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.

Three key questions to move towards a theoretical framework of visuospatial perspective taking.

What would a theory of visuospatial perspective taking (VSPT) look like? Here, ten researchers in the field, many with different theoretical viewpoints and empirical approaches, present their consensus on the three big questions we need to answer in order to bring this theory (or these theories) closer.

The Oxford Face Matching Test: Short-form alternative.

A recently published test of face perception, the Oxford Face Matching Test, asks participants to make two judgements: whether two faces are of the same individual and how perceptually similar the two faces are. In this study, we sought to determine to what extent the test can be shortened by removing the perceptual similarity judgements and whether this affects test performance. In Experiment 1, participants completed two versions of the test, with and without similarity judgements, in separate sessions in counterbalanced order. The version without similarity judgements took approximately 40% less time to complete. Performance on the matching judgements did not differ across versions and the correlation in accuracy across the two versions was comparable with the originally reported test-retest reliability value. Experiment 2 validated the version without similarity judgements against other measures, demonstrating moderate relationships with other face matching, memory, and self-report face perception measures. These data indicate that a test version without the similarity judgements can substantially reduce administration time without affecting test performance.

Differences in own-face but not own-name discrimination between autistic and neurotypical adults: A fast periodic visual stimulation-EEG study.

Self-related processing is thought to be altered in autism, with several studies reporting that autistic individuals show a diminished neural response relative to neurotypicals for their own name and face. However, evidence remains scarce and is mostly based on event-related potential studies. Here, we used EEG to measure the neural activity of autistic adults (20 for faces, 27 for names) and neurotypical adults (24 for faces, 25 for names) while they were watching rapidly alternating faces and names, through a relatively new technique called Fast Periodic Visual Stimulation. We presented strangers' faces or names at a base frequency of 5.77 Hz, while one's own, a close other's, and a specific stranger's face/name was presented at an oddball frequency of 1.154 Hz. The neurotypical group showed a significantly greater response to their own face than both close other and stranger faces, and a greater response for close other than for stranger faces. In contrast, in the autism group, own and close other faces showed stronger responses than the stranger's face, but the difference between own and close other faces was not significant in a bilateral parieto-occipital cluster. No group differences in the enhanced response to familiar names were found. These results replicate and extend results obtained using traditional electroencephalographic techniques which suggest atypical responses to self-relevant stimuli in autism.

Measuring trust with the Wayfinding Task: Implementing a novel task in immersive virtual reality and desktop setups across remote and in-person test environments.

Trust is a key feature of social relationships. Common measures of trust, questionnaires and economic games, lack ecological validity. Hence, we sought to introduce an immersive, virtual reality (VR) measure for the behavioral assessment of trust across remote and in-person settings, building on the maze task of Hale et al. (2018). Our 'Wayfinding Task' consists of an interconnected urban environment for participants to navigate on the advice of two characters of differing trustworthiness. We present four studies implementing the Wayfinding Task in remote and in-person testing environments and comparing performance across head-mounted display (HMD)-based VR and desktop setups. In each study, the trustworthiness of two virtual characters was manipulated, through either a fact sheet providing trustworthiness information, or a behavior-based trustworthiness manipulation task termed the Door Game, based on Van der Biest et al., 2020. Participants then completed the Wayfinding Task. Overall, we found that participant behavior in the Wayfinding Task reflected the relative trustworthiness of the two characters; in particular, the trustworthy character was approached more often for advice, reflecting data from our Door Game. We found mostly null results for our novel outcome measure, interpersonal distance. Remote testing successfully achieved these effects. While HMD-based VR and desktop setups both showed these effects, there was a stronger effect of trustworthiness in the HMD VR version of the task. These results have implications for the measurement of trust in behavioral settings and the use of remote and VR-based testing in social experiments.

Independent measurement of face perception, face matching, and face memory reveals impairments in face perception and memory, but not matching, in autism.

Multiple psychological processes are required in order for a face to be recognised from memory. However, when testing face memory using tasks such as the Cambridge Face Memory Task (CFMT), it is rare for studies to attempt to account for individual differences in face perception and face matching in order to isolate variance in face memory specifically. In Study 1, the Oxford Face Matching Test (OFMT) was used to assess face matching and face perception in a large sample of participants (N = 1,112). Results revealed independent contributions of face perception and matching to CFMT performance, and these results replicated with the Glasgow Face Matching Test. In Study 2, the same procedure was used to test face perception, face matching and face memory in a group of 57 autistic adults and a matched neurotypical control group. Results revealed impaired face perception and memory in the individuals with autism, but intact face matching. Face perception may therefore act as a potential intervention target for individuals with autism who exhibit face recognition impairments.

