Empathy and aversion: the neural signature of mentalizing in Tourette syndrome

Theory of mind in neurodevelopmental disorders: beyond autistic spectrum disorder

INTRODUCTION

Theory of mind (ToM) is the human ability to perceive, interpret, and attribute the mental states of other people, and the alteration of this cognitive function is a core symptom of autistic spectrum disorder (ASD). In such other neurodevelopmental disorders as childhood-onset obsessive-compulsive disorder (OCD) and Tourette syndrome (TS) that can present with cognitive dysfunctions, ToM has been less extensively studied, especially in the young population. The aim of the study was to compare advanced ToM between groups of young people diagnosed with OCD, TS, or ASD and a control group.

METHODS

Clinical interviews were conducted with male patients aged between 11 and 17 years with a main diagnosis of OCD (n = 19), TS (n = 14), or ASD (n = 18), and a control group (n = 20). We administered instruments for estimating intelligence quotient and severity of psychiatric symptoms, and tasks to evaluate ToM (the "Stories from everyday life" task and the "Reading the mind in the eyes" test).

RESULTS

Young people with TS and with ASD present similar difficulties in solving advanced ToM tasks, whereas patients with childhood-onset OCD present similar results to controls.

CONCLUSIONS

ToM is altered in other neurodevelopmental disorders beyond ASD, such as TS.

A scoping review of oral language and social communication abilities in children with Tourette syndrome

BACKGROUND

Children with Tourette syndrome (TS) have historically experienced problems in academic and social settings, yet their language and communication abilities have not been extensively researched.

AIMS

This scoping review maps the literature on the oral language and social communication abilities of children with TS in order to describe the nature of the current literature, present a summary of major findings and identify where gaps exist.

METHODS

A scoping review was completed to identify studies measuring the oral language or social communication abilities of children with TS. A systematic search of six electronic databases was conducted to obtain published and unpublished literature. All English studies measuring the oral language or social communication abilities of children with TS were included. Information was extracted from records and knowledge was synthesised in a narrative summary.

MAIN CONTRIBUTION

We identified 56 records for inclusion. Almost all records were located in journals within the fields of psychology and psychiatry. Skills most often studied were verbal IQ and verbal fluency. The literature suggests an increased prevalence of language disorders and social communication problems in children with TS; however, literature comprehensively detailing these challenges was scarce. Language strengths were identified in verbal intelligence, story/sentence recall, categorisation and performance on tasks at the single-word level.

CONCLUSIONS

Oral language and social communication skills are important for academic and social success. This review brings scattered literature together to provide up-to-date information about language in children with TS and highlights that there are considerable gaps in our knowledge about language and communication in this population. This scoping review can inform future research and support speech language pathologists in the assessment of young people with TS.

WHAT THIS PAPER ADDS

What is already known on the subject Speech-language pathologists (SLPs) working in various contexts (e.g., schools, mental health teams) are likely to encounter children with Tourette syndrome (TS); however, the description of this population and potential communication characteristics is not well represented in the SLP literature. Previous literature reviews have reported strengths in verbal fluency and morphological processing. Challenges in expressive language, higher order language, social cognition and a propensity towards autistic traits have also been identified. What this paper adds to existing knowledge This review differs from previous narrative reviews by employing a systematic approach to searching for literature. As a result, we identified 25 additional studies that had not been cited in previous reviews and additional relevant findings in 23 previously reviewed studies. This review confirms several previous conclusions about language in children with TS and extends or clarifies several others, thereby providing the most current information on oral language and social communication abilities. The use of current taxonomies of language and social communication helps to organise this literature for clinicians and researchers in speech-language pathology and identifies a need for further research from the SLP perspective. What are the potential or actual clinical implications of this work? These results imply that SLPs should screen children with TS for language disorders and investigate social communication and social interaction development. Clinicians can expect greater challenges in language and communication development for children with complex forms of TS (i.e., those who exhibit co-occurring conditions such as attention-deficit/hyperactivity disorder). The multidisciplinary nature of the current literature implies that clinical collaboration with other disciplines will be of particular benefit to serving this group of children.

