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Congruency monitoring of action occurs in individuals with relevant motor experience while observing actions. However, it remains unclear whether congruency monitoring can occur at the motor level and the extent to which expertise contributes. Here, we examined the behavioral performance and electrophysiological brain activity of individuals with and without domain-specific expertise when judging the action congruency of occluded video clips of a snowboard halfpipe trick and normal walking. For the halfpipe trick, experts exhibited better task performance and greater midline theta oscillations before possible incongruency compared with controls. Source reconstruction for the theta oscillation revealed a stronger activation in the middle and superior frontal gyrus for experts in response to incongruency compared with controls. Incongruent halfpipe actions elicited a higher N400 amplitude in experts compared with congruent actions, while no such differences were observed in controls. Source reconstruction revealed the activation in the board frontal regions and middle temporal gyrus for experts. These findings suggest that congruency monitoring can occur at the motor level during action observations and is modulated by individual expertise. The modulation of expertise reflects in the special N400 effect and midline theta oscillation.

It is now well recognised that human semantic knowledge is supported by a large neural network distributed over multiple brain regions, but the dynamic organisation of this network remains unknown. Some studies have proposed that a central semantic hub coordinates this network. We explored the possibility of different types of semantic hubs; namely “representational hubs”, whose neural activity is modulated by semantic variables, and “connectivity hubs”, whose connectivity to distributed areas is modulated by semantic variables. We utilised the spatio-temporal resolution of source-estimated Electro-/Magnetoencephalography data in a word-concreteness task (17 participants, 12 female) in order to: (i) find representational hubs at different timepoints based on semantic modulation of evoked brain activity in source space; (ii) identify connectivity hubs among left Anterior Temporal Lobe (ATL), Angular Gyrus (AG), Middle Temporal Gyrus and Inferior Frontal Gyrus based on their functional connectivity to the whole cortex, in particular sensory-motor-limbic systems; and (iii) explicitly compare network models with and without an intermediate hub linking sensory input to other candidate hub regions using Dynamic Causal Modelling (DCM) of evoked responses. ATL’s activity was modulated as early as 150ms post-stimulus, while both ATL and AG showed modulations of functional connectivity with sensory-motor-limbic areas from 150-450ms. DCM favoured models with one intermediate hub, namely ATL in an early time window and AG in a later time-window. Our results support ATL as a single representational hub with an early onset, but suggest that both ATL and AG function as connectivity hubs depending on the stage of semantic processing.

Background The ability to recognize whether sensory consequences have been self-generated or externally produced is an important element of motor control and self-monitoring. Deficits in self-monitoring have been proposed to cause abnormal bodily experiences and psychotic symptoms such as hallucinations. A recent study designed a robotic system that applies sensorimotor stimulation in healthy subjects and safely induces mild presence hallucinations (PH) and passivity experiences (Blanke et al., 2014). PH are defined as the sensation that someone is close by when actually no one is present and passivity experiences are characterized by perceptions or beliefs that an external agent is controlling one’s actions, perceptions, and/or thoughts. Although, both symptoms occur in schizophrenia and Parkinson’s disease, their neural mechanisms are unknown. Methods Here, we first investigated the neural mechanisms of PH and passivity experiences in 25 healthy subjects. We developed a new MR-compatible robotic system able to generate the aforementioned sensorimotor conflicts, while recording subjects’ brain activity using fMRI. In addition, we applied lesion network mapping to 11 neurological patients with symptomatic PH and compared both populations to find a common PH network. In a final step, we investigated the relevance of the PH network by analyzing the connectivity of the PH network in resting state fMRI data from 58 psychotic patients. Results We first evaluated the regions associated with the general sensorimotor conflict, which revealed the left sensorimotor area, the left putamen, the right inferior parietal lobule and the right cerebellum. Then, we analyzed the regions that were more activated during the condition eliciting PH and passivity experiences and found the inferior frontal gyrus (IFG), the insula, the superior medial gyrus and the middle temporal gyrus (MTG). Comparison of these two networks with the symptomatic PH network in neurological patients highlighted the IFG, the MTG and the vPMc. The resting state analysis within those regions in psychotic patients revealed no global differences between the groups but a functional connectivity decrease between MTG and IFG (bilaterally) specific for psychotic patients experiencing passivity experiences. Discussion Collectively, we showed that through the use of a robotic system generating sensorimotor conflicts, the neural correlates of induced-PH and passivity experiences can be studied in healthy subjects in a controlled manner. In addition, we found two networks associated with induced-PH and passivity experience. Of these regions, three were also recruited in patients with PH of neurological origin, forming the PH network. MTG-IFG connectivity in the PH network was altered selectively in psychotic patients with passivity experiences, revealing the relevance of the neural mechanisms of PH and passivity experiences in psychosis.

