Contextual knowledge configures attentional control networks

To lie or to tell the truth? The influence of processing the opponent's feedback on the forthcoming choice

Introduction

The brain mechanisms of deceptive behavior are relatively well studied, and the key brain regions involved in its processing were established. At the same time, the brain mechanisms underlying the processes of preparation for deception are less known.

Methods

We studied BOLD-signal changes during the presentation of the opponent's feedback to a previous deceptive or honest action during the computer game. The goal of the game was to mislead the opponent either by means of deception or by means of telling the truth.

Results

As a result, it was shown that several brain regions that were previously demonstrated as involved in deception execution, such as the left anterior cingulate cortex and anterior insula, also underlie processes related to deception preparation.

Discussion

The results obtained also allowed us to suggest that brain regions responsible for performance monitoring, intention assessment, suppression of non-selected solutions, and reward processing could be involved in shaping future action selection and preparation for deception. By shedding light on the brain mechanisms underlying deception, our study contributes to a deeper understanding of this complex cognitive process. Furthermore, it emphasizes the significance of exploring brain mechanisms governing the choice between deception and truth at various stages of decision-making.

Task-independent neural bases of peer presence effect on cognition in children and adults

There is ample behavioral evidence that others' mere presence can affect any behavior in human and non-human animals, generally facilitating the expression of mastered responses while impairing the acquisition of novel ones. Much less is known about i) how the brain orchestrates the modulation of such a wide array of behaviors by others' presence and ii) when these neural underpinnings mature during development. To address these issues, fMRI data were collected in children and adults alternately observed and unobserved by a familiar peer. Subjects performed a numerosity comparison task and a phonological comparison task. While the former involves number-processing brain areas, the latter involves language-processing areas. Consistent with previous behavioral findings, adults' and children's performance improved in both tasks when observed by a peer. Across all participants, task-specific brain regions showed no reliable change in activity under peer observation. Rather, we found task-independent changes in domain-general brain regions typically involved in mentalizing, reward, and attention. Bayesian analyses singled out the attention network as the exception to the close child-adult resemblance of peer observation neural substrates. These findings suggest that i) social facilitation of some human education-related skills is primarily orchestrated by domain-general brain networks, rather than by task-selective substrates, and ii) apart from attention, peer presence neural processing is largely mature in children.

Resting State Dynamic Reconfiguration of Spatial Attention Cortical Networks and Visuospatial Functioning in Non-Verbal Learning Disability (NVLD): A HD-EEG Investigation

Nonverbal learning disability (NVLD) is a neurodevelopmental disorder characterized by deficits in visuospatial processing but spared verbal competencies. Neurocognitive markers may provide confirmatory evidence for characterizing NVLD as a separate neurodevelopmental disorder. Visuospatial performance and high-density electroencephalography (EEG) were measured in 16 NLVD and in 16 typically developing (TD) children. Cortical source modeling was applied to assess resting-state functional connectivity (rs-FC) in spatial attention networks (dorsal (DAN) and ventral attention networks (VAN)) implicated in visuospatial abilities. A machine-learning approach was applied to investigate whether group membership could be predicted from rs-FC maps and if these connectivity patterns were predictive of visuospatial performance. Graph theoretical measures were applied to nodes inside each network. EEG rs-FC maps in the gamma and beta band differentiated children with and without NVLD, with increased but more diffuse and less efficient functional connections bilaterally in the NVLD group. While rs-FC of the left DAN in the gamma range predicted visuospatial scores for TD children, in the NVLD group rs-FC of the right DAN in the delta range predicted impaired visuospatial performance, confirming that NVLD is a disorder with a predominant dysfunction in right hemisphere connectivity patterns.

Neural substrates underlying effortful control deficit in autism spectrum disorder: a meta-analysis of fMRI studies

Effortful control comprises attentional control, inhibitory control, and cognitive flexibility subprocesses. Effortful control is impaired in individuals with autism spectrum disorder, yet its neural underpinnings remain elusive. By conducting a coordinate-based meta-analysis, this study compared the brain activation patterns between autism and typically developing individuals and examined the effect of age on brain activation in each effortful control subprocesses. Meta-analytic results from 22 studies revealed that, individuals with autism showed hypoactivation in the default mode network for tasks tapping inhibitory control functioning (threshold-free cluster enhancement p < 0.001). When these individuals perform tasks tapping attentional control and cognitive flexibility, they exhibited aberrant activation in various brain networks including default mode network, dorsal attention, frontoparietal, visual and somatomotor networks (uncorrected ps < 0.005). Meta-regression analyses revealed that brain regions within the default mode network showed a significant decreasing trend in activation with increasing age (uncorrected p < 0.05). In summary, individuals with autism showed aberrant activation patterns across multiple brain functional networks during all cognitive tasks supporting effortful control, with some regions showing a decrease in activation with increasing age.

Left and right temporal-parietal junctions (TPJs) as "match/mismatch" hedonic machines: A unifying account of TPJ function

Experimental and theoretical studies have tried to gain insights into the involvement of the Temporal Parietal Junction (TPJ) in a broad range of cognitive functions like memory, attention, language, self-agency and theory of mind. Recent investigations have demonstrated the partition of the TPJ in discrete subsectors. Nonetheless, whether these subsectors play different roles or implement an overarching function remains debated. Here, based on a review of available evidence, we propose that the left TPJ codes both matches and mismatches between expected and actual sensory, motor, or cognitive events while the right TPJ codes mismatches. These operations help keeping track of statistical contingencies in personal, environmental, and conceptual space. We show that this hypothesis can account for the participation of the TPJ in disparate cognitive functions, including "humour", and explain: a) the higher incidence of spatial neglect in right brain damage; b) the different emotional reactions that follow left and right brain damage; c) the hemispheric lateralisation of optimistic bias mechanisms; d) the lateralisation of mechanisms that regulate routine and novelty behaviours. We propose that match and mismatch operations are aimed at approximating "free energy", in terms of the free energy principle of decision-making. By approximating "free energy", the match/mismatch TPJ system supports both information seeking to update one's own beliefs and the pleasure of being right in one's own' current choices. This renewed view of the TPJ has relevant clinical implications because the misfunctioning of TPJ-related "match" and "mismatch" circuits in unilateral brain damage can produce low-dimensional deficits of active-inference and predictive coding that can be associated with different neuropsychological disorders.

High-definition transcranial direct current stimulation modulates eye gaze on emotional faces in college students with alexithymia: An eye-tracking study

BACKGROUND

Atypical eye gaze on emotional faces is a core feature of alexithymia. The inferior frontal gyrus (IFG) is considered to be the neurophysiological basis of alexithymia-related emotional face fixation. Our aim was to examine whether anodal high-definition transcranial direct current stimulation (HD-tDCS) administered to the right (r)IFG would facilitate eye gaze of emotional faces in alexithymia individuals.