Social cognition in hyperkinetic movement disorders: a systematic review

Numerous lines of research indicate that our social brain involves a network of cortical and subcortical brain regions that are responsible for sensing and controlling body movements. However, it remains unclear whether movement disorders have a systematic impact on social cognition. To address this question, we conducted a systematic review examining the influence of hyperkinetic movement disorders (including Huntington disease, Tourette syndrome, dystonia, and essential tremor) on social cognition. Following the PRISMA guidelines and registering the protocol in the PROSPERO database (CRD42022327459), we analyzed 50 published studies focusing on theory of mind (ToM), social perception, and empathy. The results from these studies provide evidence of impairments in ToM and social perception in all hyperkinetic movement disorders, particularly during the recognition of negative emotions. Additionally, individuals with Huntington's Disease and Tourette syndrome exhibit empathy disorders. These findings support the functional role of subcortical structures (such as the basal ganglia and cerebellum), which are primarily responsible for movement disorders, in deficits related to social cognition.

Neural, physiological and behavioural correlates of empathy for pain in Tourette syndrome

Persons with Tourette syndrome show altered social behaviours, such as echophenomena and increased personal distress in emotional situations. These symptoms may reflect an overactive mirror neuron system, causing both increased automatic imitation and a stronger tendency to share others' emotions. To test this, we measured the individual level of echophenomena with a video protocol and experimentally induced empathy for pain in 21 participants with Tourette syndrome and 25 matched controls. In the empathy for pain paradigm, pictures of hands and feet in painful or neutral situations were presented, while we measured participants' EEG and skin conductance response. Changes in somatosensory mu suppression during the observation of the pictures and pain ratings were compared between groups, and correlations were calculated with the occurrence of echophenomena, self-reported empathy and clinical measures. Our Tourette syndrome sample showed significantly more echophenomena than controls, but the groups showed no behavioural differences in empathic abilities. However, controls, but not patients with Tourette syndrome, showed the predicted increased mu suppression when watching painful compared to neutral actions. While echophenomena were present in all persons with Tourette syndrome, the hypothesis of an overactive mirror neuron system in Tourette syndrome could not be substantiated. On the contrary, the Tourette syndrome group showed a noticeable lack of mu attenuation in response to pain stimuli. In conclusion, we found a first hint of altered processing of others' emotional states in a brain region associated with the mirror neuron system.

The non-human animal reading the mind in the eyes test (NARMET): A new measure for the assessment of social cognition

The Reading the Mind in the Eyes test (RMET) is a widely applied test of social cognition, based on mental state judgments in response to photographs of human eyes, which can elicit impairment in patients with numerous psychiatric and neurological disorders. However, interpretation of task performance is limited without the use of appropriate control tasks. In addition to a matched task requiring age judgments of the RMET stimuli, it was recently shown that a mental state judgment task of comparable difficulty, could be developed using photographs of domestic cat eyes. The current study aimed to further develop a Non-human Animal RMET (NARMET) by testing additional stimuli in the form of photographs of domestic dog eyes. A variety of additional tasks were used alongside the eyes test stimuli in a large sample of healthy young adults, to explore how alexithymia, schizotypal features, and autistic tendencies may differentially influence mental state attribution in response to cat, dog, and human eyes test stimuli. The resulting NARMET features both cat and dog trials, depicting a similar range of complex mental states to the human RMET. It shows favorable psychometric properties as well as being well matched to the RMET in terms of linguistic variables, length and difficulty. However, reading measures predicted performance on the RMET, but not on the NARMET. Although further testing is required in samples with a higher proportion of males, future application of the NARMET in neuropsychiatric populations exhibiting cognitive and behavioral difficulties could offer enhanced assessment of social cognitive skills.

