A threat-detection advantage in those with autism spectrum disorders

Attention for Emotion-How Young Adults With Neurodevelopmental Disorders Look at Facial Expressions of Affect

While Autism Spectrum Disorder (ASD), Attention-Deficit/Hyperactivity Disorder (ADHD) and Schizophrenia (SCZ) differ in many clinically relevant features such as symptomatology and course, they may also share genetic underpinnings, affective problems, deviancies in social interactions, and are all characterized by some kind of cognitive impairment. This situation calls for a joint investigation of the specifics of cognitive (dys-)functions of the three disorders. Such endeavor should focus, among other domains, on the inter-section of processing cognitive, affective and social information that is crucial in effective real-life interactions and can be accomplished when attentional preferences for human facial expressions of emotions is studied. To that end, attention to facial expressions of basic emotions was examined in young adults with ASD, ADHD, or SCZ in the present study. The three clinical groups were compared with an age-matched group of typically-developing participants (TD) during the free contemplation of five different facial emotions presented simultaneously, by varying identities, through the registration of eye movements. We showed, that dwell times and fixation counts differed for the different emotions in TD and in a highly similar way in ADHD. Patients with ASD differed from TD by showing a stronger differentiation between emotions and partially different attentional preferences. In contrast, the SCZ group showed an overall more restricted scanning behavior and a lack of differentiation between emotions. The ADHD group, showed an emotion-specific gazing pattern that was highly similar to that of controls. Thus, by analyzing eye movements, we were able to differentiate three different viewing patterns that allowed us to distinguish between the three clinical groups. This outcome suggests that attention for emotion may not tap into common pathophysiological processes and argues for a multi-dimensional approach to the grouping of disorders with neurodevelopmental etiology.

Atypical development of emotional face processing networks in autism spectrum disorder from childhood through to adulthood

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MEG connectivity to emotional faces in ASD and typical controls 6–39 years of age was investigated.

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Distinct age-related changes in connectivity were observed in the groups to happy and angry faces.

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Age-related between-group differences in functional connectivity were found in gamma band.

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Emotion-specific age-related between-group differences were seen in beta.

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Findings highlight specific neurodevelopmental trajectories to emotional faces in ASD vs. TD.

Impairments in social functioning are hallmarks of autism spectrum disorder (ASD) and atypical functional connectivity may underlie these difficulties. Emotion processing networks typically undergo protracted maturational changes, however, those with ASD show either hyper- or hypo-connectivity with little consensus on the functional connectivity underpinning emotion processing. Magnetoencephalography was used to investigate age-related changes in whole-brain functional connectivity of eight regions of interest during happy and angry face processing in 190 children, adolescents and adults (6–39 years) with and without ASD. Findings revealed age-related changes from child- through to mid-adulthood in functional connectivity in controls and in ASD in theta, as well as age-related between-group differences across emotions, with connectivity decreasing in ASD, but increasing for controls, in gamma. Greater connectivity to angry faces was observed across groups in gamma. Emotion-specific age-related between-group differences in beta were also found, that showed opposite trends with age for happy and angry in ASD. Our results establish altered, frequency-specific developmental trajectories of functional connectivity in ASD, across distributed networks and a broad age range, which may finally help explain the heterogeneity in the literature.

The influence of emotional face distractors on attentional orienting in Chinese children with autism spectrum disorder

The current study examined how emotional faces impact on attentional control at both involuntary and voluntary levels in children with and without autism spectrum disorder (ASD). A non-face single target was either presented in isolation or synchronously with emotional face distractors namely angry, happy and neutral faces. ASD and typically developing children made more erroneous saccades towards emotional distractors relative to neutral distractors in parafoveal and peripheral conditions. Remote distractor effects were observed on saccade latency in both groups regardless of distractor type, whereby time taken to initiate an eye movement to the target was longest in central distractor conditions, followed by parafoveal and peripheral distractor conditions. The remote distractor effect was greater for angry faces compared to happy faces in the ASD group. Proportions of failed disengagement trials from central distractors, for the first saccade, were higher in the angry distractor condition compared with the other two distractor conditions in ASD, and this effect was absent for the typical group. Eye movement results suggest difficulties in disengaging from fixated angry faces in ASD. Atypical disengagement from angry faces at the voluntary level could have consequences for the development of higher-level socio-communicative skills in ASD.

