Commentary on “Autism, oxytocin and interoception”: Alexithymia, not Autism Spectrum Disorders, is the consequence of interoceptive failure

Potential mechanisms underlying the association between feeding and eating disorders and autism

There is a reliable association between autism and Feeding and Eating Disorders. Concerningly, where these two conditions co-occur, clinical outcomes of Feeding and Eating Disorders are significantly worse, and treatment less effective, than when the Feeding and Eating Disorders occur in neurotypical individuals. Problematically, the reason for the association between autism and Feeding and Eating Disorders is poorly understood, which constrains advances in clinical care. This paper outlines several possible mechanisms that may underlie the observed association and suggests ways in which they may be empirically tested. Mechanisms are split into those producing an artefactual association, and those reflecting a genuine link between conditions. Artefactual associations may be due to conceptual overlap in both diagnostic criteria and measurement, Feeding and Eating Disorders causing transient autistic traits, or the association being non-specific in nature. A genuine association between autism and Feeding and Eating Disorders may be due to common causal factors, autism directly or indirectly causing Feeding and Eating Disorders, and Feeding and Eating Disorders being a female manifestation of autism.

The meaning of autistic movements

LAY ABSTRACT

What is already known?Moving the body in 'stereotyped', 'repetitive', 'ritualised' or 'unusual' ways is part of the criteria for receiving a diagnosis of autism. However, the reasons for these movements and their personal value are not well understood. Certain ways of moving have become part of a disorder, and have received negative judgements, whereas other movements have not.What this paper adds?We searched online blogs for descriptions of movement written by autistic adults, using their preferred language and definitions. The blog authors said that many types of movement attracted negative judgement, including mis-coordination shown during sports, dancing in unusual places or moving repetitively, such as when stimming. However, movement provided personal benefits, and could enhance thinking and focus, provide meaningful routine, contribute to sensory regulation, release energy, increase body awareness, emotion regulation and strengthen self-identity.Implications for practice and policyMovement could be a well-being resource, used to reduce distraction, overwhelm, confusion and distress for autistic people. This should be considered within personal coping strategies and psychological therapies. The examples provided in this study could inform autism assessments, to ensure that the meanings of movements are considered alongside the appearances of movement. Some movements such as stimming have the same functions as many other ways of moving, including dancing and exercising, which could help to reduce stigma around being autistic if reflected in policy and practice. Improving understanding is important for informing how autism is assessed, and how personal experiences of being autistic are heard.

Basolateral Amygdala Functional Connectivity in Alexithymia: Linking Interoceptive Sensibility and Cognitive Empathy

Emotions rely on bodily states, and perceiving the emotions of others depends on awareness of one's own emotional state. However, the intercorrelations among interoception, alexithymia, and empathy are not well understood, and the neural mechanisms behind this connection are also largely unknown. To address these issues, 297 college students participated in this study, completing measures of interoceptive sensibility (IS), empathy and alexithymia and undergoing resting-state fMRI scans. The functional connectivity of the amygdala was analysed to identify the neural substrates of alexithymia, and mediation analyses were conducted to examine the mediation effect of alexithymia and alexithymia-specific amygdala functional connectivity on the relationship between IS and empathy. The results showed that higher levels of IS were associated with increased cognitive empathy through weakened alexithymia. Functional connectivity analysis indicated that right basolateral amygdala (BLA)-left precuneus connectivity was negatively related to alexithymia, while right BLA-left precentral gyrus connectivity was positively related to alexithymia. Furthermore, right BLA-left precuneus connectivity was found to mediate the impact of interoception on cognitive empathy. In conclusion, this study provides valuable insights into the relationships among IS, alexithymia, and empathy. The right BLA-left precuneus connectivity may serve as a shared neural substrate between interoception and cognitive empathy.

Recognition of facial expressions in autism: Effects of face masks and alexithymia

It is often assumed that the recognition of facial expressions is impaired in autism. However, recent evidence suggests that reports of expression recognition difficulties in autistic participants may be attributable to co-occurring alexithymia-a trait associated with difficulties interpreting interoceptive and emotional states-not autism per se. Due to problems fixating on the eye-region, autistic individuals may be more reliant on information from the mouth region when judging facial expressions. As such, it may be easier to detect expression recognition deficits attributable to autism, not alexithymia, when participants are forced to base expression judgements on the eye-region alone. To test this possibility, we compared the ability of autistic participants (with and without high levels of alexithymia) and non-autistic controls to categorise facial expressions (a) when the whole face was visible, and (b) when the lower portion of the face was covered with a surgical mask. High-alexithymic autistic participants showed clear evidence of expression recognition difficulties: they correctly categorised fewer expressions than non-autistic controls. In contrast, low-alexithymic autistic participants were unimpaired relative to non-autistic controls. The same pattern of results was seen when judging masked and unmasked expression stimuli. In sum, we find no evidence for an expression recognition deficit attributable to autism, in the absence of high levels of co-occurring alexithymia, either when participants judge whole-face stimuli or just the eye-region. These findings underscore the influence of co-occurring alexithymia on expression recognition in autism.

Bidirectional relationship between insular grey matter volume and alexithymia: Evidence from a longitudinal study

BACKGROUND

The insula is considered to be involved in emotional cognitive processes, and may be structurally altered in people with alexithymia. However, it remains unclear how the relationship between the insula and alexithymia changes over time. This study aimed to investigate whether alexithymia has longitudinal relationship with the insular structure.

METHODS

Having processed structural MRI data via FreeSurfer, the insula was divided into five sub-regions, and the Toronto Alexithymia Scale was administered to assess alexithymia in the general population. Subsequently, we established the latent change score models between insular sub-regions and the alexithymia (N = 252).

RESULTS

The TAS-20 mean value of the sample at Time 1 was not significantly different by sex (t = -0.993, df = 250, p = 0.321), while the TAS-20 mean value at Time 2 was slightly different by sex (t = 2.025, df = 250, p = 0.044). Most insular grey matter volumes at Time 1 and Time 2 were significantly associated with TAS-20 at Time 2. The baseline alexithymia and insular grey matter volume positively predicted the other's rate of change between Time 1 and Time 2 in a bidirectional way.

LIMITATIONS

This study had a limited number of measurement time points, potential bias due to smaller sample sizes and gender imbalance, as well as the potential for inaccuracy in the self-report measure of alexithymia.

CONCLUSIONS

Time-lagged alexithymia changes and insular grey matter volume changes occur in coupled manner over time, which might improve our understanding of the neurological underpinnings of alexithymia, and shed light on clinical and psychological treatment for alexithymia.