Die Bedeutung des Vorgefühls bei Tic-Störungen

Zusammenfassung. Theoretischer Hintergrund: Die Funktion des Vorgefühls in der Pathogenese und Aufrechterhaltung von Tic-Störungen (TS) wird in den letzten Jahren verstärkt erforscht. Die mögliche funktionelle Bedeutung der Vorgefühle wird aber noch nicht ausreichend verstanden. Methode: Im vorliegenden Review wird der Kenntnisstand zu Vorgefühlen entlang eines integrativen funktionalen Störungsmodells zusammengefasst. Ergebnisse: Im Vergleich zum Jugendalter nehmen Tic-Symptome bei Tic-Störungen im Erwachsenenalter ab, während immer mehr Betroffene ein Vorgefühl berichten. Hierbei kann zwischen einem allgemeinen Vorgefühl (trait) und dem Drang, Tics auszuführen (state) unterschieden werden. Das Vorgefühl als trait ist abhängig von der Interozeptionsfähigkeit. An den Drang, Tics auszuführen, kann habituiert werden, moderiert von Aufmerksamkeits- und Attributionsprozessen. Durch das Auflösen des Vorgefühl-Tic-Reizreaktionsmusters reduzieren sich die Tic-Symptome. Schlussfolgerung: Für weitere Erkenntnisse in Bezug auf die Bedeutung von Vorgefühl und den Drang, Tics auszuführen, sollten zukünftige Forschungsansätze Drang und allgemeine Vorgefühle in therapeutischen Interventionsstudien berücksichtigen, weitere Interozeptionsparadigmen einbeziehen und die Entwicklung von allgemeinem Vorgefühl und Drang über die Lebensspanne hinweg untersuchen.

The Transdiagnostic Relevance of Self-Other Distinction to Psychiatry Spans Emotional, Cognitive and Motor Domains

Self-other distinction refers to the ability to distinguish between our own and other people's physical and mental states (actions, perceptions, emotions etc.). Both the right temporo-parietal junction and brain areas associated with the human mirror neuron system are likely to critically influence self-other distinction, given their respective contributions to theory of mind and embodied empathy. The degree of appropriate self-other distinction will vary according to the exact social situation, and how helpful it is to feel into, or remain detached from, another person's mental state. Indeed, the emotional resonance that we can share with others affords the gift of empathy, but over-sharing may pose a downside, leading to a range of difficulties from personal distress to paranoia, and perhaps even motor tics and compulsions. The aim of this perspective paper is to consider how evidence from behavioral and neurophysiological studies supports a role for problems with self-other distinction in a range of psychiatric symptoms spanning the emotional, cognitive and motor domains. The various signs and symptoms associated with problematic self-other distinction comprise both maladaptive and adaptive (compensatory) responses to dysfunction within a common underlying neuropsychological mechanism, compelling the adoption of more holistic transdiagnostic therapeutic approaches within Psychiatry.

Emotion regulation and tic disorders in children

Tic disorders (TD) are developmental neuropsychiatric conditions often accompanied by comorbid conditions, and psychosocial hardships for child and family. The etiology of tics is unknown, and is complex and multifactorial. Stress is known to aggravate tic expression as well as associated comorbidities. Consequently, this study focused on possible connections between stress, emotion regulation, tic expression, and related psychopathology. Sixty consecutive admissions were assessed for perceived stress, emotional dysregulation, severity of obsessions and compulsions, anxiety, depression, attention deficit disorder, and tic expression at a TD clinic, in a university affiliated pediatric hospital. The results indicated that stress and emotion dysregulation were significantly related to both tic expression and severity of comorbidities. We discuss the role of emotion regulation dimensions regarding TD and related psychopathology as well as the mediating role of emotion regulation, and how they may contribute to the development of improved therapies for children with TD.

Microstructural Abnormalities of White Matter Across Tourette Syndrome: A Voxel-Based Meta-Analysis of Fractional Anisotropy

Introduction: Tourette syndrome (TS) is a neuropsychiatric disorder with multiple motor and vocal tics whose neural basis remains unclear. Diffusion tensor imaging (DTI) studies have demonstrated white matter microstructural alternations in TS, but the findings are inconclusive. In this study, we aimed to elucidate the most consistent white matter deficits in patients with TS.

