the retrieved information consists of acquired sequences (or chains) of tasks, that selection may be biased towards chains containing more task repetitions and that bottom-up triggered repetitions may overrule the intended task. To test this model, four experiments are reported. In Studies 1 and 2, sequences of task choices and the corresponding transition sequences (task repetitions or switches) were analyzed with the help of dependency statistics. The free parameters of the chain-retrieval model were estimated on the observed task sequences and these estimates were used to predict autocorrelations of tasks and transitions. In Studies 3 and 4, sequences of hand choices and their transitions were analyzed similarly. In all studies, the chain-retrieval model yielded better fits and predictions than statistical models of event choice. In applications to voluntary task switching (Studies 1 and 2), all three parameters of the model were needed to account for the data. When no task switching was required (Studies 3 and 4), the chain-retrieval model could account for the data with one or two parameters clamped to a neutral value. Implications for our understanding of voluntary task selection and broader theoretical implications are discussed.

Valence, arousal, and cognitive control: a voluntary task-switching study.

The present study focused on the interplay between arousal, valence, and cognitive control. To this end, we investigated how arousal and valence associated with affective stimuli influenced cognitive flexibility when switching between tasks voluntarily. Three hypotheses were tested. First, a valence hypothesis that states that the positive valence of affective stimuli will facilitate both global and task-switching performance because of increased cognitive flexibility. Second, an arousal hypothesis that states that arousal, and not valence, will specifically impair task-switching performance by strengthening the previously executed task-set. Third, an attention hypothesis that states that both cognitive and emotional control ask for limited attentional resources, and predicts that arousal will impair both global and task-switching performance. The results showed that arousal affected task-switching but not global performance, possibly by phasic modulations of the noradrenergic system that reinforces the previously executed task. In addition, positive valence only affected global performance but not task-switching performance, possibly by phasic modulations of dopamine that stimulates the general ability to perform in a multitasking environment.

Persisting activation in voluntary task switching: it all depends on the instructions.

We tested the hypothesis that persisting activation from a previous task execution does not contribute to the switch cost in voluntary task switching. We reasoned that voluntary task switching requires the selection of random task sequences, which necessitates the active inhibition of previously executed tasks. The asymmetric switch cost was used as a marker for persisting activation. Participants switched voluntarily between color naming and word naming. One group was instructed to select unpredictable task sequences. The other group was not instructed to do so. When participants were instructed to be unpredictable, no asymmetric switch cost was observed. When participants were not instructed to be unpredictable, an asymmetric switch cost was observed. We conclude that the amount of persisting activation in voluntary task switching is limited and that the switch cost in voluntary task switching reflects the time needed for reconfiguring the cognitive system from one task to another rather than the time needed to compensate for persisting activation.

Voluntary task switching under load: contribution of top-down and bottom-up factors in goal-directed behavior.

The present study investigated the relative contribution of bottom-up and top-down control to task selection in the voluntary task-switching (VTS) procedure. In order to manipulate the efficiency of top-down control, a concurrent working memory load was imposed during VTS. In three experiments, bottom-up factors, such as stimulus repetitions, repetition of irrelevant information, and stimulus-task associations, were introduced in order to investigate their influence on task selection. We observed that the tendency to repeat tasks was stronger under load, suggesting that top-down control counteracts the automatic tendency to repeat tasks. The results also indicated that task selection can be guided by several elements in the environment, but that only the influence of stimulus repetitions depends on the efficiency of top-down control. The theoretical implications of these findings are discussed within the interplay between top-down and bottom-up control that underlies the voluntary selection of tasks.

Is advance reconfiguration in voluntary task switching affected by the design employed?

In task switching, when the amount of preparation time is increased, a reduction in switch cost or RISC effect is observed. This RISC effect is frequently attributed to advance reconfiguration processes. In the explicit task-cueing procedure, RISC effects are observed when varying the preparation time within participants but not when varying the preparation time across participants--a finding suggesting that RISC effects in the explicit task-cueing procedure are restricted to specific designs. The present study investigated RISC effects in voluntary task switching and compared RISC effects in a within-subjects design with RISC effects in a between-subjects design. Our results indicate that RISC effects are present in both designs. We conclude that advance reconfiguration in voluntary task switching is robust.

Investigating the role of conflict resolution in memory updating by means of the one-back choice RT task.

The current study is inspired by recent findings, which suggest that conflict is involved in the updating of memory representations. It directly addresses the relation between memory updating and conflict resolution by means of the one-back choice reaction time (RT) task, an updating task, which requires participants to postpone their response to stimulus n until the subsequent stimulus n + 1 has been presented. In three experiments, a more detailed analysis of the one-back choice RT task is presented in order to further identify the role of conflict resolution in memory updating. The findings demonstrate that the one-back choice RT task, which allows motor preparation just like a simple RT task, is in fact performed slower than a simple RT task because it additionally involves conflict resolution. It is further shown that also the response-stimulus interval of the one-back task involves processes that affect the amount of conflict in the task. In the "General discussion", the theoretical relevance of these findings for the concept of updating is discussed.