Semantic judgments involve both representations of meaning plus executive mechanisms that guide knowledge retrieval in a taskappropriate way. These 2 components of semantic cognition— representation and control—are commonly linked to left temporal and prefrontal cortex, respectively. This simple proposal, however, remains contentious because in most functional neuroimaging studies to date, the number of concepts being activated and the involvement of executive processes during retrieval are confounded. Using functional magnetic resonance imaging, we examined a task in which semantic representation and control demands were dissociable. Words with multiple meanings like ‘‘bank’’ served as targets in a double-prime paradigm, in which multiple meaning activation and maximal executive demands loaded onto different priming conditions. Anterior inferior temporal gyrus (ITG) was sensitive to the number of meanings that were retrieved, suggesting a role for this region in semantic representation, while posterior middle temporal gyrus (pMTG) and inferior frontal cortex showed greater activation in conditions that maximized executive demands. These results support a functional dissociation between left ITG and pMTG, consistent with a revised neural organization in which left prefrontal and posterior temporal areas work together to underpin aspects of semantic control.

Differential processing of threat can consummate as early as 100 ms post-stimulus. Moreover, early perception not only differentiates threat from non-threat stimuli but also distinguishes among discrete threat subtypes (e.g. fear, disgust and anger). Combining spatial-frequency-filtered images of fear, disgust and neutral scenes with high-density event-related potentials and intracranial source estimation, we investigated the neural underpinnings of general and specific threat processing in early stages of perception. Conveyed in low spatial frequencies, fear and disgust images evoked convergent visual responses with similarly enhanced N1 potentials and dorsal visual (middle temporal gyrus) cortical activity (relative to neutral cues; peaking at 156 ms). Nevertheless, conveyed in high spatial frequencies, fear and disgust elicited divergent visual responses, with fear enhancing and disgust suppressing P1 potentials and ventral visual (occipital fusiform) cortical activity (peaking at 121 ms). Therefore, general and specific threat processing operates in parallel in early perception, with the ventral visual pathway engaged in specific processing of discrete threats and the dorsal visual pathway in general threat processing. Furthermore, selectively tuned to distinctive spatial-frequency channels and visual pathways, these parallel processes underpin dimensional and categorical threat characterization, promoting efficient threat response. These findings thus lend support to hybrid models of emotion.

Adolescence is a time of increased risk for the onset of psychological disorders associated with deficits in face emotion labeling. We used functional magnetic resonance imaging (fMRI) to examine age-related differences in brain activation while adolescents and adults labeled the emotion on fearful, happy and angry faces of varying intensities [0% (i.e. neutral), 50%, 75%, 100%]. Adolescents and adults did not differ on accuracy to label emotions. In the superior temporal sulcus, ventrolateral prefrontal cortex and middle temporal gyrus, adults show an inverted-U-shaped response to increasing intensities of fearful faces and a U-shaped response to increasing intensities of happy faces, whereas adolescents show the opposite patterns. In addition, adults, but not adolescents, show greater inferior occipital gyrus activation to negative (angry, fearful) vs positive (happy) emotions. In sum, when subjects classify subtly varying facial emotions, developmental differences manifest in several 'ventral stream' brain regions. Charting the typical developmental course of the brain mechanisms of socioemotional processes, such as facial emotion labeling, is an important focus for developmental psychopathology research.

Cheng, Rolls et al. examine whole-brain voxel-based resting-state functional connectivity in 418 people with autism. They reveal reduced connectivity between regions involved in facial expression processing and theory of mind (middle temporal gyrus), emotion processing (ventromedial prefrontal cortex), and the representation of self (precuneus and related posterior cingulate areas)., Whole-brain voxel-based unbiased resting state functional connectivity was analysed in 418 subjects with autism and 509 matched typically developing individuals. We identified a key system in the middle temporal gyrus/superior temporal sulcus region that has reduced cortical functional connectivity (and increased with the medial thalamus), which is implicated in face expression processing involved in social behaviour. This system has reduced functional connectivity with the ventromedial prefrontal cortex, which is implicated in emotion and social communication. The middle temporal gyrus system is also implicated in theory of mind processing. We also identified in autism a second key system in the precuneus/superior parietal lobule region with reduced functional connectivity, which is implicated in spatial functions including of oneself, and of the spatial environment. It is proposed that these two types of functionality, face expression-related, and of one’s self and the environment, are important components of the computations involved in theory of mind, whether of oneself or of others, and that reduced connectivity within and between these regions may make a major contribution to the symptoms of autism.