Method: By systematically searching online databases up to December 2020 for all DTI studies comparing fractional anisotropy (FA) between patients with TS and healthy controls (HCs), we conducted anisotropic effect size-signed differential mapping (AES-SDM) meta-analysis to investigate FA differences in TS, as well as performed meta-regression analysis to explore the effects of demographics and clinical characteristics on white matter abnormalities among TS.

Results: A total of eight datasets including 168 patients with TS and 163 HCs were identified. We found that TS patients showed robustly decreased FA in the corpus callosum (CC) and right inferior longitudinal fasciculus (ILF) compared with HCs. These two regions preserved significance in the sensitivity analysis. No regions of increased FA were reported. Meta-regression analysis revealed that age, sex, tic severity, or illness duration of patients with TS were not linearly correlated with decreased FA.

Conclusion: Patients with TS display deficits of white matter microstructure in the CC and right ILF known to be important for interhemispheric connections as well as long association fiber bundles within one hemisphere. Because the results reported in the primary literature were highly variable, future investigations with large samples would be required to support the identified white matter changes in TS.

Theory of mind in neurodevelopmental disorders: Beyond autistic spectrum disorder

INTRODUCTION

Theory of mind (ToM) is the human ability to perceive, interpret, and attribute the mental states of other people, and the alteration of this cognitive function is a core symptom of autistic spectrum disorder (ASD). In such other neurodevelopmental disorders as childhood-onset obsessive-compulsive disorder (OCD) and Tourette syndrome (TS) that can present with cognitive dysfunctions, ToM has been less extensively studied, especially in the young population. The aim of the study was to compare advanced ToM between groups of young people diagnosed with OCD, TS, or ASD and a control group.

METHODS

Clinical interviews were conducted with male patients aged between 11 and 17 years with a main diagnosis of OCD (n=19), TS (n=14), or ASD (n=18), and a control group (n=20). We administered instruments for estimating intelligence quotient and severity of psychiatric symptoms, and tasks to evaluate ToM (the "Stories from everyday life" task and the "Reading the mind in the eyes" test).

RESULTS

Young people with TS and with ASD present similar difficulties in solving advanced ToM tasks, whereas patients with childhood-onset OCD present similar results to controls.

CONCLUSIONS

ToM is altered in other neurodevelopmental disorders beyond ASD, such as TS.

Swearing and coprophenomena - A multidimensional approach

Swearing, cursing, expletives - all these terms are used to describe the utterance of taboo words. Studies show that swearing makes up around 0.5 % of the daily spoken content, however, the inter-individual variability is very high. One kind of pathologic swearing is coprolalia in Tourette syndrome (TS), which describes the involuntary outburst of taboo words. Coprolalia occurs in approximately 20-30 % of all patients with TS. This review compares swearing in healthy people and coprolalia in people with TS and is the first one to develop a multidimensional framework to account for both phenomena from a similar perspective. Different research findings are embedded in one theoretical framework consisting of reasons, targets, functions/effects and influencing factors for swearing and coprolalia. Furthermore, the very limited research investigating obscene gestures and copropraxia, compulsive obscene gestures, is summarized. New research questions and gaps are brought up for swearing, obscene gestures and coprophenomena.

Automatic imitation in youngsters with Gilles de la Tourette syndrome: A behavioral study

It is widely known that humans have a tendency to imitate each other and that appropriate modulation of automatic imitative behaviors has a crucial function in social interactions. Gilles de la Tourette syndrome (GTS) is a childhood-onset neuropsychiatric disorder characterized by motor and phonic tics. Apart from tics, patients with GTS are often reported to show an abnormal tendency to automatically imitate others' behaviors (i.e., echophenomena), which may be related to a failure in top-down inhibition of imitative response tendencies. The aim of the current study is to explore the top-down inhibitory mechanisms on automatic imitative behaviors in youngsters with GTS. Error rates and reaction times from 32 participants with GTS and 32 controls were collected in response to an automatic imitation task assessing the influence of observed movements displayed in the first-person perspective on congruent and incongruent motor responses. Results showed that participants with GTS had higher error rates than controls, and their responses were faster than those of controls in incompatible stimuli. Our findings provide novel evidence of a key difference between youngsters with GTS and typically developing participants in the ability to effectively control the production of own motor responses to sensory inputs deriving from observed actions.