Attentional Patterns to Emotional Faces Versus Scenes in Children with Autism Spectrum Disorders

Previous research has shown attentional biases in children with autism spectrum disorders (ASD) when processing distressing information. This study examined these attentional patterns as a function of the type of stimulus (scenes and faces) and the stimulus valence (happy, sad, threatening, neutral) using a within-subject design. A dot-probe was applied to ASD (n = 24) and typically developing (TD) children (n = 24). Results showed no differences between the groups for happy and sad stimuli. Critically, ASD children showed an attentional bias toward threatening scenes but away from threatening faces. Thus, the type of stimuli modulated the direction of attentional biases to distressing information in ASD children. These results are discussed in the framework of current theories on cognitive and emotional processing in ASD.

Autistic traits and social anxiety predict differential performance on social cognitive tasks in typically developing young adults

The current work examined the unique contribution that autistic traits and social anxiety have on tasks examining attention and emotion processing. In Study 1, 119 typically-developing college students completed a flanker task assessing the control of attention to target faces and away from distracting faces during emotion identification. In Study 2, 208 typically-developing college students performed a visual search task which required identification of whether a series of 8 or 16 emotional faces depicted the same or different emotions. Participants with more self-reported autistic traits performed more slowly on the flanker task in Study 1 than those with fewer autistic traits when stimuli depicted complex emotions. In Study 2, participants higher in social anxiety performed less accurately on trials showing all complex faces; participants with autistic traits showed no differences. These studies suggest that traits related to autism and to social anxiety differentially impact social cognitive processing.

Young Adults with Autism Spectrum Disorder Show Early Atypical Neural Activity during Emotional Face Processing

Social cognition is impaired in autism spectrum disorder (ASD). The ability to perceive and interpret affect is integral to successful social functioning and has an extended developmental course. However, the neural mechanisms underlying emotional face processing in ASD are unclear. Using magnetoencephalography (MEG), the present study explored neural activation during implicit emotional face processing in young adults with and without ASD. Twenty-six young adults with ASD and 26 healthy controls were recruited. Participants indicated the location of a scrambled pattern (target) that was presented alongside a happy or angry face. Emotion-related activation sources for each emotion were estimated using the Empirical Bayes Beamformer (p_corr ≤ 0.001) in Statistical Parametric Mapping 12 (SPM12). Emotional faces elicited elevated fusiform, amygdala and anterior insula and reduced anterior cingulate cortex (ACC) activity in adults with ASD relative to controls. Within group comparisons revealed that angry vs. happy faces elicited distinct neural activity in typically developing adults; there was no distinction in young adults with ASD. Our data suggest difficulties in affect processing in ASD reflect atypical recruitment of traditional emotional processing areas. These early differences may contribute to difficulties in deriving social reward from faces, ascribing salience to faces, and an immature threat processing system, which collectively could result in deficits in emotional face processing.

Impaired detection and differentiation of briefly presented facial emotions in adults with high-functioning autism and asperger syndrome

Although deficits in the recognition of emotional facial expressions are considered a hallmark of autism spectrum disorder (ASD), characterization of abnormalities in the differentiation of emotional expressions (e.g., sad vs. angry) has been rather inconsistent, especially in adults without intellectual impairments who may compensate for their deficits. In addition, previous research neglected the ability to detect emotional expressions (e.g., angry vs. neutral). The present study used a backward masking paradigm to investigate, a) the detection of emotional expressions, and b) the differentiation of emotional expressions in adults diagnosed with high functioning autism or Asperger syndrome (n = 23) compared to neurotypical controls (n = 25). Compensatory strategies were prevented by shortening the stimulus presentation time (33, 67, and 100 ms). In general, participants with ASD were significantly less accurate in detecting and differentiating emotional expressions compared to the control group. In the emotion differentiation task, individuals with ASD profited significantly less from an increase in presentation time. These results reinforce theoretical models that individuals with ASD have deficits in emotion recognition under time constraints. Furthermore, first evidence was provided that emotion detection and emotion differentiation are impaired in ASD.

Impaired detection of happy facial expressions in autism

The detection of emotional facial expressions plays an indispensable role in social interaction. Psychological studies have shown that typically developing (TD) individuals more rapidly detect emotional expressions than neutral expressions. However, it remains unclear whether individuals with autistic phenotypes, such as autism spectrum disorder (ASD) and high levels of autistic traits (ATs), are impaired in this ability. We examined this by comparing TD and ASD individuals in Experiment 1 and individuals with low and high ATs in Experiment 2 using the visual search paradigm. Participants detected normal facial expressions of anger and happiness and their anti-expressions within crowds of neutral expressions. In Experiment 1, reaction times were shorter for normal angry expressions than for anti-expressions in both TD and ASD groups. This was also the case for normal happy expressions vs. anti-expressions in the TD group but not in the ASD group. Similarly, in Experiment 2, the detection of normal vs. anti-expressions was faster for angry expressions in both groups and for happy expressions in the low, but not high, ATs group. These results suggest that the detection of happy facial expressions is impaired in individuals with ASD and high ATs, which may contribute to their difficulty in creating and maintaining affiliative social relationships.

