A common neural system signaling the need for behavioral changes

Posterior medial frontal cortex regulates sympathy: A TMS study

Harm to some elicits greater sympathy than harm to others. Here, we examine the role of posterior medial frontal cortex (PMFC) in regulating sympathy, and explore the potential role of PMFC in the related phenomena of mentalizing and representing others as connected with oneself. We down-regulated either PMFC or a control region (middle temporal visual area), then assessed feelings of sympathy for and self-other overlap with two characters described as having suffered physical harm, and who were framed as adversarial or affiliative, respectively. We also measured mentalizing performance with regard to inferring the cognitive and affective states of the adversarial character. As hypothesized, down-regulating PMFC increased sympathy for both characters. Whereas we had predicted that down-regulating PMFC would decrease mentalizing ability given the postulated role of PMFC in the mentalizing network, participants in the PMFC down-regulation condition evinced greater second-order cognitive inference ability relative to controls. We observed no effect of the TMS manipulation on self-other overlap, although sympathy and self-other overlap were positively correlated. These findings are discussed as they may inform understanding of the functional role(s) of PMFC in regulating responses broadly linked with empathy.

Resting-State Functional Connectivity of the Punishment Network Associated With Conformity

Fear of punishment prompts individuals to conform. However, why some people are more inclined than others to conform despite being unaware of any obvious punishment remains unclear, which means the dispositional determinants of individual differences in conformity propensity are poorly understood. Here, we explored whether such individual differences might be explained by individuals' stable neural markers to potential punishment. To do this, we first defined the punishment network (PN) by combining all potential brain regions involved in punishment processing. We subsequently used a voxel-based global brain connectivity (GBC) method based on resting-state functional connectivity (FC) to characterize the hubs in the PN, which reflected an ongoing readiness state (i.e., sensitivity) for potential punishment. Then, we used the within-network connectivity (WNC) of each voxel in the PN of 264 participants to explain their tendency to conform by using a conformity scale. We found that a stronger WNC in the right thalamus, left insula, postcentral gyrus, and dACC was associated with a stronger tendency to conform. Furthermore, the FC among the four hubs seemed to form a three-phase ascending pathway, contributing to conformity propensity at every phase. Thus, our results suggest that task-independent spontaneous connectivity in the PN could predispose individuals to conform.

Posterior medial frontal cortex and threat-enhanced religious belief: a replication and extension

Research indicates that the posterior medial frontal cortex (pMFC) functions as a 'neural alarm' complex broadly involved in registering threats and helping to muster relevant responses. Holbrook and colleagues investigated whether pMFC similarly mediates ideological threat responses, finding that downregulating pMFC via transcranial magnetic stimulation (TMS) caused (i) less avowed religious belief despite being reminded of death and (ii) less group bias despite encountering a sharp critique of the national in-group. While suggestive, these findings were limited by the absence of a non-threat comparison condition and reliance on sham rather than control TMS. Here, in a pre-registered replication and extension, we downregulated pMFC or a control region (MT/V5) and then primed participants with either a reminder of death or a threat-neutral topic. As mentioned previously, participants reminded of death reported less religious belief when pMFC was downregulated. No such effect of pMFC downregulation was observed in the neutral condition, consistent with construing pMFC as monitoring for salient threats (e.g. death) and helping to recruit ideological responses (e.g. enhanced religious belief). However, no effect of downregulating pMFC on group bias was observed, possibly due to reliance on a collegiate in-group framing rather than a national framing as in the prior study.