Predictors of performance on the Reading the Mind in the Eyes Test

We explored factors associated with performance on the Reading the Mind in the Eyes Test (RMET). 180 undergraduate students completed the human RMET requiring forced-choice mental state judgment; a control human Age Eyes Test (AET) requiring age judgment; a Cat Eyes Test (CET) requiring mental state judgment; and measures of executive function, empathy and psychopathology. Versions of the CET and AET were created that matched the RMET for difficulty (accuracy 71%). RMET and CET performance were strongly correlated after accounting for AET performance. Working memory, schizotypal personality and empathy predicted RMET accuracy but not CET scores. Liking dogs predicted higher accuracy on all eyes tasks, whereas liking cats predicted greater mentalizing but reduced emotional expression. Importantly, we replicated our core findings relating to accuracy and correlations between the CET and RMET in a second sample of 228 students. In conclusion, people can apply similar skills when interpreting cat and human expressions. As RMET and CET performance were found to be differentially affected by executive function and psychopathology, the use of social cognitive measures featuring non-human animals may be of particular use in future clinical research.

The cognitive neuropsychiatry of Tourette syndrome

Introduction: Converging evidence from both clinical and experimental studies has shown that Tourette syndrome (TS) is not a unitary condition, but a cluster of multiple phenotypes, which encompass both tics and specific behavioural and cognitive symptoms (mainly attention-deficit and hyperactivity disorder and obsessive-compulsive disorder). Methods: We conducted a narrative review of the recent literature on the cognitive neuropsychiatry of TS. Results: Although clinical research has shown that TS is not associated with cognitive deficits per se, the findings of recent studies have suggested the presence of subtle alterations in specific cognitive functions. A promising line of research on imitative behaviour could provide a common background for the alterations in executive control and social cognition observed in TS. Two different (but not mutually exclusive) neurocognitive theories have recently suggested that TS could originate from altered perception-action binding and social decision-making dysfunction, respectively. Conclusions: Since the presence of behavioural comorbidities influences individualised treatment approaches, it is likely that a more precise characterisation of TS phenotypes, including cognitive aspects, will result in improved levels of care for patients with tic disorders.

Social Cognition in Gilles de la Tourette Syndrome

Abstract. Research on the neural mechanisms underlying Gilles de la Tourette syndrome (GTS) has mostly concentrated on abnormalities in basal ganglia circuits. Recent alternative accounts, however, focused more on social and affective aspects. Individuals with GTS show peculiarities in their social and affective domain, including echophenomena, coprolalia, and nonobscene socially inappropriate behavior. This article reviews the experimental and theoretical work done on the social symptoms of GTS. We discuss the role of different social cognitive and affective functions and associated brain networks, namely, the social-decision-making system, theory-of-mind functions, and the so-called “mirror-neuron” system. Although GTS affects social interactions in many ways, and although the syndrome includes aberrant social behavior, the underlying cognitive, affective, and neural processes remain to be investigated.

The Association of Non-obscene Socially Inappropriate Behavior With Attention-Deficit/Hyperactivity Disorder Symptoms, Conduct Problems, and Risky Decision Making in a Large Sample of Adolescents

Non-obscene socially inappropriate behavior (NOSI) is recognized as part of the tic disorder spectrum but has received little attention from researchers to date. A study in 87 patients with Tourette syndrome showed that comorbid attention-deficit/hyperactivity disorder (ADHD) and conduct disorder were also associated with an increase in socially inappropriate behavior. This study used data from the Millennium Cohort Study to investigate the relationship between NOSI and emotional symptoms, conduct problems, and hyperactivity/inattention as assessed by the Strengths and Difficulties Questionnaire (SDQ) in 1,280 youths, aged 14 years. Furthermore, the relationship between NOSI and decision-making processes as assessed by the Cambridge Gambling Task (CGT) was investigated. Hyperactivity/inattention and conduct problems were significantly associated with NOSI; emotional problems were not. Risk taking was significantly associated with misbehaving in lessons but not with being rude or noisy in public. The results replicate and confirm the association of NOSI with ADHD and conduct problems in a large sample, although it should be stressed that the size of the association was small. The results also suggest that some inappropriate behaviors are related to risk-taking behavior, while others are not.

