Intact emotion facilitation for nonsocial stimuli in autism: is amygdala impairment in autism specific for social information?

Are autistic traits associated with a social-emotional memory bias?

Autistic traits are associated with differential processing of emotional and social cues. By contrast little is known about the relationship of autistic traits to socio-emotional memory, though research suggests an integral relationship between episodic memory processes and psychosocial well-being. Using an experimental paradigm, we tested if autistic traits moderate the effects of negative emotion and social cues on episodic memory (i.e. memory for past events). Young adults (N = 706) with varied levels of self-reported autistic traits (24% in clinical range) encoded images stratified by emotion (negative, neutral) and social cues (social, non-social) alongside a neutral object. After 24 h, item memory for images and associative memory for objects was tested. For item memory, after controlling for anxiety, a small effect emerged whereby a memory-enhancing effect of social cues was reduced as autistic traits increased. For associative memory, memory for pairings between neutral, but not negative, images reduced as autistic traits increased. Results suggest autistic traits are associated with reduced ability to bind neutral items together in memory, potentially impeding nuanced appraisals of past experience. This bias toward more negative, less nuanced memories of past experience may represent a cognitive vulnerability to social and mental health challenges commonly associated with autistic traits and a potential intervention target.

An exploration of the impact of contextual information on the emotion recognition ability of autistic adults

Studies of non‐autistic individuals and people with an intellectual disability show that contextual information impacts positively on emotion recognition ability, however, this area is not well researched with autistic adults. We investigated this using a static emotion recognition task. Participants completed an emotion recognition task in person or online. In total, 46 autistic participants and 379 non‐autistic participants completed the task. A linear mixed model showed that autistic adults had significantly lower accuracy when identifying emotions across all contexts, compared to control participants, even when contextual information was present. No significant effect of context was found in either group, nor was gender shown to be an influential variable. A supplementary analysis showed that higher scores on the Autism‐Spectrum Quotient led to lower scores on the emotion recognition task; no effect of context was found here either. This research adds to the limited work investigating the influence of contextual factors in emotion recognition in autistic adults. Overall, it shows that context may not aid emotion recognition in this group in the same way as it does for non‐autistic individuals.

The Role of Decision-Making in Psychological Wellbeing and Risky Behaviours in Autistic Adolescents Without ADHD: Longitudinal Evidence from the UK Millennium Cohort Study

This study examined the development of decision-making and its association with psychological wellbeing and risky behaviours in adolescents with and without autism. Participants included 270 autistic and 9,713 typically developing adolescents. In both samples, those with a diagnosis of attention-deficit/hyperactivity disorder (ADHD) were excluded. Data came from the Millennium Cohort Study, a nationally representative population-based birth cohort. Decision-making was assessed using the Cambridge Gambling Task at ages 11 and 14. Psychological wellbeing (happiness, self-esteem, depressive symptoms and self-harm) and risky/antisocial behaviours were self-reported at age 14. After adjusting for sex, cognitive ability, spatial working memory, socioeconomic status and pubertal status, autistic adolescents showed comparable quality of decision-making to that of their peers at both ages but also a more deliberative decision-making style as they aged. Only in autistic adolescents was this decision-making style associated with positive outcomes.

Brief Report: Emotional Picture and Language Processing in Adults with Autism Spectrum Disorder

There is currently limited research and a lack of consensus on emotional processing impairments among adults with autism spectrum disorder (ASD). The present pilot study sought to characterize the extent to which adults with ASD are impaired in processing emotions in both words and pictures. Ten adults with ASD rated word and picture stimuli on emotional valence and arousal. Their ratings were compared to normative data for both stimuli sets using item-level correlations. Adults with ASD rank-ordered stimuli similarly to typically developing individuals, demonstrating relatively typical understanding of emotional words and pictures. However, they used a narrower range of the scales which suggests more subtle impairments affecting emotion-processing. Future directions arising from the findings of this pilot study are discussed.