Implicit or automatic detection of social signals, which discriminate animate, intentional objects in the environment, is essential for higher social cognition and its development. Using functional magnetic resonance imaging, we identified the neural substrate of detecting simple visual social signals and examined its functional link with the mechanism of inferring another’s mental state. Healthy participants were presented with the eye-gaze shift (EG) and self-propelling motion (SP) under both implicit and explicit task conditions. They also performed a social role-playing game in which mental inference (MI) was implicitly prompted during the presentation of faces (implicit MI). Implicit detection of EG and SP activated the posterior middle temporal gyrus (pMTG) bilaterally, whereas the right posterior superior temporal sulcus was activated during the explicit conditions. We revealed that the individual variation in neural response in the right pMTG during implicit eye-gaze detection explains the individual tendency to recruit the regions implicated in mental-state inference (medial prefrontal cortex, temporal pole and striatum) during the implicit MI task. Our results suggest that the implicit detection of visual social signals involves the pMTG and underlies the development of higher social cognition.

The brain network underlying speech comprehension is usually described as encompassing fronto–temporal–parietal regions while neuroimaging studies of speech intelligibility have focused on a more spatially restricted network dominated by the superior temporal cortex. Here we use functional magnetic resonance imaging with a novel whole-brain multivariate pattern analysis (MVPA) to more fully characterize neural responses and connectivity to intelligible speech. Consistent with previous univariate findings, intelligible speech elicited greater activity in bilateral superior temporal cortex relative to unintelligible speech. However, MVPA identified a more extensive network that discriminated between intelligible and unintelligible speech, including left-hemisphere middle temporal gyrus, angular gyrus, inferior temporal cortex, and inferior frontal gyrus pars triangularis. These fronto–temporal–parietal areas also showed greater functional connectivity during intelligible, compared with unintelligible, speech. Our results suggest that speech intelligibly is encoded by distinct fine-grained spatial representations and within-task connectivity, rather than differential engagement or disengagement of brain regions, and they provide a more complete view of the brain network serving speech comprehension. Our findings bridge a divide between neural models of speech comprehension and the neuroimaging literature on speech intelligibility, and suggest that speech intelligibility relies on differential multivariate response and connectivity patterns in Wernicke's, Broca's, and Geschwind's areas.

Deficits in the connectivity between brain regions have been suggested to play a major role in the pathophysiology of schizophrenia. A functional magnetic resonance imaging (fMRI) analysis of schizophrenia was implemented using independent component analysis (ICA) to identify multiple temporally cohesive, spatially distributed regions of brain activity that represent functionally connected networks. We hypothesized that functional connectivity differences would be seen in auditory networks comprised of regions such as superior temporal gyrus as well as executive networks that consisted of frontal-parietal areas. Eight networks were found to be implicated in schizophrenia during the auditory oddball paradigm. These included a bilateral temporal network containing the superior and middle temporal gyrus; a default-mode network comprised of the posterior cingulate, precuneus, and middle frontal gyrus; and multiple dorsal lateral prefrontal cortex networks that constituted various levels of between-group differences. Highly task-related sensory networks were also found. These results indicate that patients with schizophrenia show functional connectivity differences in networks related to auditory processing, executive control, and baseline functional activity. Overall, these findings support the idea that the cognitive deficits associated with schizophrenia are widespread and that a functional connectivity approach can help elucidate the neural correlates of this disorder.

Introduction: Auditory hallucinations or voices are experienced by 75% of people diagnosed with schizophrenia. We presumed that auditory cortex of schizophrenia patients who experience hallucinations is tonically “tuned” to internal auditory channels, at the cost of processing external sounds, both speech and nonspeech. Accordingly, we predicted that patients who hallucinate would show less auditory cortical activation to external acoustic stimuli than patients who did not. Methods: At 9 Functional Imaging Biomedical Informatics Research Network (FBIRN) sites, whole-brain images from 106 patients and 111 healthy comparison subjects were collected while subjects performed an auditory target detection task. Data were processed with the FBIRN processing stream. A region of interest analysis extracted activation values from primary (BA41) and secondary auditory cortex (BA42), auditory association cortex (BA22), and middle temporal gyrus (BA21). Patients were sorted into hallucinators (n = 66) and nonhallucinators (n = 40) based on symptom ratings done during the previous week. Results: Hallucinators had less activation to probe tones in left primary auditory cortex (BA41) than nonhallucinators. This effect was not seen on the right. Discussion: Although “voices” are the anticipated sensory experience, it appears that even primary auditory cortex is “turned on” and “tuned in” to process internal acoustic information at the cost of processing external sounds. Although this study was not designed to probe cortical competition for auditory resources, we were able to take advantage of the data and find significant effects, perhaps because of the power afforded by such a large sample.