Investigations into ventral prefrontal cortex using mediation models

The ventral prefrontal cortex (vPFC) is a major focus of investigation in neuroscience, particularly in the studies of emotion and emotion-cognition integration. A crucial question concerning the regulatory function of vPFC is how it is recruited, especially how the function maps onto the structure and determines appropriate behavior. In social exclusion studies, mediation model analyses suggest that vPFC regulates distress by disrupting anterior cingulate cortex (ACC) activities, whereas I recently report (Hu, 2018; Neuropsychologia) that ventral medial prefrontal cortex appears to defend the organism from acute stress by activating ACC. In this review, I synthesize and highlight functional imaging research with mediation analysis that over the past decades has begun to offer new insights into the brain mechanisms underlying vPFC. Toward this end, the first section of the paper outlines a model of the processes and neural systems involved in the interaction of emotion and cognition. The second and third sections survey recent research on emotional regulation with negative and positive pathways, respectively, emanating from vPFC. The fourth section summarizes the current dynamic network findings. Functional mediation analysis helps to identify signals within vPFC and others that are common and/or specific to particular information processing. Finally, I provide a personal perspective of the adoption of mediation model analysis in the investigations into vPFC.

Continuous Theta Burst Stimulation of the Posterior Medial Frontal Cortex to Experimentally Reduce Ideological Threat Responses

Decades of behavioral science research have documented functional shifts in attitudes and ideological adherence in response to various challenges, but little work to date has illuminated the neural mechanisms underlying these dynamics. This paper describes how continuous theta burst transcranial magnetic stimulation may be employed to experimentally assess the causal contribution of cortical regions to threat-related ideological shifts. In the example protocol provided here, participants are exposed to a threat prime-an explicit reminder of their own inevitable death and bodily decomposition-following a downregulation of the posterior medial frontal cortex (pMFC) or a sham stimulation. Next, disguised within a series of distracter tasks, participants' relative degree of ideological adherence is assessed-in the present example, with regard to coalitional prejudice and religious belief. Participants for whom the pMFC has been downregulated exhibit less coalitionally biased responses to an immigrant critical of the participants' national in-group, and less conviction in positive afterlife beliefs (i.e., God, angels, and heaven), despite having recently been reminded of death. These results complement prior findings that continuous theta burst stimulation of the pMFC influences social conformity and sharing and illustrate the feasibility of investigating the neural basis of high-level social cognitive shifts using transcranial magnetic stimulation.

Reduced error signalling in medication-naive children with ADHD: associations with behavioural variability and post-error adaptations

BACKGROUND

We examined the blood-oxygen level-dependent (BOLD) activation in brain regions that signal errors and their association with intraindividual behavioural variability and adaptation to errors in children with attention-deficit/hyperactivity disorder (ADHD).

METHODS

We acquired functional MRI data during a Flanker task in medication-naive children with ADHD and healthy controls aged 8-12 years and analyzed the data using independent component analysis. For components corresponding to performance monitoring networks, we compared activations across groups and conditions and correlated them with reaction times (RT). Additionally, we analyzed post-error adaptations in behaviour and motor component activations.

RESULTS

We included 25 children with ADHD and 29 controls in our analysis. Children with ADHD displayed reduced activation to errors in cingulo-opercular regions and higher RT variability, but no differences of interference control. Larger BOLD amplitude to error trials significantly predicted reduced RT variability across all participants. Neither group showed evidence of post-error response slowing; however, post-error adaptation in motor networks was significantly reduced in children with ADHD. This adaptation was inversely related to activation of the right-lateralized ventral attention network (VAN) on error trials and to task-driven connectivity between the cingulo-opercular system and the VAN.

LIMITATIONS

Our study was limited by the modest sample size and imperfect matching across groups.

CONCLUSION

Our findings show a deficit in cingulo-opercular activation in children with ADHD that could relate to reduced signalling for errors. Moreover, the reduced orienting of the VAN signal may mediate deficient post-error motor adaptions. Pinpointing general performance monitoring problems to specific brain regions and operations in error processing may help to guide the targets of future treatments for ADHD.