Non-Clinical Autistic Traits Correlate With Social and Ethical but Not With Financial and Recreational Risk-Taking

Previous research into uncertain and risky decision-making in autism spectrum disorder (ASD) has been inconclusive, with some studies reporting less uncertain and risky decisions by persons with ASD compared to neurotypicals, but other studies failing to find such effects. A possible explanation for these inconsistent findings is that aberrant decision-making in ASD is domain-specific, and only manifests itself in domains related to autism symptomatology. The present study examines this premise by correlating self-reported autistic traits to individuals' intention to engage in risky behaviours, their perception of how risky these behaviours are, and the amount of benefit they expect to obtain from engaging in them; all for five separate domains of decision-making: social, ethical, recreational, health/safety, and financial. In line with the hypotheses, persons with higher autistic traits reported reduced intention to engage in risky social behaviours and increased intention to engage in risky ethical behaviours. Furthermore, a positive correlation was found between autistic traits and risk perception in the social domain, indicating that persons with higher autistic traits perceive social behaviours as riskier than do persons with lower autistic traits. Correlations between autistic traits and individuals' intention to engage in risky recreational and financial behaviours were small, and supported the null hypothesis (as shown by Bayes Factors). Given that most studies on uncertain and risky decision-making take place in a financial context, the present results could explain previous inconsistent findings on decision-making in ASD. Therefore, future studies should also examine decision-making outside the financial realm.

Exploring the neurocognitive basis of episodic recollection in autism

Increasing evidence indicates that the subjective experience of recollection is diminished in autism spectrum disorder (ASD) compared to neurotypical individuals. The neurocognitive basis of this difference in how past events are re-experienced has been debated and various theoretical accounts have been proposed to date. Although each existing theory may capture particular features of memory in ASD, recent research questions whether any of these explanations are alone sufficient or indeed fully supported. This review first briefly considers the cognitive neuroscience of how episodic recollection operates in the neurotypical population, informing predictions about the encoding and retrieval mechanisms that might function atypically in ASD. We then review existing research on recollection in ASD, which has often not distinguished between different theoretical explanations. Recent evidence suggests a distinct difficulty engaging recollective retrieval processes, specifically the ability to consciously reconstruct and monitor a past experience, which is likely underpinned by altered functional interactions between neurocognitive systems rather than brain region-specific or process-specific dysfunction. This integrative approach serves to highlight how memory research in ASD may enhance our understanding of memory processes and networks in the typical brain. We make suggestions for future research that are important for further specifying the neurocognitive basis of episodic recollection in ASD and linking such difficulties to social developmental and educational outcomes.

Emotional false memory in autism spectrum disorder: More than spared

To advance what is known about how emotions affect memory in autism spectrum disorder (ASD), we examined emotional false memory for negative, positive, and neutrally valenced photographs comprising scripts of everyday events in a verbal IQ-case matched sample of youth ages 8-14 with ASD (N = 38) and typical development (TYP, N = 38). The groups exhibited many similarities. Their task performance during a recognition task including previously seen and unseen photographs was largely comparable. They evidenced high hit rates for previously viewed photographs, and low false alarm rates for lure photographs that were inconsistent with the scripts. Both ASD and TYP groups showed relatively higher false alarms for lure photographs depicting previously unseen causes of scenario outcomes (causal errors) compared to errors for script-consistent lure photographs that showed extra potentially related events (gap-filling errors). In both groups, task performance was associated with verbal working memory, but not attention deficit hyperactivity, anxiety, or depression symptoms. However, the ASD group made more causal and gap-filling errors on negative and positive, but not neutral, lures compared to TYP, indicating that viewing emotionally valenced stimuli made it harder to discriminate previously seen and unseen photographs. For the ASD group, task performance was associated with compulsive, ritualistic, and sameness behaviors and stereotypic and restricted interests. Findings suggest that the integration of cognition and emotion in ASD is altered and associated with the presence of repetitive behaviors. The impact of these results on the lives of individuals with ASD and implications for psychosocial interventions are discussed. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

Visual and Hedonic Perception of Food Stimuli in Children with Autism Spectrum Disorders and their Relationship to Food Neophobia