What Do You Have in Mind? Measures to Assess Mental State Reasoning in Neuropsychiatric Populations

Social interaction is closely associated with both functional capacity and well-being. Previous research has not only revealed evidence of social dysfunction in individuals with a wide range of psychiatric and neurological disorders but also generated an abundance of potential measures for assessing social cognition. This review explores the most popular measures used within neuropsychiatric populations to investigate the ability to recognize or reason about the mental states of others. Measures are also critically analyzed in terms of strengths and limitations to aid task selection in future clinical studies. The most frequently applied assessment tools use verbal, visual or audiovisual forms of presentation and assess recognition of mental states from facial features, self-rated empathy, the understanding of other's cognitive mental states such as beliefs and intentions, or the ability to combine knowledge of other's thoughts and emotions in order to understand subtle communications or socially inappropriate behavior. Key weaknesses of previous research include limited investigation of relationships with clinical symptoms, and underutilization of measures of everyday social functioning that offer a useful counterpart to traditional "lab" tasks. Future studies should aim to carefully select measures not only based on the range of skills to be assessed but also taking into account potential difficulties with interpretation and the need to gain insight into the application of social cognitive skills as well as ability per se. Some of the best measures include those with well-matched control trials (e.g., Yoni Task) or those that restrict the influence of verbal deficits (e.g., intentions comic strip task), elicit spontaneous mentalizing (e.g., Animations Task), and possess greater ecological validity (e.g., Movie for the Assessment of Social Cognition). Social cognitive research within psychiatric populations will be further enhanced through the development of more closely matched control tasks, and the exploration of relationships between task performance, medication, strategy use, and broader emotional and motor functions.

Alexithymia and tic disorders: a study on a sample of children and their mothers

Tic disorders are neurodevelopmental disorders characterised by the presence of motor or phonic tics, or both. Patients with tic disorders commonly report premonitory urges of tics. Alexithymia is a psychological trait characterised by a difficulty in identifying and expressing one's own feelings and by an externally oriented thinking. We aimed to explore alexithymia in children with tic disorders and in their mothers. Global alexithymia scores of both children with tic disorders and of their mothers did not differ from those of the participants from the control group. In the tic disorder group, however, both children and their mothers showed a cognitive style characterised by operational thinking and a lack of imaginative abilities. The mothers of children with tic disorder reported significantly higher parental stress. Alexithymia was not predictive of tic severity but was predictive of the severity of the premonitory urges. The implications of these findings are discussed.

Tourette Syndrome as a Disorder of the Social Decision Making Network

Tourette syndrome is a common neurodevelopmental disorder defined by the presence of tics, stereotyped involuntary movements and phonations. Considerable evidence points to developmental abnormalities of the basal ganglia as tic substrates. Basal ganglia dysfunction does not account for important features of Tourette syndrome, including its natural history, male predominance, and the characteristic quality and distribution of tics. The latter mainly involve eye, face, and head movements, in addition to a variety of simple to complex phonations. A major normal function of these movements, and of phonations as well, is social signaling. Many important species- and sex-specific stereotyped social behaviors are mediated by a phylogenetically conserved network of subcortical nuclei, the social behavior network (SBN). Some SBN nuclei are sexually dimorphic, and SBN function is modulated strongly by gonadal steroids. Recent studies indicate that the SBN meshes with the basal ganglia to form a larger network, the Social Decision Making Network (SDM; O'Connell and Hofmann [2011]). The SDM concept overlaps significantly with Holstege's (1993) model of an emotional motor system mediating socially relevant facial movements and phonations. Dopaminergic signaling within the basal ganglia component of the SDM may regulate social act motivation with the SBN component responsible for act expression. Developmental SDM abnormalities can explain all major Tourette syndrome features, including natural history, male predominance, the characteristic distribution of tics, and their stereotyped quality. Some data directly support this hypothesis. Tourette syndrome may be a disorder of social communication manifesting primarily as abnormal involuntary movements.