Neuromodulation of group prejudice and religious belief

People cleave to ideological convictions with greater intensity in the aftermath of threat. The posterior medial frontal cortex (pMFC) plays a key role in both detecting discrepancies between desired and current conditions and adjusting subsequent behavior to resolve such conflicts. Building on prior literature examining the role of the pMFC in shifts in relatively low-level decision processes, we demonstrate that the pMFC mediates adjustments in adherence to political and religious ideologies. We presented participants with a reminder of death and a critique of their in-group ostensibly written by a member of an out-group, then experimentally decreased both avowed belief in God and out-group derogation by downregulating pMFC activity via transcranial magnetic stimulation. The results provide the first evidence that group prejudice and religious belief are susceptible to targeted neuromodulation, and point to a shared cognitive mechanism underlying concrete and abstract decision processes. We discuss the implications of these findings for further research characterizing the cognitive and affective mechanisms at play.

The political (and physiological) divide: Political orientation, performance monitoring, and the anterior cingulate response

Our goal was to test a model of sociopolitical attitudes that posits a relationship between individual differences in liberal versus conservative political orientation and differential levels of anterior cingulate cortex (ACC) responsivity. We recorded event-related potentials (ERPs) while participants who varied along a unidimensional liberal-conservative continuum engaged in a standard Go/NoGo task. We also measured component attitudes of political orientation in the form of traditionalism (degree of openness to social change) and egalitarianism (a preference for social equality). Generally, participants who reported a more liberal political orientation made fewer errors and produced larger ACC-generated ERPs (the error-related negativity, or ERN and the NoGo N2). This ACC activation, especially as indicated by a larger NoGo N2, was most strongly associated with greater preference for social equality. Performance accuracy, however, was most strongly associated with greater openness to social change. These data are consistent with a social neuroscience view that sociopolitical attitudes are related to aspects of neurophysiological responsivity. They also indicate that a bidimensional model of political orientation can enhance our interpretation of the nature of these associations.

Neurophysiology of performance monitoring and adaptive behavior

Successful goal-directed behavior requires not only correct action selection, planning, and execution but also the ability to flexibly adapt behavior when performance problems occur or the environment changes. A prerequisite for determining the necessity, type, and magnitude of adjustments is to continuously monitor the course and outcome of one's actions. Feedback-control loops correcting deviations from intended states constitute a basic functional principle of adaptation at all levels of the nervous system. Here, we review the neurophysiology of evaluating action course and outcome with respect to their valence, i.e., reward and punishment, and initiating short- and long-term adaptations, learning, and decisions. Based on studies in humans and other mammals, we outline the physiological principles of performance monitoring and subsequent cognitive, motivational, autonomic, and behavioral adaptation and link them to the underlying neuroanatomy, neurochemistry, psychological theories, and computational models. We provide an overview of invasive and noninvasive systemic measures, such as electrophysiological, neuroimaging, and lesion data. We describe how a wide network of brain areas encompassing frontal cortices, basal ganglia, thalamus, and monoaminergic brain stem nuclei detects and evaluates deviations of actual from predicted states indicating changed action costs or outcomes. This information is used to learn and update stimulus and action values, guide action selection, and recruit adaptive mechanisms that compensate errors and optimize goal achievement.

Social manipulation of preference in the human brain

Our preferences are influenced by what other people like, but depend critically on how we feel about those people, a classical psychological effect called "cognitive balance." Here, we manipulated preferences for goods by telling participants the preferences of strongly liked or disliked groups of other people. Participants' preferences converged to those of the liked group, but diverged from the disliked group. Activation of dorsomedial prefrontal cortex (dmPFC) tracked the discrepancy between one's own preference and its social ideal and was associated with subsequent preference change (toward the liked and away from the disliked group), even several months later. A follow-up study found overlapping activation in this same region of dmPFC with negative monetary outcomes, but no overlap with nearby activations induced by response conflict. A single social encounter can thus result in long-lasting preference change, a mechanism that recruits dmPFC and that may reflect the aversive nature of cognitive imbalance.