The present study examined whether children with autism spectrum disorder (ASD) and typically developing (TD) children differed in visual perception of food stimuli at both sensorimotor and affective levels. A potential link between visual perception and food neophobia was also investigated. To these aims, 11 children with ASD and 11 TD children were tested. Visual pictures of food were used, and food neophobia was assessed by the parents. Results revealed that children with ASD explored visually longer food stimuli than TD children. Complementary analyses revealed that whereas TD children explored more multiple-item dishes (vs. simple-item dishes), children with ASD explored all the dishes in a similar way. In addition, children with ASD gave more negative appreciation in general. Moreover, hedonic rating was negatively correlated with food neophobia scores in children with ASD, but not in TD children. In sum, we show here that children with ASD have more difficulty than TD children in liking a food when presented visually. Our findings also suggest that a prominent factor that needs to be considered is time management during the food choice process. They also provide new ways of measuring and understanding food neophobia in children with ASD.

Effects of familiarization on odor hedonic responses and food choices in children with autism spectrum disorders

This study assessed whether olfactory familiarization can render food odors more pleasant, and consequently food more attractive, to children with autism spectrum disorder. Participants were first presented with a series of food odors (session 1). Then, they were familiarized on four occasions (time window: 5 weeks) with one of the two most neutral odors (the other neutral odor was used as control) (session 2). In session 3, participants smelled the entire series of odors again. Both verbal and facial responses were compared from session 1 to session 3. After session 3, the children were presented with two identical foods (one containing the familiarized odor and one the control odor) and were asked to choose between these foods. Results revealed (1) a specific increase in positive emotions for the familiarized odor and (2) that 68% of the children chose the food associated with the "familiarized odor" (children who chose the "familiarized odor" food exhibited significantly more sensory particularities). These findings suggest that it is possible to modulate olfactory emotions and expand the dietary repertoire of children with autism spectrum disorder. Application of this paradigm may enable innovative prospects for food education in autism.

A functional neuroimaging study of fusiform response to restricted interests in children and adolescents with autism spectrum disorder

Background

While autism spectrum disorder (ASD) is characterized by both social communication deficits and restricted and repetitive patterns of behavior and interest, literature examining possible neural bases of the latter class of symptoms is limited. The fusiform face area (FFA) is a region in the ventral temporal cortex that not only shows preferential responsiveness to faces but also responds to non-face objects of visual expertise. Because restricted interests in ASD are accompanied by high levels of visual expertise, the objective of this study was to determine the extent to which this region responds to images related to restricted interests in individuals with ASD, compared to individuals without ASD who have a strong hobby or interest.

Methods

Children and adolescents with and without ASD with hobbies or interests that consumed a pre-determined minimum amount of time were identified, and the intensity, frequency, and degree of interference of these interests were quantified. Each participant underwent functional magnetic resonance imaging (fMRI) while viewing images related to their personal restricted interests (in the ASD group) or strong interest or hobby (in the comparison group). A generalized linear model was used to compare the intensity and spatial extent of fusiform gyrus response between groups, controlling for the appearance of faces in the stimuli.

Results

Images related to interests and expertise elicited response in FFA in both ASD and typically developing individuals, but this response was more robust in ASD.

Conclusions

These findings add neurobiological support to behavioral observations that restricted interests are associated with enhanced visual expertise in ASD, above and beyond what would be expected for simply a strong interest. Further, the results suggest that brain regions associated with social functioning may not be inherently less responsive in ASD, but rather may be recruited by different environmental stimuli. This study contributes to our understanding of the neural basis of restricted interests in ASD and may provide clues toward developing novel interventions.

Electronic supplementary material

The online version of this article (doi:10.1186/s11689-016-9149-6) contains supplementary material, which is available to authorized users.