Reduced specificity of autobiographical memories in young people with tic disorders

OBJECTIVE

Depression is common in Tourette syndrome and Chronic Tic Disorders (TS/CTD) and contributes to significant impairment. The specificity of autobiographical memories is implicated in an individual's sense of self and their daily functioning but also in the onset and development of depression in the general population. Here, we examined whether memory specificity is reduced in young people with TS/CTD, relative to control participants, and whether memory specificity is associated with depression.

METHOD

Thirty young people with TS/CTD (14 females; age: x̅ = 11.31; SD = 1.66; 87% White British) and twenty-six (12 females; age: x̅ = 11.23; SD = 2.43; 77% White British) control participants completed the study. Participants completed the Autobiographical Memory Task, which asks participants to respond with a specific memory to cue words, and a questionnaire measure of depressive symptoms.

RESULTS

There was no significant difference between the two groups in terms of age, gender, ethnicity, IQ and depressive symptomatology. Young people with TS/CTD had less specific autobiographical memories than their peers (p < 0.001, r = 0.49). Across both groups, increased memory specificity for positive cue words was associated with reduced depressive symptomatology (p < 0.001, R² = 0.51).

CONCLUSIONS

Our findings indicate that autobiographical memory in young people with TS is characterised by a lack of specificity and, as with neurotypical peers, reduced memory specificity for positive words is associated with depressive symptoms. Autobiographical memory specificity could be an important factor in understanding mood symptoms that characterise young people with TS/CTD and may be an important cognitive target to reduce the development of depression in young people with TS/CTD.

Social cognition and self-other distinctions in neuropsychiatry: Insights from schizophrenia and Tourette syndrome

Impairments in social cognition may reflect dysfunction of disorder specific or disorder general mechanisms. Although cross-disorder comparison may prove insightful, few studies have compared social cognition in different neuropsychiatric disorders. Parallel investigation of schizophrenia and Tourette syndrome (TS) is encouraged by similarities including the presence of problematic social behavior, echophenomena, emotional dysregulation and dopamine dysfunction. Focusing on tests of social cognition administered in both disorders, this review aims to summarize behavioral, neurophysiological and neuroimaging findings, before exploring how these may contribute to clinical symptoms. Studies investigating social cognition (imitation, emotion recognition, and understanding of beliefs or intentions) in patients with schizophrenia or TS were identified through Web of Science and PubMed searches. Although findings indicate that social cognitive deficits are more apparent in schizophrenia, adults with TS can exhibit similar task performance to patients with paranoia. In both disorders, behavioral and neuroimaging findings raise the possibility of increased internal simulation of others' actions and emotions, in combination with a relative under-application of mentalizing. More specifically, dysfunction in neurobiological substrates such as temporo-parietal junction and inferior frontal gyrus may underlie problems with self-other distinctions in both schizophrenia and TS. Difficulties in distinguishing between actions and mental states linked to the self and other may contribute to a range of psychiatric symptoms, including emotional dysregulation, paranoia, social anhedonia and socially disruptive urges. Comparing different patient populations could therefore reveal common neuro-cognitive risk factors for the development of problematic social behaviors, in addition to markers of resilience, coping strategies and potential neuro-compensation mechanisms.

Through your eyes or mine? The neural correlates of mental state recognition in Huntington's disease

Huntington's disease (HD) can impair social cognition. This study investigated whether patients with HD exhibit neural differences to healthy controls when they are considering mental and physical states relating to the static expressions of human eyes. Thirty-two patients with HD and 28 age-matched controls were scanned with fMRI during two versions of the Reading the Mind in the Eyes Task: The standard version requiring mental state judgments, and a comparison version requiring judgments about age. HD was associated with behavioral deficits on only the mental state eyes task. Contrasting the two versions of the eyes task (mental state > age judgment) revealed hypoactivation within left middle frontal gyrus and supramarginal gyrus in HD. Subgroup analyses comparing premanifest HD patients to age-matched controls revealed reduced activity in right supramarginal gyrus and increased activity in anterior cingulate during mental state recognition in these patients, while manifest HD was associated with hypoactivity in left insula and left supramarginal gyrus. When controlling for the effects of healthy aging, manifest patients exhibited declining activation within areas including right temporal pole. Our findings provide compelling evidence for a selective impairment of internal emotional status when patients with HD appraise facial features in order to make social judgements. Differential activity in temporal and anterior cingulate cortices may suggest that poor emotion regulation and emotional egocentricity underlie impaired mental state recognition in premanifest patients, while more extensive mental state recognition impairments in manifest disease reflect dysfunction in neural substrates underlying executive functions, and the experience and interpretation of emotion.