Surprisingly correct: unexpectedness of observed actions activates the medial prefrontal cortex

Not only committing errors, but also observing errors has been shown to activate the dorsal medial prefrontal cortex, particularly BA 8 and adjacent rostral cingulate zone (RCZ). Currently, there is a debate on whether this activity reflects a response to the incorrectness of the committed action or to its unexpectedness. This article reports two studies investigating whether activity in BA 8/RCZ is due to the unexpectedness of observed errors or the incorrectness of the specific observed action. Both studies employed an action observation paradigm reliant on the observation of an actor tying sailing knots. The reported behavioral experiment delivered evidence that the paradigm successfully induced the expectation of incorrect actions as well as the expectation of correct actions. The functional magnetic resonance imaging study revealed that unexpectedly correct as well as unexpectedly incorrect actions activate the BA 8/RCZ. The same result was confirmed for a coordinate in the vicinity that has been previously reported to be activated in separate studies either by the error observation or by the unexpectedness of committed errors, and has been associated with the error-related negativity. The present results suggest that unexpectedness has an impact on the medial prefrontal correlate of observed errors.

Temporospatial dissociation of Pe subcomponents for perceived and unperceived errors

Previous research on performance monitoring revealed that errors are followed by an initial fronto-central negative deflection (error-related negativity, ERN or Ne) and a subsequent centro-parietal positivity (error positivity, Pe). It has been shown that error awareness mainly influences the Pe, whereas the ERN seems unaffected by conscious awareness of an error. The aim of the present study was to investigate the relation of ERN and Pe to error awareness in a visual size discrimination task in which errors are not elicited by impulsive responding but by perceptual difficulty. Further, we applied a temporospatial principal component analysis (PCA) to examine whether the temporospatial subcomponents of the Pe would differentially relate to error awareness. Event-related potential (ERP) results were in accordance with earlier studies: a significant error awareness effect was found for the Pe, but not for the ERN. Interestingly, a modulation with error perception on correct trials was found: correct responses considered as incorrect had larger correct-related negativity (CRN) and lager Pe amplitudes than correct responses considered as correct. The PCA yielded two relevant spatial factors accounting for the Pe (latency 300 ms). A temporospatial factor characterized by a centro-parietal positivity varied significantly with error awareness. Of the two temporospatial factors corresponding to ERN and CRN, one factor with central topography varied with response correctness and subjective error perception on correct responses. The PCA results indicate that the error awareness effect is specifically related to the centro-parietal subcomponent of the Pe. Since this component has also been shown to be related to the importance of an error, the present variation with error awareness indicates that this component is sensitive to the salience of an error and that salience secondarily may trigger error awareness.

May posterror performance be a critical factor for behavioral deficits in attention-deficit/hyperactivity disorder?

BACKGROUND

Although the performance of children with attention-deficit/hyperactivity disorder (ADHD) is impaired in a variety of cognitive tasks, the specific capacity of strategic readaptation after errors as a source of behavioral deficits is not sufficiently understood. This study used an extended and refined behavioral parameterization to assess performance monitoring and posterror adaptation in children with ADHD.

METHODS

Twenty-eight healthy control subjects and 47 ADHD patients (7-16 years of age, all males, matched for age and IQ) performed a visual flanker task in which targets were congruent or incongruent with preceding flankers. Posterror adaptation was measured for response speed (posterror slowing), accuracy, and variability by using normalized individual rates of change. Markers of error detection and general performance were also analyzed.

RESULTS

Postcorrect response speed and accuracy did not differ between the groups, in contrast to posterror behaviors. Whereas posterror slowing was not evident in any of the groups, the error rate and performance instability (reaction time variance) substantially increased after errors only in ADHD patients, not in control subjects. No reliable between-group differences were found for error detection and global performance.

CONCLUSIONS

In healthy children, posterror adaptation preserves performance at its ongoing level. No such adaptation was evident in ADHD, leading to consecutive errors and increased behavioral instability. Performance deficits in ADHD were only present after error but not after correct behaviors, which shapes the general profile of performance impairment in ADHD. The findings have practical implications for strategic designs of behavioral therapy in ADHD.