Organizational benefits of neurodiversity: Preliminary findings on autism and the bystander effect

Although the bystander effect is one of the most important findings in the psychological literature, researchers have not explored whether autistic individuals are prone to the bystander effect. The present research examines whether autistic employees are more likely to report issues or concerns in an organization's systems and practices that are inefficient or dysfunctional. By bringing attention to these issues, autistic employees may foster opportunities to improve organizational performance, leading to the development of a more adaptive, high performing, and ethical culture. Thirty-three autistic employees and 34 nonautistic employees completed an online survey to determine whether employees on the autism spectrum (1) are more likely to report they would voice concerns about organizational dysfunctions, (2) are less likely to report they were influenced by the number of other witnesses to the dysfunction, (3) if they do not voice concerns, are more likely to acknowledge the influence of other people on the decision, (4) are less likely to formulate "elaborate rationales" for their decisions to intervene or not, and (5) whether any differences between autistic and nonautistic employees with regards to the first two hypotheses, intervention likelihood and degree of influence, are moderated by individual differences in camouflaging. Results indicate that autistic employees may be less susceptible to the bystander effect than nonautistic employees. As a result, autistic employees may contribute to improvements in organizational performance because they are more likely to identify and report inefficient processes and dysfunctional practices when they witness them. These preliminary findings suggesting potential benefits of neurodiversity in the workplace are promising. However, further research is required.

Listener- Versus Speaker-Oriented Disfluencies in Autistic Adults: Insights From Wearable Eye-Tracking and Skin Conductance Within a Live Face-to-Face Paradigm

PURPOSE

Our study addresses three main questions: (a) Do autistics and neurotypicals produce different patterns of disfluencies, depending on the experimenter's direct versus averted gaze? (b) Are these patterns correlated to gender, skin conductance responses, fixations on the experimenter's face, alexithymia, or social anxiety scores? Lastly, (c) can eye-tracking and electrodermal activity data be used in distinguishing listener- versus speaker-oriented disfluencies?

METHOD

Within a live face-to-face paradigm combining a wearable eye-tracker with electrodermal activity sensors, 80 adults (40 autistics, 40 neurotypicals) defined words in front of an experimenter who was either staring at their eyes (direct gaze condition) or looking elsewhere (averted gaze condition).

RESULTS

Autistics produce less listener-oriented (uh, um) and more speaker-oriented (prolongations, breath) disfluencies than neurotypicals. In both groups, men produce less um than women. Both autistics' and neurotypicals' speech are influenced by whether their interlocutor systematically looks at them in the eyes or not, but their reactions go in opposite directions. Disfluencies seem to primarily be linguistic phenomena as experienced stress, social attention, alexithymia, and social anxiety scores do not influence any of the reported results. Finally, eye-tracking and electrodermal activity data suggest that laughter could be a listener-oriented disfluency.

CONCLUSIONS

This article studies disfluencies in a fine-grained way in autistic and neurotypical adults while controlling for social attention, experienced stress, and experimental condition (direct vs. averted gaze). It adds to current literature by (a) enlightening our knowledge of speech in autism, (b) opening new perspectives on disfluency patterns as important signals in social interaction, (c) addressing theoretical issues on the dichotomy between listener- and speaker-oriented disfluencies, and (d) considering understudied phenomena as potential disfluencies (e.g., laughter, breath).

SUPPLEMENTAL MATERIAL

https://doi.org/10.23641/asha.23549550.

Relationships between alexithymia, interoception, and emotional empathy in autism spectrum disorder

LAY ABSTRACT

Empathy, the ability to understand and share the emotions of others, is a necessary skill for social functioning and can be categorized into cognitive and emotional empathy. There is evidence to suggest that individuals with autism spectrum disorder have difficulties with cognitive empathy, the ability to imagine how another person is thinking or feeling. However, it is unclear if individuals with autism spectrum disorder struggle with emotional empathy, the ability to share and feel emotions others are experiencing. Self-report and interview data were collected to explore the relationships between interoception (individuals' self-reported awareness of sensation from their body such as thirst, heartbeat, etc.), alexithymia (an individual's ability to describe and distinguish between their own emotions), and emotional empathy in 35 youth with autism spectrum disorder and 40 typically developing youth. Greater personal distress to others' emotions and greater difficulty describing and recognizing self-emotions were associated with reporting fewer physical sensations in the body when experiencing emotion in the autism spectrum disorder group. The results of this study suggest that while autism spectrum disorder youth with concomitant alexithymia may experience emotional empathy differently, it should not be characterized as an absence of a capacity for emotional empathy.

Preliminary efficacy of cognitive-behavioral therapy on emotion regulation in adults with autism spectrum disorder: A pilot randomized waitlist-controlled study

Previous studies have demonstrated the clinical utility of cognitive-behavioral therapy in improving emotion regulation in children on the autism spectrum. However, no studies have elucidated the clinical utility of cognitive-behavioral therapy in improving emotion regulation in autistic adults. The aim of the present pilot study was to explore the preliminary clinical utility of a group-based cognitive-behavioral therapy program designed to address emotion regulation skills in autistic adults. We conducted a clinical trial based on a previously reported protocol; 31 participants were randomly allocated to the intervention group and 29 to the waitlist control group. The intervention group underwent an 8-week program of cognitive-behavioral therapy sessions. Two participants from the intervention group withdrew from the study, leaving 29 participants (93.5%) in the group. Compared with the waitlist group, the cognitive-behavioral therapy group exhibited significantly greater pre-to-post (Week 0-8) intervention score improvements on the attitude scale of the autism spectrum disorder knowledge and attitude quiz (t = 2.21, p = 0.03, d = 0.59) and the difficulty describing feelings scale of the 20-item Toronto Alexithymia Scale (t = -2.07, p = 0.04, d = -0.57) in addition to pre-to-follow-up (Week 0-16) score improvements on the emotion-oriented scale of the Coping Inventory for Stressful Situations (t = -2.14, p = 0.04, d = -0.59). Our study thus provides preliminary evidence of the efficacy of the group-based cognitive-behavioral therapy program on emotion regulation in autistic adults, thereby supporting further evaluation of the effectiveness of the cognitive-behavioral therapy program in the context of a larger randomized clinical trial. However, the modest and inconsistent effects underscore the importance of continued efforts to improve the cognitive-behavioral therapy program beyond current standards.

Going beyond the DSM in predicting, diagnosing, and treating autism spectrum disorder with covarying alexithymia and OCD: A structural equation model and process-based predictive coding account

Background

There is much overlap among the symptomology of autistic spectrum disorders (ASDs), obsessive compulsive disorders (OCDs), and alexithymia, which all typically involve impaired social interactions, repetitive impulsive behaviors, problems with communication, and mental health.