Centrality of prefrontal and motor preparation cortices to Tourette Syndrome revealed by meta-analysis of task-based neuroimaging studies

Tourette Syndrome (TS) is a neurodevelopmental condition characterized by chronic multiple tics, which are experienced as compulsive and 'unwilled'. Patients with TS can differ markedly in the frequency, severity, and bodily distribution of tics. Moreover, there are high comorbidity rates with attention deficit hyperactivity disorder (ADHD), obsessive compulsive disorder (OCD), anxiety disorders, and depression. This complex clinical profile may account for apparent variability of findings across neuroimaging studies that connect neural function to cognitive and motor behavior in TS. Here we crystalized information from neuroimaging regarding the functional circuitry of TS, and furthermore, tested specifically for neural determinants of tic severity, by applying activation likelihood estimation (ALE) meta-analyses to neuroimaging (activation) studies of TS. Fourteen task-based studies (13 fMRI and one H2O-PET) met rigorous inclusion criteria. These studies, encompassing 25 experiments and 651 participants, tested for differences between TS participants and healthy controls across cognitive, motor, perceptual and somatosensory domains. Relative to controls, TS participants showed distributed differences in the activation of prefrontal (inferior, middle, and superior frontal gyri), anterior cingulate, and motor preparation cortices (lateral premotor cortex and supplementary motor area; SMA). Differences also extended into sensory (somatosensory cortex and the lingual gyrus; V4); and temporo-parietal association cortices (posterior superior temporal sulcus, supramarginal gyrus, and retrosplenial cortex). Within TS participants, tic severity (reported using the Yale Global Tic Severity Scale; YGTSS) selectively correlated with engagement of SMA, precentral gyrus, and middle frontal gyrus across tasks. The dispersed involvement of multiple cortical regions with differences in functional reactivity may account for heterogeneity in the symptomatic expression of TS and its comorbidities. More specifically for tics and tic severity, the findings reinforce previously proposed contributions of premotor and lateral prefrontal cortices to tic expression.

The psychometric properties of the "Reading the Mind in the Eyes" Test: an item response theory (IRT) analysis

INTRODUCTION

The "Reading the Mind in the Eyes" Test (hereafter: Eyes Test) is considered an advanced task of the Theory of Mind aimed at assessing the performance of the participant in perspective-takingthat is, the ability to sense or understand other people's cognitive and emotional states. In this study, the item response theory analysis was applied to the adult version of the Eyes Test.

METHODS

The Italian version of the Eyes Test was administered to 200 undergraduate students of both genders (males = 46%). Modified parallel analysis (MPA) was used to test unidimensionality. Marginal maximum likelihood estimation was used to fit the 1-, 2-, and 3-parameter logistic (PL) model to the data. Differential Item Functioning (DIF) due to gender was explored with five independent methods.

RESULTS

MPA provided evidence in favour of unidimensionality. The Rasch model (1-PL) was superior to the other two models in explaining participants' responses to the Eyes Test. There was no robust evidence of gender-related DIF in the Eyes Test, although some differences may exist for some items as a reflection of real differences by group.

CONCLUSIONS

The study results support a one-factor model of the Eyes Test. Performance on the Eyes Test is defined by the participant's ability in perspective-taking. Researchers should cease using arbitrarily selected subscores in assessing the performance of participants to the Eyes Test. Lack of gender-related DIF favours the use of the Eyes Test in the investigation of gender differences concerning empathy and social cognition.