Coherence and divergence in autonomic-subjective affective space.

A central tenet of many theories of emotion is that emotional states are accompanied by distinct patterns of autonomic activity. However, experimental studies of coherence between subjective and autonomic responses during emotional states provide little evidence of coherence. Crucially, previous studies investigating coherence have either adopted univariate approaches or made limited use of multivariate analytic approaches by investigating subjective and autonomic responses separately. The current study addressed this question using a multivariate dimensional approach to build a common autonomic-subjective affective space incorporating subjective responses and three different autonomic signals (heart rate, skin conductance response, and pupil diameter), measured during an emotion-inducing task, in 51 participants. Results showed that autonomic and subjective responses could be adequately described in a two-dimensional affective space. The first dimension included contributions from subjective and autonomic responses, indicating coherence, while contributions to the second dimension were almost exclusively of autonomic covariance. Thus, while there was a degree of coherence between autonomic and subjective emotional responses, there was substantial structure in autonomic responses that did not covary with subjective emotional experience. This study, therefore, contributes new insights into the relationship between subjective and autonomic emotional responses, and provides a framework for future multimodal emotion research, enabling both hypothesis- and data-driven testing.

Is action understanding an automatic process? Both cognitive and perceptual processing are required for the identification of actions and intentions.

The ability to identify others' actions and intentions, "action understanding," is crucial for successful social interaction. Under direct accounts, action understanding takes place without the involvement of inferential processes, a claim that has yet to be tested using behavioural measures. Using a dual-task paradigm, the present study aimed to establish whether the identification of others' actions and intentions depends on automatic or inferential processing, by manipulating working memory load during performance of a task designed to target the identification of actions and intentions. Experiment 1 tested a novel action understanding task targeting action identification and intention identification. This task was then combined with two working memory manipulations (cognitive: Experiment 2; perceptual: Experiment 3) to determine whether action identification and intention identification are disrupted by concurrent cognitive or perceptual load. Both action identification and intention identification were impaired by concurrent cognitive and perceptual processing, indicating that action understanding requires additional perceptual and cognitive resources. These findings contradict a direct account of action understanding.

Novel theory of mind task demonstrates representation of minds in mental state inference.

Theory of mind (ToM), the ability to represent the mental states of oneself and others, is argued to be central to human social experience, and impairments in this ability are thought to underlie several psychiatric and developmental conditions. To examine the accuracy of mental state inferences, a novel ToM task was developed, requiring inferences to be made about the mental states of 'Targets', prior participants who took part in a videoed mock interview. Participants also made estimates of the Targets' personality traits. These inferences were compared to ground-truth data, provided by the Targets, of their true traits and mental states. Results from 55 adult participants demonstrated that trait inferences were used to derive mental state inferences, and that the accuracy of trait estimates predicted the accuracy of mental state inferences. Moreover, the size and direction of the association between trait accuracy and mental state accuracy varied according to the trait-mental state combination. The accuracy of trait inferences was predicted by the accuracy of participants' understanding of trait covariation at the population level. Findings are in accordance with the Mind-space theory, that representation of the Target mind is used in the inference of their mental states.

Individuals with developmental prosopagnosia show independent impairments in face perception, face memory and face matching.

Individuals with developmental prosopagnosia (DP) all exhibit impairments in face memory, but the specificity of these face memory impairments is debated. One problem is that standard behavioural tasks are not able to provide independent measurement of face perception, face memory, and face matching (the decision process required to judge whether two instances of a face are of the same individual or different individuals). The present study utilised a new test of face matching, the Oxford Face Matching Test (OFMT), and a novel analysis strategy to derive these independent indices. Twenty-nine individuals with DP and the same number of matched neurotypical controls completed the OFMT, the Glasgow Face Matching Test, and the Cambridge Face Memory Test. Results revealed individuals with DP exhibit impairments in face perception, face memory and face matching. Collectively, these results suggest that face processing impairments in DP are more comprehensive than has previously been suggested.

Furthering the language hypothesis of alexithymia: An integrated review and meta-analysis.