METHOD

Forty individuals with alexithymia were equally assigned to anodal or sham HD-tDCS of the rIFG according to the principle of randomization. The individuals then completed a free-viewing eye tracking task (including happy, sad, and neutral faces) before and after 5 consecutive days of stimulation (twice a day).

RESULTS

The results showed that twice a day anodal HD-tDCS of the rIFG significantly increased the fixation time and fixation count of the eye area on happy and neutral faces, but there was no significant effect on sad faces. According to the temporal-course analysis, after the intervention, the fixation time on neutral faces increased significantly at almost all time points of the eye tracking task. For happy faces, the improvement was demonstrated between 500 and 1000 ms and between 2500 and 3500 ms. For sad faces, the fixation time improved but not significantly.

CONCLUSIONS

Applying high-dose anodal HD-tDCS to the rIFG selectively facilitated eye gaze in the eye area of neutral and happy faces in individuals with alexithymia, which may improve their face processing patterns.

The functions of the temporal-parietal junction

In the human brain, the temporal-parietal junction (TPJ) is a histologically heterogenous area that includes the ventral portions of the parietal cortex and the caudal superior temporal gyrus sector adjacent to the posterior end of the Sylvian fissure. The anatomical heterogeneity of the TPJ is matched by its seemingly ubiquitous involvement in different cognitive functions that span from memory to language, attention, self-consciousness, and social behavior. In line with established clinical evidence, recent fMRI investigations have confirmed relevant hemispheric differences in the TPJ function. Most importantly, the same investigations have highlighted that, in each hemisphere, different subsectors of the TPJ are putatively involved in different cognitive functions. Here I review empirical evidence and theoretical proposals that were recently advanced to gain a unifying interpretation of TPJ function(s). In the final part of the review, a new overarching interpretation of the TPJ function is proposed. Current advances in cognitive neuroscience can provide important insights that help improve the clinical understanding of cognitive deficits experienced by patients with lesions centered in or involving the TPJ area.

Novel Cognitive Functions Arise at the Convergence of Macroscale Gradients

Functions in higher-order brain regions are the source of extensive debate. Although past trends have been to describe the brain-especially posterior cortical areas-in terms of a set of functional modules, a new emerging paradigm focuses on the integration of proximal functions. In this review, we synthesize emerging evidence that a variety of novel functions in the higher-order brain regions are due to convergence: convergence of macroscale gradients brings feature-rich representations into close proximity, presenting an opportunity for novel functions to arise. Using the TPJ as an example, we demonstrate that convergence is enabled via three properties of the brain: (1) hierarchical organization, (2) abstraction, and (3) equidistance. As gradients travel from primary sensory cortices to higher-order brain regions, information becomes abstracted and hierarchical, and eventually, gradients meet at a point maximally and equally distant from their sensory origins. This convergence, which produces multifaceted combinations, such as mentalizing another person's thought or projecting into a future space, parallels evolutionary and developmental characteristics in such regions, resulting in new cognitive and affective faculties.

The roles of the LpSTS and DLPFC in self-prioritization: A transcranial magnetic stimulation study

The Self‐Attention Network (SAN) has been proposed to describe the underlying neural mechanism of the self‐prioritization effect, yet the roles of the key nodes in the SAN—the left posterior superior temporal sulcus (LpSTS) and the dorsolateral prefrontal cortex (DLPFC)—still need to be clarified. One hundred and nine participants were randomly assigned into the LpSTS group, the DLPFC group, or the sham group. We used the transcranial magnetic stimulation (TMS) technique to selectively disrupt the functions of the corresponding targeted region, and observed its impacts on self‐prioritization effect based on the difference between the performance of the self‐matching task before and after the targeted stimulation. We analyzed both model‐free performance measures and HDDM‐based performance measures for the self‐matching task. The results showed that the inhibition of LpSTS could lead to reduced performance in processing self‐related stimuli, which establishes a causal role for the LpSTS in self‐related processing and provide direct evidence to support the SAN framework. However, the results of the DLPFC group from HDDM analysis were distinct from the results based on response efficiency. Our investigation further the understanding of the differentiated roles of key nodes in the SAN in supporting the self‐salience in information processing.

Dynamic Causal Modeling on the Identification of Interacting Networks in the Brain: A Systematic Review

Dynamic causal modeling (DCM) has long been used to characterize effective connectivity within networks of distributed neuronal responses. Previous reviews have highlighted the understanding of the conceptual basis behind DCM and its variants from different aspects. However, no detailed summary or classification research on the task-related effective connectivity of various brain regions has been made formally available so far, and there is also a lack of application analysis of DCM for hemodynamic and electrophysiological measurements. This review aims to analyze the effective connectivity of different brain regions using DCM for different measurement data. We found that, in general, most studies focused on the networks between different cortical regions, and the research on the networks between other deep subcortical nuclei or between them and the cerebral cortex are receiving increasing attention, but far from the same scale. Our analysis also reveals a clear bias towards some task types. Based on these results, we identify and discuss several promising research directions that may help the community to attain a clear understanding of the brain network interactions under different tasks.

Higher functional connectivity between prefrontal regions and the dorsal attention network predicts absence of renewal

Renewal describes the recovery of an extinguished response when extinction and recall contexts differ, demonstrating the context-dependency of extinction. The unexpected outcome change during extinction presumably directs attention to the context and promotes renewal. Accordingly, studies show that context processing for renewal is modulated by salience of and attention to context. Besides context-processing hippocampus, renewal involves ventromedial prefrontal cortex, orbitofrontal cortex and inferior frontal gyrus, which mediate response processing. Since showing renewal is a trait-like processing tendency, individuals with and without renewal may differ in resting-state functional connectivity of prefrontal regions with networks mediating attentional and salience processing. We analyzed resting-state functional MRI data from healthy participants (n = 70) of a non-fear-related contextual extinction task particularly suited for investigation of renewal. Participants without renewal exhibited significantly higher functional connectivity between prefrontal regions and bilateral intraparietal sulcus of the dorsal attention network. Functional connectivity between these regions correlated negatively with renewal level. Only in participants with renewal, the renewal level correlated positively with connectivity between left frontal eye field and several prefrontal regions. In contrast, functional connectivity of prefrontal regions with the salience network did not differ between groups. The results deliver first-time evidence for differences in resting-state functional connectivity between participants with and without renewal in non-fear-related extinction. Intraparietal-sulcus-guided top-down attentional control appears more strongly related to prefrontal activity in participants without renewal, and thus may have a role in their default processing mode of focusing on the stimulus and disregarding the context.

