Investigation of the neural correlates of mentalizing through the Dynamic Inference Task, a new naturalistic task of social cognition.

Understanding others' intentions requires both the identification of social cues (e.g., emotional facial expressions, gaze direction) and the attribution of a mental state to another. The neural substrates of these processes have often been studied separately, and results are heterogeneous, in part attributable to the variety of paradigms used. The aim of the present study was to explore the neural regions underlying these sociocognitive processes, using a novel naturalistic task in which participants engage with human protagonists featured in videos. A total of 51 right-handed volunteers underwent functional magnetic resonance imaging while performing the Dynamic Inference Task (DIT), manipulating the degree of inference (high vs. low), the presence of emotion (emotional vs. nonemotional), and gaze direction (direct vs. averted). High nonemotional inference elicited neural activation in temporal regions encompassing the right posterior superior temporal sulcus. The presence (vs. absence) of emotion in the high-inference condition elicited a bilateral pattern of activation in internal temporal areas around the amygdala and orbitofrontal structures, as well as activation in the right dorsomedial part of the superior frontal gyrus and the left precuneus. On account of its dynamic, naturalistic approach, the DIT seems a suitable task for exploring social interactions and the way we interact with others, both in nonclinical and clinical populations.

Role of implicit learning abilities in metaphor understanding.

Although the use of metaphors is a central component of language, the processes that sustain their comprehension have yet to be specified. Work in the fields of both metaphors and implicit learning suggests that implicit learning abilities facilitate the comprehension of metaphors. However, to date, no study has directly explored the relationships between the understanding of metaphors and so-called implicit learning tasks. We used a meaning decision task comparing literal, metaphorical and meaningless expressions to assess metaphor understanding and a probabilistic serial reaction time task for assessing implicit learning. Our results show that implicit learning positively predicts the time gap between responses to literal and metaphorical expressions and negatively predicts the difference between metaphorical and meaningless expressions. Thus, when confronted with novel metaphors, participants with higher implicit learning abilities are better able to identify that the expressions have some meaning. These results are interpreted in the context of metaphor understanding and psycholinguistic theories.

Impact of hypomanic personality traits on brain functional connectivity during a dynamic theory-of-mind task.

Hypomanic personality traits are present in the general population and represent a risk factor for developing bipolar disorder. This personality style, notably its social component, is linked to difficulties in theory of mind (i.e., ability to infer mental states). Exploring the neural correlates of mental states' inference in individuals with these personality traits can provide meaningful insights into the development of bipolar disorder. The aim of the present study was therefore to investigate the potential impact of hypomanic traits on brain activation and task-based connectivity strength during a dynamic theory of mind task in a nonclinical population. A total of 52 nonclinical participants were recruited, and hypomanic traits were assessed with the Hypomanic Personality Scale. The severity of hypomanic traits was positively associated with right middle and inferior frontal gyri activations (in high vs. low inference in nonemotional condition and emotion vs. no emotion in high inference, respectively). It was also associated with stronger connectivity between the salience network (i.e., bilateral putamen and pallidum) and bilateral superior temporal gyri (high inference in nonemotional condition), and between cerebellar and temporal areas (high inference in emotional condition). These changes may either reflect adaptations or differential processing, and further studies are therefore mandatory.

Activation of the left medial temporal gyrus and adjacent brain areas during affective theory of mind processing correlates with trait schizotypy in a nonclinical population.

Schizophrenia, a severe psychiatric disorder, is associated with abnormal brain activation during theory of mind (ToM) processing. Researchers recently suggested that there is a continuum running from subclinical schizotypal personality traits to fully expressed schizophrenia symptoms. Nevertheless, it remains unclear whether schizotypal personality traits in a nonclinical population are associated with atypical brain activation during ToM tasks. Our aim was to investigate correlations between fMRI brain activation during affective ToM (ToMA) and cognitive ToM (ToMC) tasks and scores on the Schizotypal Personality Questionnaire (SPQ) and the Basic Empathy Scale in 39 healthy individuals. The total SPQ score positively correlated with brain activation during ToMA processing in clusters extending from the left medial temporal gyrus (MTG), lingual gyrus and fusiform gyrus to the parahippocampal gyrus (Brodmann area: 19). During ToMA processing, the right inferior occipital gyrus, right MTG, precuneus and posterior cingulate cortex negatively correlated with the emotional disconnection subscore and the total score of self-reported empathy. These posterior brain regions are known to be involved in memory and language, as well as in creative reasoning, in nonclinical individuals. Our findings highlight changes in brain processing associated with trait schizotypy in nonclinical individuals during ToMA but not ToMC processing.

Facial emotion recognition processes according to schizotypal personality traits: An eye-tracking study.