Early Predictors of Impaired Social Functioning in Male Rhesus Macaques (Macaca mulatta)

Autism spectrum disorder (ASD) is characterized by social cognition impairments but its basic disease mechanisms remain poorly understood. Progress has been impeded by the absence of animal models that manifest behavioral phenotypes relevant to ASD. Rhesus monkeys are an ideal model organism to address this barrier to progress. Like humans, rhesus monkeys are highly social, possess complex social cognition abilities, and exhibit pronounced individual differences in social functioning. Moreover, we have previously shown that Low-Social (LS) vs. High-Social (HS) adult male monkeys exhibit lower social motivation and poorer social skills. It is not known, however, when these social deficits first emerge. The goals of this study were to test whether juvenile LS and HS monkeys differed as infants in their ability to process social information, and whether infant social abilities predicted later social classification (i.e., LS vs. HS), in order to facilitate earlier identification of monkeys at risk for poor social outcomes. Social classification was determined for N = 25 LS and N = 25 HS male monkeys that were 1-4 years of age. As part of a colony-wide assessment, these monkeys had previously undergone, as infants, tests of face recognition memory and the ability to respond appropriately to conspecific social signals. Monkeys later identified as LS vs. HS showed impairments in recognizing familiar vs. novel faces and in the species-typical adaptive ability to gaze avert to scenes of conspecific aggression. Additionally, multivariate logistic regression using infant social ability measures perfectly predicted later social classification of all N = 50 monkeys. These findings suggest that an early capacity to process important social information may account for differences in rhesus monkeys' motivation and competence to establish and maintain social relationships later in life. Further development of this model will facilitate identification of novel biological targets for intervention to improve social outcomes in at-risk young monkeys.

Salivary cortisol and behavioral response to social evaluative threat in adolescents with autism spectrum disorder

Autism Spectrum Disorder (ASD) is a neurodevelopmental disorder characterized by deficits in social behavior. One possible explanation for social communication deficits in ASD could be differences in biological systems that support responses to environmental stimuli. If so, it is unclear if differences in the arousal response to social stimuli in ASD are due to reduced interest in social information, or to an increased stress response. The hypothalamic pituitary adrenal axis facilitates arousal and the stress response to sensory input, including social stimuli. Previous research shows blunted cortisol response to social evaluative threat in children with ASD. The majority of prior work has focused on children with ASD, but adolescents with ASD are understudied. The adolescent period is of interest, as this developmental epoch is associated with increased salience of social evaluative threat in typically developing (TD) populations. In this study, we employed the Trier Social Stress Test (TSST), a laboratory paradigm that involves exposure to social evaluative threat, to study the cortisol and behavioral response to social evaluative threat in ASD and TD adolescents. Salivary cortisol data were collected at six time points before and after the TSST. Behavioral data were collected using video recordings of the TSST, which were then operationalized and coded. Paired sample t-tests were used to calculate within-group cortisol response to the TSST. Cortisol significantly increased in response to the TSST in the TD group but not the ASD group. The TD group showed a trend for more self-soothing behaviors during the stressor than the ASD group. The lack of a cortisol response to the TSST in the ASD group suggests that the TSST is not interpreted as stressful or salient for ASD adolescents. Autism Res 2017, 10: 346-358. © 2016 International Society for Autism Research, Wiley Periodicals, Inc.

Threatening faces fail to guide attention for adults with autistic-like traits

Individuals diagnosed with autistic spectrum conditions often show deficits in processing emotional faces relative to neurotypical peers. However, little is known about whether similar deficits exist in neurotypical individuals who show high-levels of autistic-like traits. To address this question, we compared performance on an attentional blink task in a large sample of adults who showed low- or high-levels of autistic-like traits on the Autism Spectrum Quotient. We found that threatening faces inserted as the second target in a rapid serial visual presentation were identified more accurately among individuals with low- compared to high-levels of autistic-like traits. This is the first study to show that attentional blink abnormalities seen in autism extend to the neurotypical population with autistic-like traits, adding to the growing body of research suggesting that autistic-related patterns of behaviors extend into a subset of the neurotypical population. Autism Res 2017, 10: 311-320. © 2016 International Society for Autism Research, Wiley Periodicals, Inc.