Processing of emotion words by patients with autism spectrum disorders: evidence from reaction times and EEG

This study investigated processing of emotion words in autism spectrum disorders (ASD) using reaction times and event-related potentials (ERP). Adults with (n = 21) and without (n = 20) ASD performed a lexical decision task on emotion and neutral words while their brain activity was recorded. Both groups showed faster responses to emotion words compared to neutral, suggesting intact early processing of emotion in ASD. In the ERPs, the control group showed a typical late positive component (LPC) at 400-600 ms for emotion words compared to neutral, while the ASD group showed no LPC. The between-group difference in LPC amplitude was significant, suggesting that emotion words were processed differently by individuals with ASD, although their behavioral performance was similar to that of typical individuals.

Complexities of emotional responses to social and non-social affective stimuli in schizophrenia

BACKGROUND

Adaptive emotional responses are important in interpersonal relationships. We investigated self-reported emotional experience, physiological reactivity, and micro-facial expressivity in relation to the social nature of stimuli in individuals with schizophrenia (SZ).

METHOD

Galvanic skin response (GSR) and facial electromyography (fEMG) were recorded in medicated outpatients with SZ and demographically matched healthy controls (CO) while they viewed social and non-social images from the International Affective Pictures System. Participants rated the valence and arousal, and selected a label for experienced emotions. Symptom severity in the SZ and psychometric schizotypy in CO were assessed.

RESULTS

The two groups did not differ in their labeling of the emotions evoked by the stimuli, but individuals with SZ were more positive in their valence ratings. Although self-reported arousal was similar in both groups, mean GSR was greater in SZ, suggesting differential awareness, or calibration of internal states. Both groups reported social images to be more arousing than non-social images but their physiological responses to non-social vs. social images were different. Self-reported arousal to neutral social images was correlated with positive symptoms in SZ. Negative symptoms in SZ and disorganized schizotypy in CO were associated with reduced mean fEMG. Greater corrugator mean fEMG activity for positive images in SZ indicates valence-incongruent facial expressions.

CONCLUSION

The patterns of emotional responses differed between the two groups. While both groups were in broad agreement in self-reported arousal and emotion labels, their mean GSR, and fEMG correlates of emotion diverged in relation to the social nature of the stimuli and clinical measures. Importantly, these results suggest disrupted self awareness of internal states in SZ and underscore the complexities of emotion processing in health and disease.

Emotional language processing in autism spectrum disorders: a systematic review

In his first description of Autism Spectrum Disorders (ASD), Kanner emphasized emotional impairments by characterizing children with ASD as indifferent to other people, self-absorbed, emotionally cold, distanced, and retracted. Thereafter, emotional impairments became regarded as part of the social impairments of ASD, and research mostly focused on understanding how individuals with ASD recognize visual expressions of emotions from faces and body postures. However, it still remains unclear how emotions are processed outside of the visual domain. This systematic review aims to fill this gap by focusing on impairments of emotional language processing in ASD. We systematically searched PubMed for papers published between 1990 and 2013 using standardized search terms. Studies show that people with ASD are able to correctly classify emotional language stimuli as emotionally positive or negative. However, processing of emotional language stimuli in ASD is associated with atypical patterns of attention and memory performance, as well as abnormal physiological and neural activity. Particularly, younger children with ASD have difficulties in acquiring and developing emotional concepts, and avoid using these in discourse. These emotional language impairments were not consistently associated with age, IQ, or level of development of language skills. We discuss how emotional language impairments fit with existing cognitive theories of ASD, such as central coherence, executive dysfunction, and weak Theory of Mind. We conclude that emotional impairments in ASD may be broader than just a mere consequence of social impairments, and should receive more attention in future research.

Conflict adaptation and congruency sequence effects to social–emotional stimuli in individuals with autism spectrum disorders

Background:

The modification of performance following conflict can be measured using conflict adaptation tasks thought to measure the change in the allocation of cognitive resources in order to reduce conflict interference and improve performance. While previous studies have suggested atypical processing during nonsocial cognitive control tasks, conflict adaptation (i.e. congruency sequence effects) for social–emotional stimuli have not been previously studied in autism spectrum disorder.

Methods:

A total of 32 participants diagnosed with autism spectrum disorder and 27 typically developing matched controls completed an emotional Stroop conflict task that required the classification of facial affect while simultaneously ignoring an overlaid affective word.