Aim

This study aimed to identify direct and indirect associations among alexithymia, OCD, cardiac interoception, psychological inflexibility, and self-as-context, with the DV ASD and depression, while controlling for vagal related aging.

Methodology

The data involved electrocardiogram (ECG) heart rate variability (HRV) and questionnaire data. In total, 1,089 participant's data of ECG recordings of healthy resting state HRV were recorded and grouped into age categories. In addition to this, another 224 participants completed an online survey that included the following questionnaires: Yale-Brown Obsessive Compulsive Scale (Y-BOCS); Toronto Alexithymia Scale 20 (TAS-20); Acceptance and Action Questionnaire (AAQII); Depression, Anxiety, and Stress Scale 21 (DAS21); Multi-dimensional Assessment of Interoceptive Awareness Scale (MAIA); and the Self-as-Context Scale (SAC).

Results

Heart rate variability was shown to decrease with age when controlling for BMI and gender. In the two SEMs produced, it was found that OCD and alexithymia were causally associated with autism and depression indirectly through psychological inflexibility, SAC, and ISen interoception.

Conclusion

The results are discussed in relation to the limitations of the DSM with its categorical focus of protocols for syndromes and provide support for more flexible ideographic approaches in diagnosing and treating mental health and autism within the Extended Evolutionary Meta-Model (EEMM). Graph theory approaches are discussed in their capacity to depict the processes of change potentially even at the level of the relational frame.

Emoji Identification and Emoji Effects on Sentence Emotionality in ASD-Diagnosed Adults and Neurotypical Controls

We investigated ASD-diagnosed adults' and neurotypical (NT) controls' processing of emoji and emoji influence on the emotionality of otherwise-neutral sentences. Study 1 participants categorised emoji representing the six basic emotions using a fixed-set of emotional adjectives. Results showed that ASD-diagnosed participants' classifications of fearful, sad, and surprised emoji were more diverse and less 'typical' than NT controls' responses. Study 2 participants read emotionally-neutral sentences; half paired with sentence-final happy emoji, half with sad emoji. Participants rated sentence + emoji stimuli for emotional valence. ASD-diagnosed and NT participants rated sentences + happy emoji as equally-positive, however, ASD-diagnosed participants rated sentences + sad emoji as more-negative than NT participants. We must acknowledge differential perceptions and effects of emoji, and emoji-text inter-relationships, when working with neurodiverse stakeholders.

The role of interoception in the overlap between eating disorders and autism: Methodological considerations

Significant comorbidity has been demonstrated between feeding and eating disorders and autism. Atypical interoception (perception of bodily signals) may, at least in part, be responsible for this association, as it has been implicated in the aetiology of both conditions. However, significant methodological limitations are impeding progress in this area. This paper provides a brief overview of how interoception has been linked to autism and feeding and eating disorders in both adolescent and adult populations before identifying several issues with current measures of interoception. We suggest that methodological issues may be contributing to the inconsistency in the empirical literature, and provide suggestions for future research.

Atypical interoception is linked to both feeding and eating disorders, and autism and may contribute to the comorbidity between the two.

Existing measures of interoception across cardiac, gastric and respiratory domains are severely limited.

Novel and better‐validated measures of interoception will allow us to better understand the clinical potential of interoceptive training.

A network analysis of interoception, self-awareness, empathy, alexithymia, and autistic traits

Altered interoception has been consistently found in people with autism spectrum disorder (ASD), and this impairment may contribute to social cognitive dysfunctions. However, little is known regarding the intercorrelations between interoceptive sensibility, autistic, alexithymic, empathic, and self-related traits. We recruited 1360 non-clinical college students and adults to investigate the complex inter-relationship between these variables using network analysis. The resultant network revealed patterns connecting autistic traits to interoceptive sensibility, empathy, alexithymia, and self-awareness, with reasonable stability and test-retest consistency. The node of alexithymia exhibited the highest centrality and expected influence. As revealed by the network comparison test, networks constructed in high- and low-autistic subgroups were comparable in global strength and structure. Our findings suggested that alexithymia serves as an important node, bridging interoceptive deficits, self-awareness, and empathic impairments of autism spectrum disorder. The co-morbidity of alexithymia should be considered carefully in future studies of interoceptive impairments and social deficits in ASD.

Action Understanding Promoted by Interoception in Children: A Developmental Model

Action understanding of children develops from simple associative learning to mentalizing. With the rise of embodied cognition, the role of interoception in action observation and action understanding has received more attention. From a developmental perspective, this study proposes a novel developmental model that explores how interoception promotes action understanding of children across ages. In early infancy, most actions observed in infants come from interactions with their caregivers. Babies learn about action effects through automatic interoceptive processing and interoceptive feedback. Interoception in early infancy is not fully developed, such as the not fully developed gastrointestinal tract and intestinal nervous system. Therefore, in early infancy, action understanding is based on low-level and original interoceptive information. At this stage, after observing the actions of others, infants can create mental representations or even imitate actions without external visual feedback, which requires interoception to provide internal reference information. By early childhood, children begin to infer action intentions of other people by integrating various types of information to reach the mentalizing level. Interoception processing requires the integration of multiple internal signals, which promotes the information integration ability of children. Interoception also provides inner information for reasoning about action intention. This review also discussed the neural mechanisms of interoception and possible ways by which it could promote action understanding of children. In early infancy, the central autonomic neural network (CAN) automatically processes and responds to the actions of caregivers on infants, providing interoceptive information for action understanding of infants. In infancy, the growth of the somatomotor system provides important internal reference information for observing and imitating the actions of infants. In early childhood, the development of interoception of children facilitates the integration of internal and external information, which promotes the mentalization of action understanding of children. According to the proposed developmental model of action understanding of children promoted by interoception, there are multilevel and stage-dependent characteristics that impact the role of interoception in action understanding of children.

Room to breathe: Using adaptive architecture to examine the relationship between alexithymia and interoception

OBJECTIVE

Individuals with alexithymia experience difficulties interpreting emotional states in self and others, which has been associated with interoceptive impairment. Current theories are primarily based on subjective and conscious measures of interoceptive sensitivity, such as heartrate detection, but it is unclear whether similar observations would be found for objective or implicit psychophysiological measures. The present exploratory study assesses the potential of a novel assay through the use of adaptive immersive architecture [ExoBuilding].

METHODS

N = 88 participants were screened for alexithymic traits and N = 27 individuals, representing the range of scores, were sampled to participate in the behavioural task. In a repeated-measures design, participants were placed within ExoBuilding and asked to match their respiration to its movement. Performance was compared to a two-dimensional pacer condition. Behavioural (accuracy) and psychophysiological (Respiratory Sinus Arrhythmia [RSA] and heartrate) measures were compared across conditions, and also related to individual alexithymic traits.