Brain Structure and Functional Connectivity Associated with Individual Differences in the Attentional Blink

The attentional blink (AB) has been central in characterizing the limit of temporal attention and consciousness. The neural mechanism of the AB is still in hot debate. With a large sample size, we combined multiple behavioral tests, multimodal MRI measures, and transcranial magnetic stimulation to investigate the neural basis underlying the individual differences in the AB. We found that AB magnitude correlated with the executive control functioning of working memory (WM) in behavior, which was fully mediated by T1 performance. Structural variations in the right temporoparietal junction (rTPJ) and its intrinsic functional connectivity with the left inferior frontal junction (lIFJ) accounted for the individual differences in the AB, which was moderated by the executive control of working memory. Disrupting the function of the lIFJ attenuated the AB deficit. Our findings clarified the neural correlates of the individual differences in the AB and elucidated its relationship with the consolidation-driven inhibitory control process.

Modulating the influence of recent trial history on attentional capture via transcranial magnetic stimulation (TMS) of right TPJ

In visual search, salient yet task-irrelevant distractors in the stimulus array interfere with target selection. This is due to the unwanted shift of attention towards the salient stimulus-the so-called attentional capture effect, which delays deployment of attention onto the target. Although powerful and automatic, attentional capture by a salient distractor is nonetheless antagonized by distractor-filtering mechanisms and is further modulated by cross-trial contingencies: The distractor cost is typically more robust when no distraction has been experienced in the immediate past, compared to when a distractor was present on the immediately preceding trial. Here, we used transcranial magnetic stimulation (TMS) to shed light on the causal role of two crucial nodes of the ventral attention network, namely the Temporo-Parietal Junction (TPJ) and the Middle Frontal Gyrus (MFG), in the exogenous control of attention (i.e., attentional capture) and its history-dependent modulation. Participants were asked to discriminate the direction of a target arrow while ignoring a task-irrelevant salient distractor, when present. Immediately after display onset, 10 Hz triple-pulse TMS was delivered either to TPJ or MFG on the right hemisphere. Results demonstrated that stimulation of right TPJ-but not of right MFG, strongly modulated attentional capture as a function of the type of previous trial, by somewhat enhancing the distractor-related cost when the preceding trial was a distractor-absent trial and significantly decreasing the cost when the preceding trial was a distractor-present trial. These findings indicate that TMS of right TPJ exacerbates the effect of the recent history, likely reflecting enhanced updating of the predictive model that dynamically governs proactive distractor-filtering mechanisms. More generally, the results attest to a role of TPJ in mediating the history-dependent modulation of attentional capture.

The age-related trajectory of visual attention neural function is altered in adults living with HIV: A cross-sectional MEG study

Background

Despite living a normal lifespan, at least 35% of persons with HIV (PWH) in resource-rich countries develop HIV-associated neurocognitive disorder (HAND). This high prevalence of cognitive decline may reflect accelerated ageing in PWH, but the evidence supporting an altered ageing phenotype in PWH has been mixed.

Methods

We examined the impact of ageing on the orienting of visual attention in PWH using dynamic functional mapping with magnetoencephalography (MEG) in 173 participants age 22–72 years-old (94 uninfected controls, 51 cognitively-unimpaired PWH, and 28 with HAND). All MEG data were imaged using a state-of-the-art beamforming approach and neural oscillatory responses during attentional orienting were examined for ageing, HIV, and cognitive status effects.

Findings

All participants responded slower during trials that required attentional reorienting. Our functional mapping results revealed HIV-by-age interactions in left prefrontal theta activity, alpha oscillations in the left parietal, right cuneus, and right frontal eye-fields, and left dorsolateral prefrontal beta activity (p<.005). Critically, within PWH, we observed a cognitive status-by-age interaction, which revealed that ageing impacted the oscillatory gamma activity serving attentional reorienting differently in cognitively-normal PWH relative to those with HAND in the left temporoparietal, inferior frontal gyrus, and right prefrontal cortices (p<.005).

Interpretation

This study provides key evidence supporting altered ageing trajectories across vital attention circuitry in PWH, and further suggests that those with HAND exhibit unique age-related changes in the oscillatory dynamics serving attention function. Additionally, our neural findings suggest that age-related changes in PWH may serve a compensatory function.

Funding

National Institutes of Health, USA.

A saliency-specific and dimension-independent mechanism of distractor suppression

During everyday tasks, salient distractors may capture our attention. Recently, it was shown that through implicit learning, capture by a salient distractor is reduced by suppressing the location where a distractor is likely to appear. In the current study, we presented distractors of different saliency levels at the same specific location, asking the question whether there is always one suppression level for a particular location or whether, for one location, suppression depends on the actual saliency of the distractor appearing at that location. In three experiments, we demonstrate a saliency-specific mechanism of distractor suppression, which can be flexibly modulated by the overall probability of encountering distractors of different saliency levels to optimize behavior in a specific environment. The results also suggest that this mechanism has dimension-independent aspects, given that the saliency-specific suppression pattern is unaffected when saliency signals of distractors are generated by different dimensions. It is argued that suppression is saliency-dependent, implying that suppression is modulated on a trial-by-trial basis contingent on the saliency of the actual distractor presented.

Lateralization, functional specialization, and dysfunction of attentional networks

The present review covers the latest findings on the lateralization of the dorsal and ventral attention systems, their functional specialization, and their clinical relevance for stroke-induced attentional dysfunction. First, the original assumption of a bilateral dorsal system for top-down attention and a right-lateralized ventral system for stimulus-driven attention is critically reviewed. The evidence for the involvement of the left parietal cortex in attentional functions is discussed and findings on putative pathways linking the dorsal and ventral network are presented. In the second part of the review, we focus on the different attentional subsystems and their lateralization, discussing the differences between spatial, feature- and object-based attention, and motor attention. We also review studies based on predictive coding frameworks of attentional functions. Finally, in the third section, we provide an overview of the consequences of specific disruption within the attention networks after stroke. The role of the interhemispheric (im)balance is discussed, and the results of new promising therapeutic approaches employing brain stimulation techniques such as transcranial magnetic stimulation (TMS) or transcranial direct current stimulation (tDCS) are presented.