Alexithymia, including the inability to identify and express one's own feelings, is a subclinical condition responsible for some of the socioemotional symptoms seen across a range of psychiatric conditions. The language hypothesis of alexithymia posits a language-mediated disruption in the development of discrete emotion concepts from ambiguous affective states, exacerbating the risk of developing alexithymia in language-impaired individuals. To provide a critical evaluation, a systematic review and meta-analysis of 29 empirical studies of language functioning in alexithymia was performed. A modest association was found between alexithymia and multi-domain language deficits (r = -0.14), including structural language, pragmatics, and propensity to use emotional language. A more theoretically-relevant subsample analysis comparing alexithymia levels in language-impaired and typical individuals revealed larger effects, but a limited number of studies adopted this approach. A synthesis of 11 emotional granularity studies also found an association between alexithymia and reduced emotional granularity (r = -0.10). Language impairments seem to increase the risk of alexithymia. Heterogeneous samples and methods suggest the need for studies with improved alexithymia assessments.

Mirror neuron brain regions contribute to identifying actions, but not intentions.

Previous studies have struggled to determine the relationship between mirror neuron brain regions and two distinct "action understanding" processes: identifying actions and identifying the intentions underlying those actions. This may be because the identification of intentions from others' actions requires an initial action identification process. Disruptive transcranial magnetic stimulation was administered to left inferior frontal gyrus (lIFG) during a novel cognitive task to determine which of these "action understanding" processes is subserved by mirror neuron brain regions. Participants identified either the actions performed by observed hand actions or the intentions underlying those actions. The extent to which intention identification was disrupted by lIFG (vs. control site) stimulation was dependent on the level of disruption to action identification. We subsequently performed functional magnetic resonance imaging during the same task. During action identification, responses were widespread within mirror neuron areas including lIFG and inferior parietal lobule. However, no independent responses were found in mirror neuron brain regions during intention identification. Instead, responses occurred in brain regions associated with two distinct mentalizing localizer tasks. This supports an account in which mirror neuron brain regions are involved in an initial action identification process, but the subsequent identification of intentions requires additional processing in mentalizing brain regions.

Egocentric biases are predicted by the precision of self-related predictions.

According to predictive processing theories, emotional inference involves simultaneously minimising discrepancies between predictions and sensory evidence relating to both one's own and others' states, achievable by altering either one's own state (empathy) or perception of another's state (egocentric bias) so they are more congruent. We tested a key hypothesis of these accounts, that predictions are weighted in inference according to their precision (inverse variance). If correct, increasingly precise self-related predictions should be associated with increasingly biased perception of another's emotional expression. We manipulated predictions about upcoming own-pain (low or high magnitude) using cues that afforded either precise (a narrow range of possible magnitudes) or imprecise (a wide range) predictions. Participants judged pained facial expressions presented concurrently with own-pain to be more intense when own-pain was greater, and precise cues increased this biasing effect. Implications of conceptualising interpersonal influence in terms of predictive processing are discussed.

Investigating the sense of agency and its relation to subclinical traits using a novel task.

Tasks measuring the sense of agency often manipulate the predictability of action outcomes by introducing spatial deviation. However, the extent to which spatial predictability of an outcome influences the sense of agency when spatial deviation is controlled for remains untested. We used a novel task to investigate the effect of several factors (action-outcome contingency, spatial deviation, and spatial predictability when controlling for spatial deviation of action outcomes) on the sense of agency. We also investigated trait predictors of metacognition of agency-the degree to which participants' confidence in their agency judgements corresponds to the accuracy of those judgements. Initial and replication samples completed contingency, deviation, and predictability versions of the task. Across samples, participants' sense of agency was impacted by action-outcome contingency and spatial deviation of action outcomes. Manipulation of the spatial predictability of action outcomes did not reliably impact the sense of agency. Metacognition of agency was related to alexithymic traits-higher alexithymia scores were associated with reduced metacognition of agency.

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.

What Happened to Mirror Neurons?

Ten years ago, Perspectives in Psychological Science published the Mirror Neuron Forum, in which authors debated the role of mirror neurons in action understanding, speech, imitation, and autism and asked whether mirror neurons are acquired through visual-motor learning. Subsequent research on these themes has made significant advances, which should encourage further, more systematic research. For action understanding, multivoxel pattern analysis, patient studies, and brain stimulation suggest that mirror-neuron brain areas contribute to low-level processing of observed actions (e.g., distinguishing types of grip) but not to high-level action interpretation (e.g., inferring actors' intentions). In the area of speech perception, although it remains unclear whether mirror neurons play a specific, causal role in speech perception, there is compelling evidence for the involvement of the motor system in the discrimination of speech in perceptually noisy conditions. For imitation, there is strong evidence from patient, brain-stimulation, and brain-imaging studies that mirror-neuron brain areas play a causal role in copying of body movement topography. In the area of autism, studies using behavioral and neurological measures have tried and failed to find evidence supporting the "broken-mirror theory" of autism. Furthermore, research on the origin of mirror neurons has confirmed the importance of domain-general visual-motor associative learning rather than canalized visual-motor learning, or motor learning alone.