RESULTS

Participants with higher levels of alexithymia performed less accurately than participants with lower levels, in both conditions. High-alexithymia participants showed a smaller reduction in heartrate over the course of the ExoBuilding condition than low-alexithymia participants, although there were no differences in RSA between conditions or participants.

CONCLUSION

Alexithymia extends beyond conscious interoceptive activities and is also observed in immersive contexts that usually exert psychophysiological effects on typical occupants. These initial findings highlight the importance of considering both conscious and implicit measures of interoception, and we suggest ways in which theories of alexithymia might benefit from capturing this distinction.

Decreased interoceptive accuracy in children with autism spectrum disorder and with comorbid attention deficit/hyperactivity disorder

Interoception refers to the awareness of internal physiological state. Several previous studies reported that people with autism spectrum disorders (ASD) and adults with attention-deficit/hyperactivity disorder (ADHD) have diverse patterns of interoception, but the extent of literature is limited and inconsistent. This study aimed to investigate the interoceptive accuracy (IA) in children with ASD, children with comorbid ASD and ADHD, and typically developing (TD) children with high and low levels of autistic traits. We administered the eye-tracking interoceptive accuracy task (EIAT) to 30 children with ASD, 20 children with comorbid ASD and ADHD, and 63 TD controls with high and low levels of autistic traits. Parent-report scales concerning ASD and ADHD symptoms were collected. ASD children with and without comorbid ADHD both exhibited lower IA than TD children. Reduced IA was also found in TD children with high-autistic traits relative to those with low-autistic traits. IA was negatively correlated with autistic and ADHD symptoms. Atypical cardiac interoception could be found in children with ASD. Difficulties in sensing and comprehending internal bodily signals in childhood may be related to both ASD and ADHD symptoms.

Atypical interoception as a common risk factor for psychopathology: A review

The inadequacy of a categorial approach to mental health diagnosis is now well-recognised, with many authors, diagnostic manuals and funding bodies advocating a dimensional, trans-diagnostic approach to mental health research. Variance in interoception, the ability to perceive one's internal bodily state, is reported across diagnostic boundaries, and is associated with atypical functioning across symptom categories. Drawing on behavioural and neuroscientific evidence, we outline current research on the contribution of interoception to numerous cognitive and affective abilities (in both typical and clinical populations), and describe the interoceptive atypicalities seen in a range of psychiatric conditions. We discuss the role that interoception may play in the development and maintenance of psychopathology, as well as the ways in which interoception may differ across clinical presentations. A number of important areas for further research on the role of interoception in psychopathology are highlighted.

The relationship between alexithymia and theory of mind: A systematic review

Theory of Mind (ToM), the ability to represent the mental states of oneself and others, is an essential social skill disrupted across many psychiatric conditions. The transdiagnostic nature of ToM impairment means it is plausible that ToM impairment is related to alexithymia (difficulties identifying and describing one's own emotions), as alexithymia is seen across psychiatric conditions. Whilst many studies have examined links between alexithymia and ToM, results are mixed. Therefore, the purpose of this systematic review is to provide a taxonomy of ToM tests and assess their relationship with alexithymia. Tests are grouped according to whether they assess propensity to engage spontaneously in ToM or accuracy of ToM inferences, with tests further subdivided into those that do, and do not, require emotion recognition. A review of 63 suitable studies suggests that alexithymia is often associated with reduced ToM, and inaccurate ToM when tasks require emotion recognition. This latter finding appears due to impaired emotion recognition, rather than ToM impairment per se. Further directions and considerations for future research are discussed.

Psychometric validation and refinement of the Interoception Sensory Questionnaire (ISQ) in adolescents and adults on the autism spectrum

BACKGROUND

Individuals on the autism spectrum are reported to display alterations in interoception, the sense of the internal state of the body. The Interoception Sensory Questionnaire (ISQ) is a 20-item self-report measure of interoception specifically intended to measure this construct in autistic people. The psychometrics of the ISQ, however, have not previously been evaluated in a large sample of autistic individuals.

METHODS

Using confirmatory factor analysis, we evaluated the latent structure of the ISQ in a large online sample of adults on the autism spectrum and found that the unidimensional model fit the data poorly. Using misspecification analysis to identify areas of local misfit and item response theory to investigate the appropriateness of the seven-point response scale, we removed redundant items and collapsed the response options to put forth a novel eight-item, five-response choice ISQ.

RESULTS

The revised, five-response choice ISQ (ISQ-8) showed much improved fit while maintaining high internal reliability. Differential item functioning (DIF) analyses indicated that the items of the ISQ-8 were answered in comparable ways by autistic adolescents and adults and across multiple other sociodemographic groups.

LIMITATIONS

Our results were limited by the fact that we did not collect data for typically developing controls, preventing the analysis of DIF by diagnostic status. Additionally, while this study proposes a new 5-response scale for the ISQ-8, our data were not collected using this method; thus, the psychometric properties for the revised version of this instrument require further investigation.

CONCLUSION

The ISQ-8 shows promise as a reliable and valid measure of interoception in adolescents and adults on the autism spectrum, but additional work is needed to examine its psychometrics in this population. A free online score calculator has been created to facilitate the use of ISQ-8 latent trait scores for further studies of autistic adolescents and adults (available at https://asdmeasures.shinyapps.io/ISQ_score/ ).

Alexithymia explains atypical spatiotemporal dynamics of eye gaze in autism

Recognition of emotional facial expressions is considered to be atypical in autism. This difficulty is thought to be due to the way that facial expressions are visually explored. Evidence for atypical visual exploration of emotional faces in autism is, however, equivocal. We propose that, where observed, atypical visual exploration of emotional facial expressions is due to alexithymia, a distinct but frequently co-occurring condition. In this eye-tracking study we tested the alexithymia hypothesis using a number of recent methodological advances to study eye gaze during several emotion processing tasks (emotion recognition, intensity judgements, free gaze), in 25 adults with, and 45 without, autism. A multilevel polynomial modelling strategy was used to describe the spatiotemporal dynamics of eye gaze to emotional facial expressions. Converging evidence from traditional and novel analysis methods revealed that atypical gaze to the eyes is best predicted by alexithymia in both autistic and non-autistic individuals. Information theoretic analyses also revealed differential effects of task on gaze patterns as a function of alexithymia, but not autism. These findings highlight factors underlying atypical emotion processing in autistic individuals, with wide-ranging implications for emotion research.

Associations Between Mental Health, Interoception, Psychological Flexibility, and Self-as-Context, as Predictors for Alexithymia: A Deep Artificial Neural Network Approach

Background: Alexithymia is a personality trait which is characterized by an inability to identify and describe conscious emotions of oneself and others.