The same, but different: Preserved distractor suppression in old age is implemented through an age-specific reactive ventral fronto-parietal network

Previous studies have shown age-related impairments in the ability to suppress salient distractors. One possibility is that this is mediated by age-related impairments in the recruitment of the left intraparietal sulcus (Left IPS), which has been shown to mediate the suppression of salient distractors in healthy, young participants. Alternatively, this effect may be due to a shift in engagement from proactive control to reactive control, possibly to compensate for age-related impairments in proactive control. Another possibility is that this is due to changes in the functional specificity of brain regions that mediate salience suppression, expressed in changes in spontaneous connectivity of these regions. We assessed these possibilities by having participants engage in a proactive distractor suppression task while in an fMRI scanner. Although we did not find any age-related differences in behavior, the young (N = 15) and older (N = 15) cohorts engaged qualitatively distinctive brain networks to complete the task. Younger participants engaged the predicted proactive control network, including the Left IPS. On the other hand, older participants simultaneously engaged both a proactive and a reactive network, but this was not a consequence of reduced network specificity as resting state functional connectivity was largely comparable in both age groups. Furthermore, improved behavioral performance for older adults was associated with increased resting state functional connectivity between these two networks. Overall, the results of this study suggest that age-related differences in the recruitment of a left lateralized ventral fronto-parietal network likely reflect the specific recruitment of reactive control mechanisms for distractor inhibition.

Deconstructing Reorienting of Attention: Cue Predictiveness Modulates the Inhibition of the No-target Side and the Hemispheric Distribution of the P1 Response to Invalid Targets

Orienting of attention produces a “sensory gain” in the processing of visual targets at attended locations and an increase in the amplitude of target-related P1 and N1 ERPs. P1 marks gain reduction at unattended locations; N1 marks gain enhancement at attended ones. Lateral targets that are preceded by valid cues also evoke a larger P1 over the hemisphere contralateral to the no-target side, which reflects inhibition of this side of space [Slagter, H. A., Prinssen, S., Reteig, L. C., & Mazaheri, A. Facilitation and inhibition in attention: Functional dissociation of pre-stimulus alpha activity, P1, and N1 components. Neuroimage, 125, 25–35, 2016]. To clarify the relationships among cue predictiveness, sensory gain, and the inhibitory P1 response, we compared cue- and target-related ERPs among valid, neutral, and invalid trials with predictive (80% valid/20% invalid) or nonpredictive (50% valid/50% invalid) directional cues. Preparatory facilitation over the visual cortex contralateral to the cued side of space (lateral directing attention positivity component) was reduced during nonpredictive cueing. With predictive cues, the target-related inhibitory P1 was larger over the hemisphere contralateral to the no-target side not only in response to valid but also in response to neutral and invalid targets: This result highlights a default inhibitory hemispheric asymmetry that is independent from cued orienting of attention. With nonpredictive cues, valid targets reduced the amplitude of the inhibitory P1 over the hemisphere contralateral to the no-target side whereas invalid targets enhanced the amplitude of the same inhibitory component. Enhanced inhibition was matched with speeded reorienting to invalid targets and drop in attentional costs. These findings show that reorienting of attention is modulated by the combination of cue-related facilitatory and target-related inhibitory activity.

The Impact of Cognitive Load on the Spatial Deployment of Visual Attention: Testing the Role of Interhemispheric Balance With Biparietal Transcranial Direct Current Stimulation

In healthy individuals, increasing cognitive load induces an asymmetric deployment of visuospatial attention, which favors the right visual space. To date, the neural mechanisms of this left/right attentional asymmetry are poorly understood. The aim of the present study was thus to investigate whether a left/right asymmetry under high cognitive load is due to a shift in the interhemispheric balance between the left and right posterior parietal cortices (PPCs), favoring the left PPC. To this end, healthy participants completed a visuospatial attention detection task under low and high cognitive load, whilst undergoing biparietal transcranial direct current stimulation (tDCS). Three different tDCS conditions were applied in a within-subjects design: sham, anodal left/cathodal right, and cathodal left/anodal right stimulation. The results revealed a left/right attentional asymmetry under high cognitive load in the sham condition. This asymmetry disappeared during cathodal left/anodal right tDCS, yet was not influenced by anodal left/cathodal right tDCS. There were no left/right asymmetries under low cognitive load in any of the conditions. Overall, these findings demonstrate that attentional asymmetries under high cognitive load can be modulated in a polarity-specific fashion by means of tDCS. They thus support the assumption that load-related asymmetries in visuospatial attention are influenced by interhemispheric balance mechanisms between the left and right PPCs.

Stria terminalis, amygdala, and temporoparietal junction networks facilitate efficient emotion processing under expectations

Rapid emotion processing is an ecologically essential ability for survival in social environments in which threatening or advantageous encounters dynamically and rapidly occur. Efficient emotion recognition is subserved by different processes, depending on one's expectations; however, the underlying functional and structural circuitry is still poorly understood. In this study, we delineate brain networks that subserve fast recognition of emotion in situations either congruent or incongruent with prior expectations. For this purpose, we used multimodal neuroimaging and investigated performance on a dynamic emotion perception task. We show that the extended amygdala structural and functional networks relate to speed of emotion processing under threatening conditions. Specifically, increased microstructure of the right stria terminalis, an amygdala white-matter pathway, was related to faster detection of emotion during actual presentation of anger or after cueing anger. Moreover, functional connectivity of right amygdala with limbic regions was related to faster detection of anger congruent with cue, suggesting selective attention to threat. On the contrary, we found that faster detection of anger incongruent with cue engaged the ventral attention "reorienting" network. Faster detection of happiness, in either expectancy context, engaged a widespread frontotemporal-subcortical functional network. These findings shed light on the functional and structural circuitries that facilitate speed of emotion recognition and, for the first time, elucidate a role for the stria terminalis in human emotion processing.

Identification of Visual Attentional Regions of the Temporoparietal Junction in Individual Subjects using a Vivid, Novel Oddball Paradigm

The Temporoparietal Junction (TPJ) of the cerebral cortex is a functionally heterogeneous region that also exhibits substantial anatomical variability across individuals. As a result, the precise functional organization of TPJ remains controversial. One or more regions within TPJ support visual attention processes, but the "attention TPJ" is difficult to functionally observe in individual subjects, and thus is typically identified by averaging across a large group of subjects. However, group-averaging also blurs localization and can obscure functional organization. Here, we develop and test an individual-subject approach to identifying attentional TPJ. This paradigm employs novel oddball images with a strong visual drive to produce robust TPJ responses in individuals. Vivid, novel oddballs drive responses in two TPJ regions bilaterally, a posterior region centered in posterior Superior Temporal Sulcus (TPJ_STS) and an anterior region in ventral Supramarginal Gyrus (TPJ_SMG). Although an attentional reorienting task fails to drive TPJ activation in individuals, group analysis of the attentional reorienting contrast reveals recruitment of right TPJ_STS, but not right TPJ_SMG. Similarly, right TPJ_STS, as identified in individual subjects by the vivid, novel oddball contrast, is activated by attentional reorienting, but right TPJ_SMG is not. These findings advance an individual-subject based approach to understanding the functional organization of TPJ.