Exploring factors related to the anger superiority effect in children with Autism Spectrum Disorder

Despite face and emotion recognition deficits, individuals with Autism Spectrum Disorder (ASD) appear to experience the anger superiority effect, where an angry face in a crowd is detected faster than a neutral face. This study extended past research to examine the impacts of ecologically valid photographic stimuli, gender and anxiety symptoms on the anger superiority effect in children with and without ASD. Participants were 81, 7-12year old children, 42 with ASD matched on age, gender and perceptual IQ to 39 typically developing (TYP) children. The photographic stimuli did not impact on task performance in ASD with both groups exhibiting the anger superiority effect. There were no gender differences and no associations with anxiety. Age was associated with the effect in the TYP but not ASD group. These findings confirm a robust effect of speeded detection of threat in ASD which does not appear to be confounded by gender or anxiety, but may have different underlying age-associated mechanisms.

Reactive aggression among children with and without autism spectrum disorder

Twenty-seven boys and eight girls with ASD and thirty-five controls matched for gender, age and total score intelligence were studied to ascertain whether boys and girls with ASD display stronger reactive aggression than boys and girls without ASD. Participants performed a computerized version of the Pulkkinen aggression machine that examines the intensity of reactive aggression against attackers of varying gender and age. Relative to the control group boys, the boys with ASD reacted with more serious forms of aggression when subjected to mild aggressive attacks and did not consider a child attacker's opposite sex an inhibitory factor. The girls with ASD, on the other hand, reacted less aggressively than the girls without ASD. According to the results boys with ASD may not follow the typical development in cognitive regulation of reactive aggression.

Gaze Behavior of Children with ASD toward Pictures of Facial Expressions

Atypical gaze behavior in response to a face has been well documented in individuals with autism spectrum disorders (ASDs). Children with ASD appear to differ from typically developing (TD) children in gaze behavior for spoken and dynamic face stimuli but not for nonspeaking, static face stimuli. Furthermore, children with ASD and TD children show a difference in their gaze behavior for certain expressions. However, few studies have examined the relationship between autism severity and gaze behavior toward certain facial expressions. The present study replicated and extended previous studies by examining gaze behavior towards pictures of facial expressions. We presented ASD and TD children with pictures of surprised, happy, neutral, angry, and sad facial expressions. Autism severity was assessed using the Childhood Autism Rating Scale (CARS). The results showed that there was no group difference in gaze behavior when looking at pictures of facial expressions. Conversely, the children with ASD who had more severe autistic symptomatology had a tendency to gaze at angry facial expressions for a shorter duration in comparison to other facial expressions. These findings suggest that autism severity should be considered when examining atypical responses to certain facial expressions.

Attentional allocation of autism spectrum disorder individuals: Searching for a Face-in-the-Crowd

A study is reported which tests the proposition that faces capture the attention of those with autism spectrum disorders less than a typical population. A visual search task based on the Face-in-the-Crowd paradigm was used to examine the attentional allocation of autism spectrum disorder adults for faces. Participants were required to search for discrepant target images from within 9-image arrays. Both participants with autism spectrum disorder and control participants demonstrated speeded identification of faces compared to non-face objects. This indicates that when attention is under conscious control, both autism spectrum disorder and typically developing comparison adults show an attentional bias for faces, which contrasts with previous research which found an absence of an attentional bias for faces in autism spectrum disorder. Theoretical implications of this differentiation are discussed.

Absence of predispositional attentional sensitivity to angry faces in children with autism spectrum disorders

A rapid allocation of attention towards threatening stimuli in the environment is crucial for survival. Angry facial expressions act as threatening stimuli, and capture humans' attention more rapidly than emotionally positive facial expressions - a phenomenon known as the Anger Superiority Effect (ASE). Despite atypical emotional processing, adults with Autism Spectrum Disorders (ASD) have been reported to show ASE similar to typically developed (TD) individuals. One important question is whether the basic process for ASE is intact in individuals with ASD or whether instead they acquire an alternative process that enables ASE. To address this question, we tested the prevalence of ASE in young children with and without ASD using a face-in-the-crowd task. ASE was clearly observed in TD children, whereas ASD children did not show the effect. In contrast to previous reports of ASE in adults or relatively older children with ASD, our results suggest that in ASD basic predispositional mechanisms to allocate attention quickly towards angry faces are not preserved.