Aim: The present study aimed to determine whether various measures of mental health, interoception, psychological flexibility, and self-as-context, predicted through linear associations alexithymia as an outcome. This also included relevant mediators and non-linear predictors identified for particular sub-groups of participants through cluster analyses of an Artificial Neural Network (ANN) output.

Methodology: Two hundred and thirty participants completed an online survey which included the following questionnaires: Toronto alexithymia scale; Acceptance and Action Questionnaire 2 (AQQII); Positive and Negative Affect Scale (PANAS-SF), Depression, Anxiety, and Stress Scale 21 (DAS21); Multidimensional Assessment of Interoceptive Awareness (MAIA); and the Self-as-Context (SAC) scale. A stepwise backwards linear regression and mediation analysis were performed, as well as a cluster analysis of the non-linear ANN upper hidden layer output.

Results: Higher levels of alexithymia were associated with increased psychological inflexibility, lower positive affect scores, and lower interoception for the subscales of “not distracting” and “attention regulation.” SAC mediated the relation between emotional regulation and total alexithymia. The ANNs accounted for more of the variance than the linear regressions, and were able to identify complex and varied patterns within the participant subgroupings.

Conclusion: The findings were discussed within the context of developing a SAC processed-based therapeutic model for alexithymia, where it is suggested that alexithymia is a complex and multi-faceted condition, which requires a similarly complex, and process-based approach to accurately diagnose and treat this condition.

No preference for direct versus averted gaze in autistic adults: a reinforced preferential looking paradigm

Background

With the overarching objective to gain better insights into social attention in autistic adults, the present study addresses three outstanding issues about face processing in autism. First, do autistic adults display a preference for mouths over eyes; second, do they avoid direct gaze; third, is atypical visual exploration of faces in autism mediated by gender, social anxiety or alexithymia?

Methods

We used a novel reinforced preferential looking paradigm with a group of autistic adults (n = 43, 23 women) pairwise matched on age with neurotypical participants (n = 43, 21 women). Participants watched 28 different pairs of 5 s video recordings of a speaking person: the two videos, simultaneously displayed on the screen, were identical except that gaze was directed at the camera in one video and averted in the other. After a 680 ms transition phase, a short reinforcement animation appeared on the side that had displayed the direct gaze.

Results

None of the groups showed a preference for mouths over eyes. However, neurotypical participants fixated significantly more the stimuli with direct gaze, while no such preference emerged in autistic participants. As the experiment progressed, neurotypical participants also increasingly anticipated the appearance of the reinforcement, based on the location of the stimulus with the direct gaze, while no such anticipation emerged in autistic participants.

Limitations

Our autistic participants scored higher on the social anxiety and alexithymia questionnaires than neurotypicals. Future studies should match neurotypical and autistic participants on social anxiety and alexithymia and complement questionnaires with physiological measures of anxiety.

Conclusions

The absence of preference for direct versus averted gaze in the autistic group is probably due to difficulties in distinguishing eye gaze direction, potentially linked to a reduced spontaneous exploration or avoidance of the eye region. Social attention and preference for direct versus averted gaze correlated with alexithymia and social anxiety scores, but not gender.

Low Emotional Awareness as a Transdiagnostic Mechanism Underlying Psychopathology in Adolescence

The ability to identify and label one's emotions is associated with effective emotion regulation, rendering emotional awareness important for mental health. We evaluated how emotional awareness was related to psychopathology and whether low emotional awareness was a transdiagnostic mechanism explaining the increase in psychopathology during the transition to adolescence and as a function of childhood trauma-specifically violence exposure. In Study 1, children and adolescents (N=120, aged 7-19 years) reported on emotional awareness and psychopathology. Emotional awareness was negatively associated with psychopathology (p-factor) and worsened across age in females but not males. In Study 2 (N=262, aged 8-16 years), we replicated these findings and demonstrated longitudinally that low emotional awareness mediated increases in p-factor as a function of age in females and violence exposure. These findings indicate that low emotional awareness may be a transdiagnostic mechanism linking adolescent development, sex, and trauma with the emergence of psychopathology.

Facial emotion recognition in autistic adult females correlates with alexithymia, not autism

Research on predominantly male autistic samples has indicated that impairments in facial emotion recognition typically associated with autism spectrum conditions are instead due to co-occurring alexithymia. However, whether this could be demonstrated using more realistic facial emotion recognition stimuli and applied to autistic females was unclear. In all, 83 females diagnosed with autism spectrum condition completed online self-report measures of autism spectrum condition severity and alexithymia, and afacial emotion recognition deficit that assessed their ability to identify multimodal displays of complex emotions. Higher levels of alexithymia, but not autism spectrum condition severity, were associated with less accurate facial emotion recognition. Difficulty identifying one’s own feelings and externally oriented thinking were the components of alexithymia that were specifically related to facial emotion recognition accuracy. However, alexithymia (and autism spectrum condition severity) was not associated with speed of emotion processing. The findings are primarily discussed with the theoretical view that perceiving and experiencing emotions share the same neural networks, thus being able to recognise one’s own emotions may facilitate the ability to recognise others’. This study is in line with previous similar research on autistic males and suggests impairments in facial emotion recognition in autistic females should be attributed to co-occurring alexithymia.

Psychometric Properties and Configural Invariance of the Polish - Language Version of the 20-Item Toronto Alexithymia Scale in Non-clinical and Alcohol Addict Persons

AIM

The development and assessment of the psychometric properties of the Polish-language version of the Toronto Alexithymia Scale (Bagby et al., 1994a, b) is described in this article. The aim of this study was to translate the TAS - 20 into Polish and establish the psychometric properties of this instrument evaluating alexithymia.

MATERIALS AND METHODS

Data were collected via self-report measures from a total sample of 676 participants: a total of 180 participants (115 males and 65 females) diagnosed with alcohol dependence, and 496 control group (347 males and 149 females).

RESULTS

Confirmatory factor analyses found the factor structure of the original English-language TAS 20 for the three subscales translated into Polish: Difficulty in Identifying Feeling (DIF); Difficulty in Describing Feeling (DDF); Externally Oriented Thinking (EOT). All three subscales showed good internal consistency in non-clinical group and two subscales, DIF and DDF in alcohol addict group. Several EOT items loaded poorly on their intended factor.

CONCLUSION

The results from the present study indicate that the Polish version of the TAS - 20 is a reliable and valid measure of alexithymia with good levels of internal consistency, homogeneity, and construct validity. We conclude that the TAS-20 has, for the most part, adequate psychometric properties, though interpretation should focus only on the total scale score and DIF and DDF subscales, especially in clinical groups.