The Neural Correlates of Consciousness and Attention: Two Sister Processes of the Brain

During the last three decades our understanding of the brain processes underlying consciousness and attention has significantly improved, mainly because of the advances in functional neuroimaging techniques. Still, caution is needed for the correct interpretation of these empirical findings, as both research and theoretical proposals are hampered by a number of conceptual difficulties. We review some of the most significant theoretical issues concerning the concepts of consciousness and attention in the neuroscientific literature, and put forward the implications of these reflections for a coherent model of the neural correlates of these brain functions. Even though consciousness and attention have an overlapping pattern of neural activity, they should be considered as essentially separate brain processes. The contents of phenomenal consciousness are supposed to be associated with the activity of multiple synchronized networks in the temporo-parietal-occipital areas. Only subsequently, attention, supported by fronto-parietal networks, enters the process of consciousness to provide focal awareness of specific features of reality.

Probing the Neural Mechanisms for Distractor Filtering and Their History-Contingent Modulation by Means of TMS

In visual search, the presence of a salient, yet task-irrelevant, distractor in the stimulus array interferes with target selection and slows down performance. Neuroimaging data point to a key role of the frontoparietal dorsal attention network in dealing with visual distractors; however, the respective roles of different nodes within the network and their hemispheric specialization are still unresolved. Here, we used transcranial magnetic stimulation (TMS) to evaluate the causal role of two key regions of the dorsal attention network in resisting attentional capture by a salient singleton distractor: the frontal eye field (FEF) and the cortex within the intraparietal sulcus (IPS). The task of the participants (male/female human volunteers) was to discriminate the pointing direction of a target arrow while ignoring a task-irrelevant salient distractor. Immediately after stimulus onset, triple-pulse 10 Hz TMS was delivered either to IPS or FEF on either side of the brain. Results indicated that TMS over the right FEF significantly reduced the behavioral cost engendered by the salient distractor relative to left FEF stimulation. No such effect was obtained with stimulation of IPS on either side of brain. Interestingly, this FEF-dependent reduction in distractor interference interacted with the contingent trial history, being maximal when no distractor was present on the previous trial relative to when there was one. Our results provide direct causal evidence that the right FEF houses key mechanisms for distractor filtering, pointing to a pivotal role of the frontal cortex of the right hemisphere in limiting interference from an irrelevant but attention-grabbing stimulus.SIGNIFICANCE STATEMENT Visually conspicuous stimuli attract our attention automatically and interfere with performance by diverting resources away from the main task. Here, we applied transcranial magnetic stimulation over four frontoparietal cortex locations (frontal eye field and intraparietal sulcus in each hemisphere) to identify regions of the dorsal attention network that help limit interference from task-irrelevant, salient distractors. Results indicate that the right FEF participates in distractor-filtering mechanisms that are recruited when a distracting stimulus is encountered. Moreover, right FEF implements adjustments in distraction-filtering mechanisms following recent encounters with distractors. Together, these findings indicate a different hemispheric contribution of the left versus right dorsal frontal cortex to distraction filtering. This study expands our understanding of how our brains select relevant targets in the face of task-irrelevant, salient distractors.

Asymmetric Dopaminergic Degeneration and Attentional Resources in Parkinson's Disease

Background: Attention is crucial to voluntary perform actions in Parkinson's disease (PD), allowing patients to bypass the impaired habitual motor control. The asymmetrical degeneration of the dopaminergic system could affect the attentional functions. Objective: To investigate the relationship between the asymmetric dopaminergic degeneration and the attentional resources in Parkinsonian patients with right-side (RPD) and left-side (LPD) motor symptoms predominance. Methods: 50 RPD, 50 LPD, and 34 healthy controls underwent visual (V), auditory (A), and multiple choices (MC) reaction time (RTs) tasks. For PD patients, these tasks were performed before and after a 4-week intensive, motor-cognitive rehabilitation treatment (MIRT). The effectiveness of treatment was evaluated assessing Unified Parkinson's disease Rating Scale (UPDRS) III and Timed-up and Go Test (TUG). Results: RTs did not differ between PD patients and healthy controls. Before MIRT, no differences between LPD and RPD patients were observed in RTs (p = 0.20), UPDRS III (p = 0.60), and TUG (p = 0.38). No differences in dopaminergic medication were found between groups (p = 0.44 and p = 0.66 before and after MIRT, respectively). After MIRT, LPD patients showed a significant reduction in MC RTs (p = 0.05), V RTs (p = 0.02), and MC-V RTs. A significant association between changes in RTs and improvements in UPDRS III and TUG was observed in LPD patients. Conclusion: attention does not differ among RPD patients, LPD patients and healthy controls. Only LPD patients improved their performances on attentional tasks after MIRT. We argue that the increased early susceptibility of the left nigrostriatal system to degeneration affects differently the cognitive modifiability and the neuroplastic potential. Our results could provide insight into new therapeutic approaches, highlighting the importance to design different treatments for RPD patients and LPD patients.

Spontaneous pre-stimulus oscillatory activity shapes the way we look: A concurrent imaging and eye-movement study

Previous behavioural studies have accrued evidence that response time plays a critical role in determining whether selection is influenced by stimulus saliency or target template. In the present work, we investigated to what extent the variations in timing and consequent oculomotor controls are influenced by spontaneous variations in pre-stimulus alpha oscillations. We recorded simultaneously brain activity using magnetoencephalography (MEG) and eye movements while participants performed a visual search task. Our results show that slower saccadic reaction times were predicted by an overall stronger alpha power in the 500 ms time window preceding the stimulus onset, while weaker alpha power was a signature of faster responses. When looking separately at performance for fast and slow responses, we found evidence for two specific sources of alpha activity predicting correct versus incorrect responses. When saccades were quickly elicited, errors were predicted by stronger alpha activity in posterior areas, comprising the angular gyrus in the temporal-parietal junction (TPJ) and possibly the lateral intraparietal area (LIP). Instead, when participants were slower in responding, an increase of alpha power in frontal eye fields (FEF), supplementary eye fields (SEF) and dorsolateral pre-frontal cortex (DLPFC) predicted erroneous saccades. In other words, oculomotor accuracy in fast responses was predicted by alpha power differences in more posterior areas, while the accuracy in slow responses was predicted by alpha power differences in frontal areas, in line with the idea that these areas may be differentially related to stimulus-driven and goal-driven control of selection.

Diametric effects of autism tendencies and psychosis proneness on attention control irrespective of task demands

Our capacity to attend a target while ignoring irrelevant distraction impacts our ability to successfully interact with our environment. Previous reports have sometimes identified excessive distractor interference in both autism and schizophrenia spectrum disorders and in neurotypical individuals with high subclinical expressions of these conditions. Independent of task, we show that the direction of the effect of autism or psychosis traits on the suppression or rejection of a non-target item is diametrical. In Study 1, in which the presence of a salient non-target item hindered performance, higher autism traits were associated with better performance, while higher psychosis traits were associated with worse performance. In Study 2, in which the presence of a salient non-target item facilitated performance, a complete reversal of effects was observed. Future clinical interventions may be informed by the context-specific advantages we observed for the autism and psychosis spectra, and by the need to consider the diametric effects they yield.