Facial emotion recognition has been shown to be impaired among patients with schizophrenia and, to a lesser extent, among individuals with high levels of schizotypal personality traits. However, aspects of gaze behavior during facial emotion recognition among the latter are still unclear. This study therefore investigated the relations between eye movements and facial emotion recognition among nonclinical individuals with schizotypal personality traits. A total of 83 nonclinical participants completed the Schizotypal Personality Questionnaire (SPQ) and performed a facial emotion recognition task. Their gaze behavior was recorded by an eye-tracker. Self-report questionnaires measuring anxiety, depressive symptoms, and alexithymia were administered. At the behavioral level, correlation analyses showed that higher SPQ scores were associated with lower surprise recognition accuracy scores. Eye-tracking data revealed that higher SPQ scores were associated with shorter dwell time on relevant facial features during sadness recognition. Regression analyses revealed that the total SPQ score was the only significant predictor of eye movements during sadness recognition, and depressive symptoms were the only significant predictor of surprise recognition accuracy. Furthermore, dwell time predicted response times for sadness recognition in that shorter dwell time on relevant facial features was associated with longer response times. Schizotypal traits may be associated with decreased attentional engagement in relevant facial features during sadness recognition and impede participants' response times. Slower processing and altered gaze patterns during the processing of sad faces could lead to difficulties in everyday social situations in which information must be rapidly processed to enable the successful interpretation of other people's behavior.

Neural correlates of semantic ambiguity resolution in paucisymptomatic bipolar disorder patients.

In addition to symptoms specifically related to mood dysregulation, patients with bipolar disorder (BD) show frequent alterations in formal thought organization. A disruption in semantic processing, notably in semantic inhibition, is one of the possible mechanisms that might explain this modified organization. However, to date, little is known about these mechanisms and their underlying neural substrates. This study aimed to identify the neural correlates of the semantic inhibition process in BD patients in comparison to healthy controls. Seventeen BD patients and 17 matched controls were recruited and underwent a 3T MRI scan. A semantic ambiguity resolution task was used during the scan to explore semantic inhibition. Whole-brain analyses were conducted on 13 BD patients and 16 controls. When compared to controls, BD patients had stronger activation in the bilateral temporal areas and right middle frontal gyrus, and less activation in the right hippocampus, parahippocampal area, and bilateral precunei. The present study revealed an altered fronto-temporo-parietal semantic inhibition network in BD patients that could reflect compensative mechanisms or modified semantic processing inducing abnormal thought organization, which has a major impact on the occupational and social functioning of the BD population.

Neural Correlates of Semantic Inhibition in Relation to Hypomanic Traits: An fMRI Study.

OBJECTIVES: Language modifications are a core feature of mania, but little is known about the semantic mechanisms behind these disturbances. The aim of the present study was thus to identify deficits in semantic inhibition and their respective neural activation patterns in a sample of individuals assessed for hypomanic personality traits. METHODS: Thirty-six young adults with no neurological or psychiatric diagnoses were assessed for hypomanic personality traits with the Hypomanic Personality Scale (HPS) and underwent an fMRI task of semantic ambiguity resolution. RESULTS: Regression analyses revealed a positive association between the HPS score and activity in the left superior frontal gyrus, left inferior parietal lobule, and anterior cingulate gyrus during semantic ambiguity resolution. CONCLUSION: We found a link between HPS scores and brain areas that are part of the cognitive control loop and semantic memory network during language processing in a nonclinical sample of individuals. The hyperactivation of these regions may reflect a compensatory neural response in a population with greater vulnerability to BD.

Neural Correlates of Contrast and Humor: Processing Common Features of Verbal Irony.

Irony is a kind of figurative language used by a speaker to say something that contrasts with the context and, to some extent, lends humor to a situation. However, little is known about the brain regions that specifically support the processing of these two common features of irony. The present study had two main aims: (i) investigate the neural basis of irony processing, by delivering short ironic spoken sentences (and their literal counterparts) to participants undergoing fMRI; and (ii) assess the neural effect of two irony parameters, obtained from normative studies: degree of contrast and humor appreciation. Results revealed activation of the bilateral inferior frontal gyrus (IFG), posterior part of the left superior temporal gyrus, medial frontal cortex, and left caudate during irony processing, suggesting the involvement of both semantic and theory-of-mind networks. Parametric models showed that contrast was specifically associated with the activation of bilateral frontal and subcortical areas, and that these regions were also sensitive to humor, as shown by a conjunction analysis. Activation of the bilateral IFG is consistent with the literature on humor processing, and reflects incongruity detection/resolution processes. Moreover, the activation of subcortical structures can be related to the reward processing of social events.

Differential bilateral involvement of the parietal gyrus during predicative metaphor processing: an auditory fMRI study.

Despite the growing literature on figurative language processing, there is still debate as to which cognitive processes and neural bases are involved. Furthermore, most studies have focused on nominal metaphor processing without any context, and very few have used auditory presentation. We therefore investigated the neural bases of the comprehension of predicative metaphors presented in a brief context, in an auditory, ecological way. The comprehension of their literal counterparts served as a control condition. We also investigated the link between working memory and verbal skills and regional activation. Comparisons of metaphorical and literal conditions revealed bilateral activation of parietal areas including the left angular (lAG) and right inferior parietal gyri (rIPG) and right precuneus. Only verbal skills were associated with lAG (but not rIPG) activation. These results indicated that predicative metaphor comprehension share common activations with other metaphors. Furthermore, individual verbal skills could have an impact on figurative language processing.