Interoception in Anorexia Nervosa: Exploring Associations With Alexithymia and Autistic Traits

BACKGROUND

Previous research on whether interoception is altered in anorexia nervosa (AN) using the heartbeat tracking task has yielded inconsistent results. However, no previous research has examined whether interoception is associated with alexithymia and autistic traits in AN, conditions which are more prevalent in this population and thought to be related to performance in this task. The aim of this study was to explore whether altered interoception in AN is associated with alexithymia and autistic traits.

METHODS

We assessed interoceptive accuracy using the heartbeat tracking task in n = 37 people with AN, and n = 37 age and gender matched healthy controls (HC), and explored within the AN group if interoceptive accuracy was related to self-rated alexithymia or autistic traits. We also assessed self-reported interoceptive ability, and the relationship between subjective and actual performance.

RESULTS

Heartbeat tracking task performance was not found to be altered in the AN group compared to the HC group. However, confidence ratings in task performance in the AN group were lower compared to the HC group. Unlike the HC group, confidence ratings in the AN group did not correlate with task performance. Within the AN group there was no relationship between interoceptive accuracy, alexithymia, and autistic traits, after controlling for the potential confounders of anxiety and depression. There was a relationship between confidence ratings and illness severity in the AN group.

CONCLUSION

The results found no differences between heartbeat tracking task performance in people with AN compared to HC. There was no association between task performance, alexithymia and autistic traits in AN. Results do suggest that people with AN exhibit lowered confidence in their task performance, and that they may lack insight into this performance compared to HC. The findings are discussed in the context of potential significant limitations of the heartbeat tracking task, with recommendations for future research into interoception in AN.

Orally administered oxytocin alters brain activation and behaviors of pre-weaning mice

Oxytocin (OXT) regulates adult social behavior and has been implicated in its development. Because mammalian milk contains OXT and we have recently identified OXT receptors (OXTR) in the face and oronasal cavity of pre-weaning mice, we hypothesize that orally applied OXT may impact brain activity and acute behavior in developing mice. Oral OXT may have effects in the absence of sensory stimulation or perhaps by modulating sensory input, such as whisker stimulation. The present study investigates the acute c-Fos response in the paraventricular nucleus of the hypothalamus (PVN) and along whisker sensory processing brain regions (trigeminothalamocortical circuit) to orally applied OXT, compared to saline, with and without whisker stimulation in postnatal day (P) 14 and P21 male and female mice. Acute behavioral responses were also quantified after oral OXT with whisker stimulation in a non-social context. Oral OXT with and without whisker stimulation increased c-Fos activity in the PVN of males and decreased c-Fos in the ventroposterior medial thalamus in both males and females compared to saline. Additionally, oral OXT with whisker stimulation decreased c-Fos activity across whisker sensory processing brain regions in males and females and decreased c-Fos activity in the trigeminal motor nucleus of females. Lastly, oral OXT with whisker stimulation increased males' locomotor behavior and decreased females' oromotor behavior compared to saline-treated controls. These data indicate that orally applied OXT has acute brain and behavioral effects on developing mice. OXT-modulated sensory signals may bias brain and behavior development toward the social world.

Classifying individual differences in interoception: Implications for the measurement of interoceptive awareness

It has been suggested that individual differences in interoception (the perception of the body’s internal state) can be divided into three distinct dimensions: interoceptive accuracy (performance on objective tests of interoceptive accuracy), interoceptive sensibility (self-reported beliefs concerning one’s own interoception) and interoceptive awareness (a metacognitive measure indexed by the correspondence between interoceptive accuracy and interoceptive sensibility). Research conducted under this model underscores the importance of interoceptive awareness for a variety of disorder-specific and transdiagnostic symptoms. However, the clinical importance of interoceptive awareness means that this aspect of interoception warrants further scrutiny, and such scrutiny suggests that revision of the three-dimensional model of interoception is necessary. In this theoretical paper, we outline such a revision, highlighting a need to distinguish not only how interoception is measured (objective measures vs. self-report), but also what is measured (accuracy vs. attention). The model refines how individual differences in interoception are categorised, with important consequences for the measurement of interoceptive awareness. Such a revision may help researchers to identify the strengths and weaknesses in interoception observed across clinical conditions, and to isolate clinically relevant individual differences.

Functional neuroanatomy of interoceptive processing in children and adolescents: a pilot study

In adults, interoception - the sense of the physiological condition of the body - appears to influence emotion processing, cognition, behavior and various somatic and mental health disorders. Adults demonstrate frontal-insula-parietal-anterior cingulate cortex activation during the heartbeat detection task, a common interoceptive measure. Little, however, is known about the functional neuroanatomy underlying interoception in children. The current pilot study examined interoceptive processing in children and adolescents with fMRI while using the heartbeat detection task. Our main findings demonstrate that children as young as the age of six activate the left insula, cuneus, inferior parietal lobule and prefrontal regions. These findings are similar to those in adults when comparing heartbeat and tone detection conditions. Age was associated with increased activation within the dACC, orbital frontal cortex and the mid-inferior frontal gyri. Thus, our pilot study may provide important information about the neurodevelopment of interoceptive processing abilities in children and a task for future interoception neuroimaging studies in children.

The Feeling of Me Feeling for You: Interoception, Alexithymia and Empathy in Autism

Following recent evidence for a link between interoception, emotion and empathy, we investigated relationships between these factors in autism spectrum disorder (ASD). 26 adults with ASD and 26 healthy participants completed tasks measuring interoception, alexithymia and empathy. ASD participants with alexithymia demonstrated lower cognitive and affective empathy than ASD participants without alexithymia. ASD participants showed reduced interoceptive sensitivity (IS), and also reduced interoceptive awareness (IA). IA was correlated with empathy and alexithymia, but IS was related to neither. Alexithymia fulfilled a mediating role between IA and empathy. Our findings are suggestive of an alexithymic subgroup in ASD, with distinct interoceptive processing abilities, and have implications for diagnosis and interventions.

Facial mimicry, facial emotion recognition and alexithymia in post-traumatic stress disorder

Individuals with post-traumatic stress disorder (PTSD) show abnormalities in higher-order emotional processes, including emotion regulation and recognition. However, automatic facial responses to observed facial emotion (facial mimicry) has not yet been investigated in PTSD. Furthermore, whereas deficits in facial emotion recognition have been reported, little is known about contributing factors. We thus investigated facial mimicry and potential effects of alexithymia and expressive suppression on facial emotion recognition in PTSD. Thirty-eight PTSD participants, 43 traumatized and 33 non-traumatized healthy controls completed questionnaires assessing alexithymia and expressive suppression. Facial electromyography was measured from the muscles zygomaticus major and corrugator supercilii during a facial emotion recognition task. Corrugator activity was increased in response to negative emotional expressions compared to zygomaticus activity and vice versa for positive emotions, but no significant group differences emerged. Individuals with PTSD reported greater expressive suppression and alexithymia than controls, but only levels of alexithymia predicted lower recognition of negative facial expressions. While automatic facial responses to observed facial emotion seem to be intact in PTSD, alexithymia, but not expressive suppression, plays an important role in facial emotion recognition of negative emotions. If replicated, future research should evaluate whether successful interventions for alexithymia improve facial emotion recognition abilities.