Cognitive benefit and cost of acute stress is differentially modulated by individual brain state

Acute stress is associated with beneficial as well as detrimental effects on cognition in different individuals. However, it is not yet known how stress can have such opposing effects. Stroop-like tasks typically show this dissociation: stress diminishes speed, but improves accuracy. We investigated accuracy and speed during a stroop-like task of 120 healthy male subjects after an experimental stress induction or control condition in a randomized, counter-balanced cross-over design; we assessed brain–behavior associations and determined the influence of individual brain connectivity patterns on these associations, which may moderate the effect and help identify stress resilience factors. In the mean, stress was associated to increase in accuracy, but decrease in speed. Accuracy was associated to brain activation in a distributed set of brain regions overlapping with the executive control network (ECN) and speed to temporo-parietal activation. In line with a stress-related large-scale network reconfiguration, individuals showing an upregulation of the salience and down-regulation of the executive-control network under stress displayed increased speed, but decreased performance. In contrast, individuals who upregulate their ECN under stress show improved performance. Our results indicate that the individual large-scale brain network balance under acute stress moderates cognitive consequences of threat.

Polarity-dependent Effects of Biparietal Transcranial Direct Current Stimulation on the Interplay between Target Location and Distractor Saliency in Visual Attention

Visual attention allows the allocation of limited neural processing resources to stimuli based on their behavioral priorities. The selection of task-relevant visual targets entails the processing of multiple competing stimuli and the suppression of distractors that may be either perceptually salient or perceptually similar to targets. The posterior parietal cortex controls the interaction between top-down (task-driven) and bottom-up (stimulus-driven) processes competing for attentional selection, as well as spatial distribution of attention. Here, we examined whether biparietal transcranial direct current stimulation (tDCS) would modulate the interaction between top-down and bottom-up processes in visual attention. Visual attention function was assessed with a visual discrimination task, in which a lateralized target was presented alone or together with a contralateral, similar or salient, distractor. The accuracy and RTs were measured before and during three stimulation sessions (sham, right anodal/left cathodal, left anodal/right cathodal). The analyses demonstrated (i) polarity-dependent effects of tDCS on the accuracy of target discrimination, but only when the target was presented with a similar distractor; (ii) the tDCS-triggered effects on the accuracy of discriminating targets, accompanied by a similar distractor, varied according to the target location; and (iii) overall detrimental effects of tDCS on RTs were observed, regardless of target location, distractor type, and polarity of the stimulation. We conclude that the observed polarity, distractor type, and target location-dependent effects of biparietal tDCS on the accuracy of target detection resulted from both a modulation of the interaction between top-down and bottom-up attentional processes and the interhemispheric competition mechanisms guiding attentional selection and spatial deployment of attention.

Opposing effects of memory-driven and stimulus-driven attention on distractor perception

It is well known that a match between working memory contents and a visual stimulus creates attentional bias toward the memory-matching stimulus. The present study investigated whether this memory-driven attentional bias exerts similar effects with conventional, spatial attention driven by a cue stimulus. Specifically, we examined how the effect of a distracting, task-irrelevant stimulus is modulated when attention was oriented toward the distractor in memory- and stimulus-driven manners. The results showed that significant interference by a distractor decreased when attention was allocated to the distractor in a memory-driven manner, whereas the distracter captured attention in a stimulus-driven manner exerted increased interference. By contrast, memory-driven attention brought an unattended stimulus into attentional focus, while stimulus-driven attention failed to do so. These results provide evidence that the mechanisms underlying working memory-driven and stimulus-driven attention are separable, pointing to the dynamic and flexible relationship between working memory and attention.

Neural basis of altered earlier attention and higher order biological motion processing in schizophrenia

Schizophrenia patients have impairments of biological motion (BM) perception, which provides critical information about social cognition. Because social cognition is underpinned by attention, the impairments of BM perception in schizophrenia could be partially attributable to altered attention. To elucidate the impairments in attention and social perception in schizophrenia, we investigated the neural basis of impaired BM processing using MRI in respect to attention deficits by eye tracker. Voxel-based morphometry was performed to evaluate the relationship between BM perception and gray matter (GM) volume. The temporo-parietal junction (TPJ) and anterior superior temporal sulcus (aSTS) were related to task accuracy. However, when the effect of attention (i.e., eye movement) was controlled, the relationship in TPJ became non-significant, while aSTS showed a significant relationship with BM perception. Alteration in TPJ might be associated with inefficient attentional strategy, whereas dysfunctional aSTS might be correlated with deficit in higher order BM processing per se. Several cognitive levels as well as corresponding brain areas are possibly involved in the manifestation of social cognitive deficits in schizophrenia.

Cognitive conflict increases processing of negative, task-irrelevant stimuli

The detection of cognitive conflict is thought to trigger adjustments in executive control. It has been recently shown that cognitive conflict increases processing of stimuli that are relevant to the ongoing task and that these modulations are exerted by the dorsolateral prefrontal cortex (DLPFC). However, it is still unclear whether such control influences are unspecific and might also affect the processing of task-irrelevant stimuli. The aim of the study was to examine if cognitive conflict affects processing of neutral and negative, task-irrelevant pictures. Participants responded to congruent (non-conflict) or to incongruent (conflict-eliciting) trials of a modified flanker task. Each response was followed by a presentation of a neutral or negative picture. The late positive potential (LPP) in response to picture presentation was used to assess the level of picture processing after conflict vs non-conflict trials. Connectivity between the DLPFC and attentional and perceptual areas during picture presentation was analysed to check if the DLPFC might be a source of these modulations. ERP results showed an effect of cognitive conflict only on processing of negative pictures: LPP in response to negative pictures was increased after conflict trials, whereas LPP in response to neutral pictures remained unchanged. Cortical connectivity analysis showed that conflict trials intensified information flow from the DLPFC towards attentional and perceptual regions. Results suggest that cognitive conflict increases processing of task-irrelevant stimuli; however, they must display high biological salience. Increase in cognitive control exerted by the DLPFC over attentional and perceptual regions is a probable mechanism of the effect.