Independent oscillatory patterns determine performance fluctuations in children with attention deficit/hyperactivity disorder

The maintenance of stable goal-directed behaviour is a hallmark of conscious executive control in humans. Notably, both correct and error human actions may have a subconscious activation-based determination. One possible source of subconscious interference may be the default mode network that, in contrast to attentional network, manifests intrinsic oscillations at very low (<0.1 Hz) frequencies. In the present study, we analyse the time dynamics of performance accuracy to search for multisecond periodic fluctuations of error occurrence. Attentional lapses in attention deficit/hyperactivity disorder are proposed to originate from interferences from intrinsically oscillating networks. Identifying periodic error fluctuations with a frequency<0.1 Hz in patients with attention deficit/hyperactivity disorder would provide a behavioural evidence for such interferences. Performance was monitored during a visual flanker task in 92 children (7- to 16-year olds), 47 with attention deficit/hyperactivity disorder, combined type and 45 healthy controls. Using an original approach, the time distribution of error occurrence was analysed in the frequency and time-frequency domains in order to detect rhythmic periodicity. Major results demonstrate that in both patients and controls, error behaviour was characterized by multisecond rhythmic fluctuations with a period of ∼12 s, appearing with a delay after transition to task. Only in attention deficit/hyperactivity disorder, was there an additional 'pathological' oscillation of error generation, which determined periodic drops of performance accuracy each 20-30 s. Thus, in patients, periodic error fluctuations were modulated by two independent oscillatory patterns. The findings demonstrate that: (i) attentive behaviour of children is determined by multisecond regularities; and (ii) a unique additional periodicity guides performance fluctuations in patients. These observations may re-conceptualize the understanding of attentive behaviour beyond the executive top-down control and may reveal new origins of psychopathological behaviours in attention deficit/hyperactivity disorder.

Brain dynamics of upstream perceptual processes leading to visual object recognition: a high density ERP topographic mapping study

Recent studies suggest that visual object recognition is a proactive process through which perceptual evidence accumulates over time before a decision can be made about the object. However, the exact electrophysiological correlates and time-course of this complex process remain unclear. In addition, the potential influence of emotion on this process has not been investigated yet. We recorded high density EEG in healthy adult participants performing a novel perceptual recognition task. For each trial, an initial blurred visual scene was first shown, before the actual content of the stimulus was gradually revealed by progressively adding diagnostic high spatial frequency information. Participants were asked to stop this stimulus sequence as soon as they could correctly perform an animacy judgment task. Behavioral results showed that participants reliably gathered perceptual evidence before recognition. Furthermore, prolonged exploration times were observed for pleasant, relative to either neutral or unpleasant scenes. ERP results showed distinct effects starting at 280 ms post-stimulus onset in distant brain regions during stimulus processing, mainly characterized by: (i) a monotonic accumulation of evidence, involving regions of the posterior cingulate cortex/parahippocampal gyrus, and (ii) true categorical recognition effects in medial frontal regions, including the dorsal anterior cingulate cortex. These findings provide evidence for the early involvement, following stimulus onset, of non-overlapping brain networks during proactive processes eventually leading to visual object recognition.

Conscious perception of errors and its relation to the anterior insula

To detect erroneous action outcomes is necessary for flexible adjustments and therefore a prerequisite of adaptive, goal-directed behavior. While performance monitoring has been studied intensively over two decades and a vast amount of knowledge on its functional neuroanatomy has been gathered, much less is known about conscious error perception, often referred to as error awareness. Here, we review and discuss the conditions under which error awareness occurs, its neural correlates and underlying functional neuroanatomy. We focus specifically on the anterior insula, which has been shown to be (a) reliably activated during performance monitoring and (b) modulated by error awareness. Anterior insular activity appears to be closely related to autonomic responses associated with consciously perceived errors, although the causality and directions of these relationships still needs to be unraveled. We discuss the role of the anterior insula in generating versus perceiving autonomic responses and as a key player in balancing effortful task-related and resting-state activity. We suggest that errors elicit reactions highly reminiscent of an orienting response and may thus induce the autonomic arousal needed to recruit the required mental and physical resources. We discuss the role of norepinephrine activity in eliciting sufficiently strong central and autonomic nervous responses enabling the necessary adaptation as well as conscious error perception.