The influences of face inversion and facial expression on sensitivity to eye contact in high-functioning adults with autism spectrum disorders

We examined the influences of face inversion and facial expression on sensitivity to eye contact in high-functioning adults with and without an autism spectrum disorder (ASD). Participants judged the direction of gaze of angry, fearful, and neutral faces. In the typical group only, the range of directions of gaze leading to the perception of eye contact (the cone of gaze) was narrower for upright than inverted faces. In both groups, the cone of gaze was wider for angry faces than for fearful or neutral faces. These results suggest that in high-functioning adults with ASD, the perception of eye contact is not tuned to be finer for upright than inverted faces, but that information is nevertheless integrated across expression and gaze direction.

Preliminary evidence that different mechanisms underlie the anger superiority effect in children with and without Autism Spectrum Disorders

Previous studies have demonstrated that angry faces capture humans' attention more rapidly than emotionally positive faces. This phenomenon is referred to as the anger superiority effect (ASE). Despite atypical emotional processing, adults and children with Autism Spectrum Disorders (ASD) have been reported to show ASE as well as typically developed (TD) individuals. So far, however, few studies have clarified whether or not the mechanisms underlying ASE are the same for both TD and ASD individuals. Here, we tested how TD and ASD children process schematic emotional faces during detection by employing a recognition task in combination with a face-in-the-crowd task. Results of the face-in-the-crowd task revealed the prevalence of ASE both in TD and ASD children. However, the results of the recognition task revealed group differences: In TD children, detection of angry faces required more configural face processing and disrupted the processing of local features. In ASD children, on the other hand, it required more feature-based processing rather than configural processing. Despite the small sample sizes, these findings provide preliminary evidence that children with ASD, in contrast to TD children, show quick detection of angry faces by extracting local features in faces.

Explicit recognition of emotional facial expressions is shaped by expertise: evidence from professional actors

Can reading others' emotional states be shaped by expertise? We assessed processing of emotional facial expressions in professional actors trained either to voluntary activate mimicry to reproduce character's emotions (as foreseen by the "Mimic Method"), or to infer others' inner states from reading the emotional context (as foreseen by "Stanislavski Method"). In explicit recognition of facial expressions (Experiment 1), the two experimental groups differed from each other and from a control group with no acting experience: the Mimic group was more accurate, whereas the Stanislavski group was slower. Neither acting experience, instead, influenced implicit processing of emotional faces (Experiment 2). We argue that expertise can selectively influence explicit recognition of others' facial expressions, depending on the kind of "emotional expertise".

Monoamine oxidase A and A/B knockout mice display autistic-like features

Converging lines of evidence show that a sizable subset of autism-spectrum disorders (ASDs) is characterized by increased blood levels of serotonin (5-hydroxytryptamine, 5-HT), yet the mechanistic link between these two phenomena remains unclear. The enzymatic degradation of brain 5-HT is mainly mediated by monoamine oxidase (MAO)A and, in the absence of this enzyme, by its cognate isoenzyme MAOB. MAOA and A/B knockout (KO) mice display high 5-HT levels, particularly during early developmental stages. Here we show that both mutant lines exhibit numerous behavioural hallmarks of ASDs, such as social and communication impairments, perseverative and stereotypical responses, behavioural inflexibility, as well as subtle tactile and motor deficits. Furthermore, both MAOA and A/B KO mice displayed neuropathological alterations reminiscent of typical ASD features, including reduced thickness of the corpus callosum, increased dendritic arborization of pyramidal neurons in the prefrontal cortex and disrupted microarchitecture of the cerebellum. The severity of repetitive responses and neuropathological aberrances was generally greater in MAOA/B KO animals. These findings suggest that the neurochemical imbalances induced by MAOA deficiency (either by itself or in conjunction with lack of MAOB) may result in an array of abnormalities similar to those observed in ASDs. Thus, MAOA and A/B KO mice may afford valuable models to help elucidate the neurobiological bases of these disorders and related neurodevelopmental problems.