The Role of Language in Alexithymia: Moving Towards a Multiroute Model of Alexithymia

Alexithymia is characterized by difficulty identifying and describing one’s own emotion. Identifying and describing one’s emotion involves several cognitive processes, so alexithymia may result from a number of impairments. Here we propose the alexithymia language hypothesis—the hypothesis that language impairment can give rise to alexithymia—and critically review relevant evidence from healthy populations, developmental disorders, adult-onset illness, and acquired brain injury. We conclude that the available evidence is supportive of the alexithymia–language hypothesis, and therefore that language impairment may represent one of multiple routes to alexithymia. Where evidence is lacking, we outline which approaches will be useful in testing this hypothesis.

Interoceptive Awareness, Alexithymia, and Sexual Function

Research in women suggests a relation between sexual difficulties and lower interoceptive awareness, the conscious perception of internal bodily states. Lower interoceptive awareness is theoretically linked to greater alexithymia, which has been related to sexual dysfunctions. Hence, we examined the relations of interoceptive awareness and alexithymia with several dimensions of sexual functioning in a nonclinical sample of both sexes. Methods: Three hundred forty Portuguese (228 women, 112 men) completed the Toronto Alexithymia Scale (TAS-20) and the Multidimensional Assessment of Interoceptive Awareness (MAIA). Women additionally completed the Female Sexual Function Index (FSFI) and the Female Sexual Distress Scale-Revised (FSDS-R). Men additionally completed the International Index of Erectile Function (IIEF) and one question on difficulties delaying ejaculation. Greater alexithymia correlated with lesser interoceptive awareness. For women, greater alexithymia and lesser interoceptive awareness correlated with lesser arousal, lesser lubrication, more orgasm difficulties, more dissatisfaction, more pain, and more sexual distress. Higher female desire correlated with greater interoceptive awareness, but was unrelated to alexithymia. In men, lesser interoceptive awareness correlated with more difficulties delaying ejaculation, and greater alexithymia correlated with more erectile difficulties. The present investigation corroborates that awareness of emotions and internal bodily states is important for sexual functioning.

Direct and indirect effects of age on interoceptive accuracy and awareness across the adult lifespan

Various aspects of physical and mental health have been linked to an individual’s ability to perceive the physical condition of their body (‘interoception’). In addition, numerous studies have demonstrated a role for interoception in higher-order cognitive abilities such as decision-making and emotion processing. The importance of interoception for health and typical cognitive functioning has prompted interest in how interoception varies over the lifespan. However, few studies have investigated interoception into older adulthood, and no studies account for the set of physiological changes that may influence task performance. The present study examined interoception from young to very late adulthood (until 90 years of age) utilising a self-report measure of interoception (Study One) and an objective measure of cardiac interoception (Study Two). Across both studies, interoception decreased with age, and changes in interoceptive accuracy were observed which were not explained by accompanying physiological changes. In addition to a direct effect of age on interoception, an indirect effect of ageing on cardiac interoceptive accuracy mediated by body mass index (BMI) was found, such that ageing was associated with increased BMI which was, in turn, associated with reduced interoceptive accuracy. Such findings support and extend previous research demonstrating interoceptive decline with advancing age, and highlight the importance of assessing whether decreasing interoceptive ability is responsible for some aspects of age-related ill-health and cognitive impairment.

Investigating alexithymia in autism: A systematic review and meta-analysis

BACKGROUND

New research suggests that, rather than representing a core feature of autism spectrum disorder (ASD), emotional processing difficulties reflect co-occurring alexithymia. Autistic individuals with alexithymia could therefore represent a specific subgroup of autism who may benefit from tailored interventions. The aim of this systematic review and meta-analysis was to explore the nature and prevalence of alexithymia in autism using the Toronto Alexithymia Scale (TAS).

METHODS

Online scientific databases were searched systematically for studies on ASD popu lations using the TAS. Meta-analyses were performed to evaluate differences in scores between the ASD and neurotypical groups, and to determine the prevalence of alexithymia in these populations.

RESULTS

15 articles comparing autistic and neurotypical (NT) groups were identified. Autistic people scored significantly higher on all scores compared to the NT group. There was also a higher prevalence of alexithymia in the ASD group (49.93% compared to 4.89%), with a significantly increased risk of alexithymia in autistic participants.

CONCLUSIONS

This review highlights that alexithymia is common, rather than universal, in ASD, supporting a growing body of evidence that co-occurring autism and alexithymia represents a specific subgroup in the ASD population that may have specific clinical needs. More research is needed to understand the nature and implications of co-occurring ASD and alexithymia.

Regional homogeneity of intrinsic brain activity related to the main alexithymia dimensions

Background

Alexithymia is a multidimensional personality construct.

Objective

This study aims to investigate the neuronal correlates of each alexithymia dimension by examining the regional homogeneity (ReHo) of intrinsic brain activity in a resting situation.

Methods

From university freshmen, students with alexithymia and non-alexithymia were recruited. Their alexithymic traits were assessed using the Toronto Alexithymia Scale-20. The ReHo was examined using a resting-state functional MRI approach.

Results

This study suggests significant group differences in ReHo in multiple brain regions distributed in the frontal lobe, parietal lobe, temporal lobe, occipital lobe and insular cortex. However, only the ReHo in the insula was positively associated with difficulty identifying feelings, a main dimension of alexithymia. The ReHo in the lingual gyrus, precentral gyrus and postcentral gyrus was positively associated with difficulty describing feelings in participants with alexithymia. Lastly, the ReHo in the right dorsomedial prefrontal cortex (DMPFC_R) was negatively related to the externally oriented thinking style of participants with alexithymia.

Conclusion

In conclusion, these results suggest that the main dimensions of alexithymia are correlated with specific brain regions’ function, and the role of the insula, lingual gyrus, precentral gyrus, postcentral gyrus and DMPFC_R in the neuropathology of alexithymia should be further investigated.