Functional connectivity when detecting rare visual targets in schizophrenia

Individuals with schizophrenia demonstrate difficulties in attending to important stimuli (e.g., targets) and ignoring distractors (e.g., non-targets). We used a visual oddball task during fMRI to examine functional connectivity within and between the ventral and dorsal attention networks to determine the relative contribution of each network to detection of rare visual targets in schizophrenia. The sample comprised 25 schizophrenia patients and 27 healthy controls. Psychophysiological interaction analysis was used to examine whole-brain functional connectivity in response to targets. We used the right temporo parietal junction (TPJ) as the seed region for the ventral network and the right medial intraparietal sulcus (IPS) as the seed region for the dorsal network. We found that connectivity between right IPS and right anterior insula (AI; a component of the ventral network) was significantly greater in controls than patients. Expected patterns of within- and between-network connectivity for right TPJ were observed in controls, and not significantly different in patients. These findings indicate functional connectivity deficits between the dorsal and ventral attention networks in schizophrenia that may create problems in processing relevant versus irrelevant stimuli. Understanding the nature of network disruptions underlying cognitive deficits of schizophrenia may help shed light on the pathophysiology of this disorder.

Divergent functional connectivity during attentional processing in Lewy body dementia and Alzheimer's disease

Attention and executive dysfunction are features of Lewy body dementia (LBD) but their neuroanatomical basis is poorly understood. To investigate underlying dysfunctional attention-executive network (EXEC) interactions, we examined functional connectivity (FC) in 30 patients with LBD, 20 patients with Alzheimer's disease (AD), and 21 healthy controls during an event-related functional magnetic resonance imaging (fMRI) experiment. Participants performed a modified Attention Network Test (ANT), where they were instructed to press a button in response to the majority direction of arrows, which were either all pointing in the same direction or with one pointing in the opposite direction. Network activations during both target conditions and a baseline condition (no target) were derived by (ICA) Independent Component Analysis, and interactions between these networks were examined using the beta series correlations approach. Our study revealed that FC of ventral and dorsal attention networks DAN was reduced in LBD during all conditions, although most prominently during incongruent trials. These alterations in connectivity might be driven by a failure of engagement of ventral attention networks, and consequent over-reliance on the DAN. In contrast, when comparing AD patients with the other groups, we found hyperconnectivity between the posterior part of the default mode network (DMN) and the DAN in all conditions, particularly during incongruent trials. This might be attributable to either a compensatory effect to overcome DMN dysfunction, or be arising as a result of a disturbed transition of the DMN from rest to task. Our results demonstrate that dementia syndromes can be characterized both by hyper- and hypoconnectivity of distinct brain networks, depending on the interplay between task demand and available cognitive resources. However these are dependent upon the underlying pathology, which needs to be taken into account when developing specific cognitive therapies for LBD as compared to Alzheimer's.

Functional connectivity between prefrontal and parietal cortex drives visuo-spatial attention shifts

It is well established that the frontal eye-fields (FEF) in the dorsal attention network (DAN) guide top-down selective attention. In addition, converging evidence implies a causal role for the FEF in attention shifting, which is also known to recruit the ventral attention network (VAN) and fronto-striatal regions. To investigate the causal influence of the FEF as (part of) a central hub between these networks, we applied thetaburst transcranial magnetic stimulation (TBS) off-line, combined with functional magnetic resonance (fMRI) during a cued visuo-spatial attention shifting paradigm.

We found that TBS over the right FEF impaired performance on a visual discrimination task in both hemifields following attention shifts, while only left hemifield performance was affected when participants were cued to maintain the focus of attention. These effects recovered ca. 20 min post stimulation. Furthermore, particularly following attention shifts, TBS suppressed the neural signal in bilateral FEF, right inferior and superior parietal lobule (IPL/SPL) and bilateral supramarginal gyri (SMG). Immediately post stimulation, functional connectivity was impaired between right FEF and right SMG as well as right putamen. Importantly, the extent of decreased connectivity between right FEF and right SMG correlated with behavioural impairment following attention shifts.

The main finding of this study demonstrates that influences from right FEF on SMG in the ventral attention network causally underly attention shifts, presumably by enabling disengagement from the current focus of attention.

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Thetaburst stimulation to the right FEF temporarily impairs bilateral attention shifts.

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Lateralised behavioural deficits in the contralateral hemifield are observed when cued to maintain attention.

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These effects recover ca. 20 min post stimulation.

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During shifts, neural activity is suppressed following right FEF TBS in the dorsal attention network and supramarginal gyri.

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Influences from right FEF to SMG causally underlie attention shifts, presumably by enabling disengagement from current focus.

Presaccadic target competition attenuates distraction

Although it is well known that salient nontargets can capture attention despite being task irrelevant, several studies have reported short fixation dwell times, suggesting the presence of an attentional mechanism to "rapidly reject" dissimilar distractors. Rapid rejection has been hypothesized to depend on the strong mismatch between distractor features and the target template, but it is unknown whether the presence of strong feature mismatch is sufficient, or if the presence of a target at a competing location is also necessary. Here, we investigated this question by first replicating the finding of rapid rejection for dissimilar distractors in the presence of a concurrent target (Experiment 1); manipulating the onset of the target stimulus relative to the distractor (Experiment 2); and using a saccade-contingent display to delay the target onset until after the first saccade was initiated. The results demonstrate that the speed of distractor rejection depends on the presence of target competition prior to the initiation of the first saccade, and not after the saccade. This suggests that stimulus competition for covert attention sets a "saccade priority map" that unfolds over time, resulting in faster corrective saccades to an anticipated object with higher top-down attentional priority.

Isolating response inhibition in the brain: Parietal versus frontal contribution

Response inhibition is a main function of cognitive control and its neural substrates have been studied extensively. However, it is still a question whether previous brain imaging investigations were successful in isolating specific response inhibition activation. In the current study we attempted to pinpoint response inhibition in the brain using a Go/No-go task and fMRI, by contrasting rare-No-go trials with prevalent-No-go trials. Although inhibition is required in all No-go trials, task variants with rare-No-go cases (25%) create a prepotent response which elicits a strong demand for inhibition, while task variants with prevalent-No-go cases (75%) require very little inhibition effort. Since the neural activation in this design is extracted solely from No-go trials, differing only in the extent of inhibitory demand, the analysis avoids contamination of the data with motor effects or visual factors. Using this experimental design we highlight the contribution of the parietal cortex (bilaterally) to inhibitory processes, while casting doubts about the specificity of frontal activation in such processes. Future studies are required to verify that bilateral intraparietal sulcus and left temporo-parietal junction activations could be markers of inhibitory control.