Reduced sensitivity to emotional facial expressions in borderline personality disorder: effects of emotional valence and intensity

A heightened sensitivity towards negative emotional stimuli has been described for Borderline Personality Disorder (BPD). We investigated whether a faster and more accurate detection of negatively valent information in BPD can be confirmed by means of a visual search task which required subjects to detect a face with an incongruent emotional expression within a crowd of neutral faces. Twenty eight BPD patients and 28 nonpatients were asked to indicate whether a set of schematic neutral faces (3 × 3, 4 × 4 matrices) contained a happy or an angry face. Besides valence, the intensity of the target's emotion was varied in two steps. BPD patients and nonpatients both demonstrated an anger-superiority effect. However, no higher sensitivity towards negative stimuli was observed in BPD compared to nonpatients. BPD patients seem to rely to a stronger extent on controlled, i.e., serial, attention demanding processes when searching more subtle social-emotional information with positive valence.

The Interplay between Emotion and Cognition in Autism Spectrum Disorder: Implications for Developmental Theory

Autism Spectrum Disorder (ASD) is a neurodevelopmental disorder that is clinically defined by abnormalities in reciprocal social and communicative behaviors and an inflexible adherence to routinised patterns of thought and behavior. Laboratory studies repeatedly demonstrate that autistic individuals experience difficulties in recognizing and understanding the emotional expressions of others and naturalistic observations show that they use such expressions infrequently and inappropriately to regulate social exchanges. Dominant theories attribute this facet of the ASD phenotype to abnormalities in a social brain network that mediates social-motivational and social-cognitive processes such as face processing, mental state understanding, and empathy. Such theories imply that only emotion related processes relevant to social cognition are compromised in ASD but accumulating evidence suggests that the disorder may be characterized by more widespread anomalies in the domain of emotions. In this review I summarize the relevant literature and argue that the social-emotional characteristics of ASD may be better understood in terms of a disruption in the domain-general interplay between emotion and cognition. More specifically I will suggest that ASD is the developmental consequence of early emerging anomalies in how emotional responses to the environment modulate a wide range of cognitive processes including those that are relevant to navigating the social world.

Verbal ability, social stress, and anxiety in children with autistic disorder

The aims of this study were to evaluate the physiological stress and anxiety responses in children with autism following completion of a standardized, social-evaluative stressor (Trier Social Stress Test-Child version), document the relationship between verbal ability, stress, and anxiety, and determine the association between stress and anxiety in children with autism and typical development. Results demonstrated the Trier Social Stress Test-Child version to be a benign stressor for children with autism. Lower verbal ability in children with autism did not predict salivary cortisol or anxiety responses. There was a lack of association between stress and anxiety for both groups, highlighting the importance of considering these terms as separate constructs. Clinical implications and the limited utility of the Trier Social Stress Test-Child version in evaluating psychosocial stress in autism are discussed.

Just another face in the crowd: evidence for decreased detection of angry faces in children with Williams syndrome

The detection of social threat is crucial for adaptive behaviour. Previous studies have shown that angry faces capture attention and are processed more efficiently than happy faces. While this anger superiority effect has been found in typical and atypical development, it is unknown whether it exists in individuals with Williams syndrome (WS), who show reduced social fear and atypical sociability. In this study, children with WS searched for angry or happy target faces surrounded by 2, 5 or 8 distracters (happy or angry faces, respectively). Performance was compared to that of mental age-matched controls. Results revealed no group differences for happy faces, however for angry faces, the WS, but not the control group, showed a significant performance decrease for the 8-distracters condition, indicating the absence of an anger superiority effect, in good agreement with evidence for abnormal structure and function in brain areas for social threat processing in WS.

Update on autism: a review of 1300 reports published in 2008

This publication, by reviewing 1300 studies published on autism in 2008, represents an update on this topic. Results include possible parental influences, maternal conditions, and studies on genes and chromosomes. Possible etiological factors involve the "extreme male brain," defects in the mirror neuron system, vaccines, underconnectivity, disorders of central coherence, and many other more specific etiologies. Assessments or tests for autism are also reviewed. Characteristics of autistic individuals include repetitive behavior, language disorders, sleep disturbances, social problems, joint attention disorders, seizures, allergic reactions, and various behavioral changes. Cognitive changes involve IQ, reasoning, and verbal and language disorders. The savant syndrome is a fascinating phenomenon, at times seen in autistic individuals. Neurophysiological and neuroanatomical changes are also reviewed, as are comorbid conditions. Finally, treatment involves various medications including risperidone, ziprasidone, and antipsychotic drugs, as well as different procedures such as magnetic stimulation, acupuncture, and hyperbaric oxygen therapy. As mentioned in the 2007 survey, nearly every conceivable problem that a child can have may be found in these unfortunate children and nearly every conceivable etiology has been mentioned to account for this serious disorder.