Motor and non-motor error and the influence of error magnitude on brain activity

It has been shown that frontal cortical areas increase their activity during error perception and error processing. However, it is not yet clear whether perception of motor errors is processed in the same frontal areas as perception of errors in cognitive tasks. It is also unclear whether brain activity level is influenced by the magnitude of error. For this purpose, we conducted a study in which subjects were confronted with motor and non-motor errors, and had them perform a sensorimotor transformation task in which they were likely to commit motor errors of different magnitudes (internal errors). In addition to the internally committed motor errors, non-motor errors (external errors) were added to the feedback in some trials. We found that activity in the anterior insula, inferior frontal gyrus (IFG), cerebellum, precuneus, and posterior medial frontal cortex (pMFC) correlated positively with the magnitude of external errors. The middle frontal gyrus (MFG) and the pMFC cortex correlated positively with the magnitude of the total error fed back to subjects (internal plus external). No significant positive correlation between internal error and brain activity could be detected. These results indicate that motor errors have a differential effect on brain activity compared with non-motor errors.

Genetic association studies of performance monitoring and learning from feedback: the role of dopamine and serotonin

Performance monitoring is essential for optimization of action outcomes. Research consistently implicates the posterior medial frontal cortex, particularly the rostral cingulate zone, in monitoring for unfavorable action outcomes, signaling the need for adjustments and learning from feedback. Current theories suggest that phasic dopaminergic signals coding unexpected positive or negative outcomes play a major role in this function. Here, I review EEG, neuroimaging and computational modeling studies making use of polymorphisms of candidate genes affecting neurotransmission, with a specific focus on dopamine. Although the evidence is still rather sparse, findings speak for a prominent role of dopamine in performance monitoring. However, the exact function in cortical areas underlying this function, such as the rostral cingulate zone, remains to be determined. Different hypotheses on the interaction of the rostral cingulate zone, the striatum, and the mesencephalic dopaminergic nuclei are discussed.

Self-identification and empathy modulate error-related brain activity during the observation of penalty shots between friend and foe

The ability to detect and process errors made by others plays an important role is many social contexts. The capacity to process errors is typically found to rely on sites in the medial frontal cortex. However, it remains to be determined whether responses at these sites are driven primarily by action errors themselves or by the affective consequences normally associated with their commission. Using an experimental paradigm that disentangles action errors and the valence of their affective consequences, we demonstrate that sites in the medial frontal cortex (MFC), including the ventral anterior cingulate cortex (vACC) and pre-supplementary motor area (pre-SMA), respond to action errors independent of the valence of their consequences. The strength of this response was negatively correlated with the empathic concern subscale of the Interpersonal Reactivity Index. We also demonstrate a main effect of self-identification by showing that errors committed by friends and foes elicited significantly different BOLD responses in a separate region of the middle anterior cingulate cortex (mACC). These results suggest that the way we look at others plays a critical role in determining patterns of brain activation during error observation. These findings may have important implications for general theories of error processing.

Probing human and monkey anterior cingulate cortex in variable environments

Previous research has identified the anterior cingulate cortex (ACC) as an important node in the neural network underlying decision making in primates. Decision making can, however, be studied under a large variety of circumstances, ranging from the standard well-controlled lab situation to more natural, stochastic settings, in which multiple agents interact. Here, we illustrate how these different varieties of decision making studied can influence theories ofACC function in monkeys. Converging evidence from unit recordings and lesion studies now suggest that the ACC is important for interpreting outcome information according to the current task context to guide future action selection. We then apply this framework to the study of human ACC function and discuss its potential implications.