Individual attentional selection capacities are reflected in interhemispheric connectivity of the parietal cortex

Modelling psychophysical data using the Theory of Visual Attention (TVA) allows for a quantification of attentional sub-processes, such as the resolution of competition amongst multiple stimuli by top-down control signals for target selection (TVA-parameter α). This fMRI study investigated the neural correlates of α by comparing activity differences and changes of effective connectivity between conditions where a target was accompanied by a distractor or by a second target. Twenty-five participants performed a partial report task inside the MRI scanner. The left angular gyrus (ANG), medial frontal, and posterior cingulate cortex showed higher activity when a target was accompanied by a distractor as opposed to a second target. The reverse contrast yielded activation of a bilateral fronto-parietal network, the anterior insula, anterior cingulate cortex, and left inferior occipital gyrus. A psychophysiological interaction analysis revealed that the connectivity between left ANG and the left and right supramarginal gyrus (SMG), left anterior insula, and right putamen was enhanced in the target-distractor condition in participants with worse attentional top-down control. Dynamic causal modelling suggested that the connection from left ANG to right SMG during distractor presence was modulated by α. Our data show that interindividual differences in attentional processing are reflected in changes of effective connectivity without significant differences in activation strength of network nodes.

Neural Processes in the Human Temporoparietal Cortex Separated by Localized Independent Component Analysis

The human temporoparietal junction (TPJ) is a topic of intense research. Imaging studies have identified TPJ activation in association with many higher-order functions such as theory-of-mind, episodic memory, and attention, causing debate about the distribution of different processes. One major challenge is the lack of consensus about the anatomical location and extent of the TPJ. Here, we address this problem using data-driven analysis to test the hypothesis that the bilateral TPJ can be parcellated into subregions. We applied independent component analysis (ICA) to task-free fMRI data within a local region around the bilateral TPJ, iterating the ICA at multiple model orders and in several datasets. The localized analysis allowed finer separation of processes and the use of multiple dimensionalities provided qualitative information about lateralization. We identified four subdivisions that were bilaterally symmetrical and one that was right biased. To test whether the independent components (ICs) reflected true subdivisions, we performed functional connectivity analysis using the IC coordinates as seeds. This confirmed that the subdivisions belonged to distinct networks. The right-biased IC was connected with a network often associated with attentional processing. One bilateral subdivision was connected to sensorimotor regions and another was connected to auditory regions. One subdivision that presented as distinct left- and right-biased ICs was connected to frontoparietal regions. Another subdivision that also had left- and right-biased ICs was connected to social or default mode networks. Our results show that the TPJ in both hemispheres hosts multiple neural processes with connectivity patterns consistent with well developed specialization and lateralization.

A critical role of temporoparietal junction in the integration of top-down and bottom-up attentional control

Information processing can be biased toward behaviorally relevant and salient stimuli by top-down (goal-directed) and bottom-up (stimulus-driven) attentional control processes respectively. However, the neural basis underlying the integration of these processes is not well understood. We employed functional magnetic resonance imaging (fMRI) and transcranial direct-current stimulation (tDCS) in humans to examine the brain mechanisms underlying the interaction between these two processes. We manipulated the cognitive load involved in top-down processing and stimulus surprise involved in bottom-up processing in a factorial design by combining a majority function task and an oddball paradigm. We found that high cognitive load and high surprise level were associated with prolonged reaction time compared to low cognitive load and low surprise level, with a synergistic interaction effect, which was accompanied by a greater deactivation of bilateral temporoparietal junction (TPJ). In addition, the TPJ displayed negative functional connectivity with right middle occipital gyrus, which is involved in bottom-up processing (modulated by the interaction effect), and the right frontal eye field (FEF), which is involved in top-down control. The enhanced negative functional connectivity between the TPJ and right FEF was accompanied by a larger behavioral interaction effect across subjects. Application of cathodal tDCS over the right TPJ eliminated the interaction effect. These results suggest that the TPJ plays a critical role in processing bottom-up information for top-down control of attention.

Differential functional brain network connectivity during visceral interoception as revealed by independent component analysis of fMRI TIME-series

Influential theories of brain-viscera interactions propose a central role for interoception in basic motivational and affective feeling states. Recent neuroimaging studies have underlined the insula, anterior cingulate, and ventral prefrontal cortices as the neural correlates of interoception. However, the relationships between these distributed brain regions remain unclear. In this study, we used spatial independent component analysis (ICA) and functional network connectivity (FNC) approaches to investigate time course correlations across the brain regions during visceral interoception. Functional magnetic resonance imaging (fMRI) was performed in thirteen healthy females who underwent viscerosensory stimulation of bladder as a representative internal organ at different prefill levels, i.e., no prefill, low prefill (100 ml saline), and high prefill (individually adapted to the sensations of persistent strong desire to void), and with different infusion temperatures, i.e., body warm (∼37°C) or ice cold (4-8°C) saline solution. During Increased distention pressure on the viscera, the insula, striatum, anterior cingulate, ventromedial prefrontal cortex, amygdalo-hippocampus, thalamus, brainstem, and cerebellar components showed increased activation. A second group of components encompassing the insula and anterior cingulate, dorsolateral prefrontal and posterior parietal cortices and temporal-parietal junction showed increased activity with innocuous temperature stimulation of bladder mucosa. Significant differences in the FNC were found between the insula and amygdalo-hippocampus, the insula and ventromedial prefrontal cortex, and the ventromedial prefrontal cortex and temporal-parietal junction as the distention pressure on the viscera increased. These results provide new insight into the supraspinal processing of visceral interoception originating from an internal organ.

The interaction between self-bias and reward: Evidence for common and distinct processes

The perceptual matching of shapes and labels can be affected by both self- and reward-biases when shapes are linked either to labels referring to particular individuals (you, friend, stranger) or to different reward values (£8, £2, £0). We investigated the relations between these biases by varying the reward value associated with particular shape-label pairs (circle-you, square-friend, triangle-stranger). Self shape-label pairs (circle-you) always received no reward, while friend shape-label pairs (square-friend) received high reward and stranger shape-label pairs low reward (triangle-stranger), or the reverse (friend-low reward; stranger-high reward). Despite receiving no reward, responses to self-related pairs were advantaged relative to those to low-reward stimuli and did not differ from those to high-reward items. There was also an advantage for responses to high-reward friend pairs relative to low-reward stranger stimuli, and for high-reward stranger stimuli compared to low-reward friends. Correlations across individuals were found across trial blocks for both the self-advantage and the high-reward advantage, but the self- and reward-advantages were uncorrelated. This suggests that the self- and reward-advantage effects have different origins. In addition, the magnitude of the self-advantage varied according to the rated personal distance between a participant and a stranger. For individuals manifesting a close personal distance to strangers, the self-advantage was smaller, and sensitivity to reward influenced the difference between the self- and high-reward conditions. For individuals manifesting a large personal distance to strangers, sensitivity to reward did not affect self-matching. We suggest that self-advantages on perceptual matching arise independent of reward for individuals with a large personal distance to strangers. On the other hand, in individuals with a weak self-bias, high reward and the self modulate a common subjective value system.