Non-invasive stimulation of the social brain: the methodological challenges.

Use of non-invasive brain stimulation methods (NIBS) has become a common approach to study social processing in addition to behavioural, imaging and lesion studies. However, research using NIBS to investigate social processing faces challenges. Overcoming these is important to allow valid and reliable interpretation of findings in neurotypical cohorts, but also to allow us to tailor NIBS protocols to atypical groups with social difficulties. In this review, we consider the utility of brain stimulation as a technique to study and modulate social processing. We also discuss challenges that face researchers using NIBS to study social processing in neurotypical adults with a view to highlighting potential solutions. Finally, we discuss additional challenges that face researchers using NIBS to study and modulate social processing in atypical groups. These are important to consider given that NIBS protocols are rarely tailored to atypical groups before use. Instead, many rely on protocols designed for neurotypical adults despite differences in brain function that are likely to impact response to NIBS.

Regulating mirroring of emotions: A social-specific mechanism?

There is evidence that humans mirror others' emotional responses: brain responses to observed and experienced emotion overlap, and reaction time costs of observing others' pain suggest that others' emotional states interfere with our own. Such emotional mirroring requires regulation to prevent personal distress. However, currently it is unclear whether this "empathic interference effect" is uniquely social, arising only from the observation of human actors, or also from the observation of non-biological objects in "painful" states. Moreover, the degree to which this interference relates to individual differences in self-reported levels of empathy is yet to be revealed. We introduce a modified pain observation task, measuring empathic interference effects induced by observation of painful states applied to both biological and non-biological stimuli. An initial validation study (N = 50) confirmed that painful states applied to biological stimuli were rated explicitly as more painful than non-painful states applied to biological stimuli, and also than both painful and non-painful states applied to non-biological stimuli. Subsequently, across two independent discovery (N = 83) and replication (N = 80) samples, the task elicited slowing of response times during the observation of painful states when compared to non-painful states, but the magnitude of this effect did not differ between biological and non-biological stimuli. Little evidence was found for reliable relationships between empathic interference and self-reported empathy. Caution should therefore be taken in using the current task to pursue an individual differences approach to empathic interference, but the task shows promise for investigating the specificity of the mechanism involved in regulating emotional mirroring.

Validation of Gazepoint low-cost eye-tracking and psychophysiology bundle.

Eye-tracking and recording of physiological signals are increasingly used in research within cognitive science and human-computer interaction. For example, gaze position and measures of autonomic arousal, including pupil dilation, skin conductance (SC), and heart rate (HR), provide an indicator of cognitive and physiological processes. The growing popularity of these techniques is partially driven by the emergence of low-cost recording equipment and the proliferation of open-source software for data collection and analysis of such signals. However, the use of new technology requires investigation of its reliability and validation with respect to real-world usage and against established technologies. Accordingly, in two experiments (total N = 69), we assessed the Gazepoint GP3-HD eye-tracker and Gazepoint Biometrics (GPB) system from Gazepoint. We show that the accuracy, precision, and robustness of the eye-tracker are comparable to competing systems. While fixation and saccade events can be reliably extracted, the study of saccade kinematics is affected by the low sampling rate. The GP3-HD is also able to capture psychological effects on pupil dilation in addition to the well-defined pupillary light reflex. Finally, moderate-to-strong correlations between physiological recordings and derived metrics of SC and HR between the GPB and the well-established BIOPAC MP160 support its validity. However, low amplitude of the SC signal obtained from the GPB may reduce sensitivity when separating phasic and tonic components. Similarly, data loss in pulse monitoring may pose difficulties for certain HR variability analyses.

Face memory and face perception in autism.

LAY ABSTRACT: It is well known that some people with autism have difficulties recognizing faces. It is generally thought that this is not because autistic individuals cannot perceive faces, but because autistic individuals have greater problems than people without autism in remembering faces. Here, we worked with a group of autistic adults and a group of non-autistic adults to test their ability to perceive and remember faces. We also asked each person to report any difficulties that they have with recognizing faces in everyday life. We find that, as a group, people with autism have difficulties with both remembering and perceiving faces, and report more problems recognizing faces in everyday life. However, it is worth noting that we observed a wide range of scores in the group of people with autism, with some autistic participants scoring as well as the group of people without autism.