The role of intact frontostriatal circuits in error processing

The basal ganglia have been suggested to play a key role in performance monitoring and resulting behavioral adjustments. It is assumed that the integration of prefrontal and motor cortico-striato-thalamo-cortical circuits provides contextual information to the motor anterior cingulate cortex regions to enable their function in performance monitoring. So far, direct evidence is missing, however. We addressed the involvement of frontostriatal circuits in performance monitoring by collecting event-related brain potentials (ERPs) and behavioral data in nine patients with focal basal ganglia lesions and seven patients with lateral prefrontal cortex lesions while they performed a flanker task. In both patient groups, the amplitude of the error-related negativity was reduced, diminishing the difference to the ERPs on correct responses. Despite these electrophysiological abnormalities, most of the patients were able to correct errors. Only in lateral prefrontal cortex patients whose lesions extended into the frontal white matter, disrupting the connections to the motor anterior cingulate cortex and the striatum, were error corrections severely impaired. In sum, the fronto-striato-thalamo-cortical circuits seem necessary for the generation of error-related negativity, even when brain plasticity has resulted in behavioral compensation of the damage. Thus, error-related ERPs in patients provide a sensitive measure of the integrity of the performance monitoring network.

A neural network reflecting individual differences in cognitive processing of emotions during perceptual decision making

Even simple perceptual decisions are influenced by the emotional content of a stimulus. Recent neuroimaging studies provide evidence about the neural mechanisms of perceptual decision making on emotional stimuli. However, the effect of individual differences in cognitive processing of emotions on perceptual decision making remains poorly understood. Here, we investigated how changes in the fMRI signal during perceptual decision making on facial stimuli covaried with individual differences in the ability to identify and communicate one's emotional state. Although this personality trait covaried with changes in activity in the dorsal anterior cingulate cortex (dACC) during gender decisions on facial expressions, there was no correlation during emotion decisions. Further, we investigated whether individual differences in the ability to cognitively process emotions depend on differences in the functional integration of emotional and cognitive brain regions. We therefore compared task-dependent changes in effective connectivity of dACC in individuals with good and with poor ability to cognitively process emotions using a psychophysiological interaction analysis. We found greater coupling of dACC with prefrontal regions in individuals with good ability to identify and communicate their emotional state. Conversely, individuals with poor ability in this domain showed greater coupling of dACC with the amygdala. Our data indicate that individual differences in the ability to identify and communicate one's emotional state are reflected by altered effective connectivity of the dACC with prefrontal and limbic regions. Thus, we provide neurophysiological evidence for a theoretical model that posits that a discommunication between limbic areas and the neocortex impairs cognitive processing of emotions.

The control of attention and actions: current research and future developments

In this introductory article of the special issue of Brain Research, we first present an overview of some general questions relating to cognitive control. For instance, one of the questions that remain to be answered is what control mechanisms and their neural underpinnings really 'do', beyond what is done by more basic 'computational' or data processing systems in the brain. We then briefly describe the four major issues addressed in the separate articles of this issue, namely attentional orienting, task set switching, performance and error monitoring, and response inhibition. In conclusion, we focus on some new methodological directions and illustrate how the study of cognitive control may be augmented by relatively newly emerging theoretical and empirical perspectives.

A model of the hierarchy of behaviour, cognition, and consciousness

Processes comparable in important respects to those underlying human conscious and non-conscious processing can be identified in a range of species and it is argued that these reflect evolutionary precursors of the human processes. A distinction is drawn between two types of processing: (1) stimulus-based and (2) higher-order. For 'higher-order,' in humans the operations of processing are themselves associated with conscious awareness. Conscious awareness sets the context for stimulus-based processing and its end-point is accessible to conscious awareness. However, the mechanics of the translation between stimulus and response proceeds without conscious control. The paper argues that higher-order processing is an evolutionary addition to stimulus-based processing. The model's value is shown for gaining insight into a range of phenomena and their link with consciousness. These include brain damage, learning, memory, development, vision, emotion, motor control, reasoning, the voluntary versus involuntary debate, and mental disorder.