Interoceptive impairments do not lie at the heart of autism or alexithymia

Quattrocki and Friston (2014) argued that abnormalities in interoception—the process of representing one’s internal physiological states—could lie at the heart of autism, because of the critical role interoception plays in the ontogeny of social-affective processes. This proposal drew criticism from proponents of the alexithymia hypothesis, who argue that social-affective and underlying interoceptive impairments are not a feature of autism per se, but of alexithymia (a condition characterized by difficulties describing and identifying one’s own emotions), which commonly co-occurs with autism. Despite the importance of this debate for our understanding of autism spectrum disorder (ASD), and of the role of interoceptive impairments in psychopathology, more generally, direct empirical evidence is scarce and inconsistent. Experiment 1 examined in a sample of 137 neurotypical (NT) individuals the association among autistic traits, alexithymia, and interoceptive accuracy (IA) on a standard heartbeat-tracking measure of IA. In Experiment 2, IA was assessed in 46 adults with ASD (27 of whom had clinically significant alexithymia) and 48 NT adults. Experiment 1 confirmed strong associations between autistic traits and alexithymia, but yielded no evidence to suggest that either was associated with interoceptive difficulties. Similarly, Experiment 2 provided no evidence for interoceptive impairments in autistic adults, irrespective of any co-occurring alexithymia. Bayesian analyses consistently supported the null hypothesis. The observations pose a significant challenge to notions that interoceptive impairments constitute a core feature of either ASD or alexithymia, at least as far as the direct perception of interoceptive signals is concerned.

This article suggests that impairments in interoception—the process of representing one’s internal physiological states—do not lie at the heart of either autism or alexithymia.

Being a Beast Machine: The Somatic Basis of Selfhood

Modern psychology has long focused on the body as the basis of the self. Recently, predictive processing accounts of interoception (perception of the body 'from within') have become influential in accounting for experiences of body ownership and emotion. Here, we describe embodied selfhood in terms of 'instrumental interoceptive inference' that emphasises allostatic regulation and physiological integrity. We apply this approach to the distinctive phenomenology of embodied selfhood, accounting for its non-object-like character and subjective stability over time. Our perspective has implications for the development of selfhood and illuminates longstanding debates about relations between life and mind, implying, contrary to Descartes, that experiences of embodied selfhood arise because of, and not in spite of, our nature as 'beast machines'.

The Actions and Feelings Questionnaire in Autism and Typically Developed Adults

Impaired motor cognition may underpin empathy problems in autism. The actions and feelings questionnaire (AFQ), designed to examine individual differences in motor cognition, was completed fully by 1391 adults, of whom 326 reported a diagnosis of an autism spectrum condition (ASC). A confirmatory factor analysis supported a 3 factor model. The AFQ total and ‘feelings’ subscale scores correlated highly with the EQ and ROC curves were similar. Our findings suggest that individual differences in empathic traits are heavily accounted for by variance in mechanisms that serve sensorimotor learning (motor cognition) in relation to emotional states. The AFQ is a self-report tool that provides a valid indicator of autism status in adult populations.

Language and alexithymia: Evidence for the role of the inferior frontal gyrus in acquired alexithymia

The clinical relevance of alexithymia, a condition associated with difficulties identifying and describing one's own emotion, is becoming ever more apparent. Increased rates of alexithymia are observed in multiple psychiatric conditions, and also in neurological conditions resulting from both organic and traumatic brain injury. The presence of alexithymia in these conditions predicts poorer regulation of one's emotions, decreased treatment response, and increased burden on carers. While clinically important, the aetiology of alexithymia is still a matter of debate, with several authors arguing for multiple 'routes' to impaired understanding of one's own emotions, which may or may not result in distinct subtypes of alexithymia. While previous studies support the role of impaired interoception (perceiving bodily states) in the development of alexithymia, the current study assessed whether acquired language impairment following traumatic brain injury, and damage to language regions, may also be associated with an increased risk of alexithymia. Within a sample of 129 participants with penetrating brain injury and 33 healthy controls, neuropsychological testing revealed that deficits in a non-emotional language task, object naming, were associated with alexithymia, specifically with difficulty identifying one's own emotions. Both region-of-interest and whole-brain lesion analyses revealed that damage to language regions in the inferior frontal gyrus was associated with the presence of both this language impairment and alexithymia. These results are consistent with a framework for acquired alexithymia that incorporates both interoceptive and language processes, and support the idea that brain injury may result in alexithymia via impairment in any one of a number of more basic processes.

Emotion recognition associated with polymorphism in oxytocinergic pathway gene ARNT2

The ability to correctly understand the emotional expression of another person is essential for social relationships and appears to be a partly inherited trait. The neuropeptides oxytocin and vasopressin have been shown to influence this ability as well as face processing in humans. Here, recognition of the emotional content of faces and voices, separately and combined, was investigated in 492 subjects, genotyped for 25 single nucleotide polymorphisms (SNPs) in eight genes encoding proteins important for oxytocin and vasopressin neurotransmission. The SNP rs4778599 in the gene encoding aryl hydrocarbon receptor nuclear translocator 2 (ARNT2), a transcription factor that participates in the development of hypothalamic oxytocin and vasopressin neurons, showed an association that survived correction for multiple testing with emotion recognition of audio-visual stimuli in women (n = 309). This study demonstrates evidence for an association that further expands previous findings of oxytocin and vasopressin involvement in emotion recognition.

Oxytocin Modulates Attention Switching Between Interoceptive Signals and External Social Cues

Emotional experience involves an integrated interplay between processing of external emotional cues and interoceptive feedback, and this is impaired in a number of emotional disorders. The neuropeptide oxytocin (OT) enhances the salience of external social cues but its influence on interoception is unknown. The present pharmaco-fMRI study therefore investigated whether OT enhances interoceptive awareness and if it influences the interplay between interoceptive and salience processing. In a randomized, double-blind, between-subject, design study 83 subjects received either intranasal OT or placebo. In Experiment 1, subjects performed a heartbeat detection task alone, while in Experiment 2 they did so while viewing both neutral and emotional face stimuli. Interoceptive accuracy and neural responses in interoceptive and salience networks were measured. In Experiment 1, OT had no significant influence on interoceptive accuracy or associated activity in the right anterior insula (AI) and dorsal anterior cingulate cortex. However, in Experiment 2 when face stimuli were also presented, OT decreased interoceptive accuracy and increased right AI activation and its functional connectivity with the left posterior insula (PI), with the latter both being negatively correlated with accuracy scores. The present study provides the first evidence that while OT does not influence processing of interoceptive cues per se it may switch attention away from them towards external salient social cues by enhancing right AI responses and its control over the PI. Thus OT may help regulate the interplay between interoceptive and external salience processing within the insula and could be of potential therapeutic benefit for emotional disorders.