Results:

Both groups showed behavioral evidence for emotional conflict adaptation based on response times and accuracy rates. However, the autism spectrum disorder group demonstrated a speed-accuracy trade-off manifested through significantly faster response times and decreased accuracy rates on trials containing conflict between the emotional face and the overlaid emotional word.

Conclusion:

Reduced selective attention toward socially relevant information may bias individuals with autism spectrum disorder toward more rapid processing and decision making even when conflict is present. Nonetheless, the loss of important information from the social stimuli reduces decision-making accuracy, negatively affecting the ability to adapt both cognitively and emotionally when conflict arises.

Physiological responses to social and nonsocial stimuli in neurotypical adults with high and low levels of autistic traits: implications for understanding nonsocial drive in autism spectrum disorders

Researchers have suggested that the two primary cognitive features of autism spectrum disorder (ASD), a drive toward nonsocial processing and a reduced drive toward social processing, may be unrelated to each other in the neurotypical (NT) population and may therefore require separate explanations. Drive toward types of processing may be related to physiological arousal to categories of stimuli, such as social (e.g., faces) or nonsocial (e.g., trains). This study investigated how autistic traits in an NT population might relate to differences in physiological responses to nonsocial compared with social stimuli. NT participants were recruited to examine these differences in those with high vs. low degrees of ASD traits. Forty-six participants (21 male, 25 female) completed the Autism Spectrum Quotient (AQ) to measure ASD traits before viewing a series of 24 images while skin conductance response (SCR) was recorded. Images included six nonsocial, six social, six face-like cartoons, and six nonsocial (relating to participants' personal interests). Analysis revealed that those with a higher AQ had significantly greater SCR arousal to nonsocial stimuli than those with a low AQ, and the higher the AQ, the greater the difference between SCR arousal to nonsocial and social stimuli. This is the first study to identify the relationship between AQ and physiological response to nonsocial stimuli, and a relationship between physiological response to both social and nonsocial stimuli, suggesting that physiological response may underlie the atypical drive toward nonsocial processing seen in ASD, and that at the physiological level at least the social and nonsocial in ASD may be related to one another.

A Two-Hit Model of Autism: Adolescence as the Second Hit

Adolescence brings dramatic changes in behavior and neural organization. Unfortunately, for some 30% of individuals with autism, there is marked decline in adaptive functioning during adolescence. We propose a two-hit model of autism. First, early perturbations in neural development function as a "first hit" that sets up a neural system that is "built to fail" in the face of a second hit. Second, the confluence of pubertal hormones, neural reorganization, and increasing social demands during adolescence provides the "second hit" that interferes with the ability to transition into adult social roles and levels of adaptive functioning. In support of this model, we review evidence about adolescent-specific neural and behavioral development in autism. We conclude with predictions and recommendations for empirical investigation about several domains in which developmental trajectories for individuals with autism may be uniquely deterred in adolescence.

Pten haploinsufficient mice show broad brain overgrowth but selective impairments in autism-relevant behavioral tests

Accelerated head and brain growth (macrocephaly) during development is a replicated biological finding in a subset of individuals with autism spectrum disorder (ASD). However, the relationship between brain overgrowth and the behavioral and cognitive symptoms of ASD is poorly understood. The PI3K-Akt-mTOR pathway regulates cellular growth; several genes encoding negative regulators of this pathway are ASD risk factors, including PTEN. Mutations in PTEN have been reported in individuals with ASD and macrocephaly. We report that brain overgrowth is widespread in Pten germline haploinsufficient (Pten(+/-)) mice, reflecting Pten mRNA expression in the developing brain. We then ask if broad brain overgrowth translates into general or specific effects on the development of behavior and cognition by testing Pten(+/-) mice using assays relevant to ASD and comorbidities. Deficits in social behavior were observed in both sexes. Males also showed abnormalities related to repetitive behavior and mood/anxiety. Females exhibited circadian activity and emotional learning phenotypes. Widespread brain overgrowth together with selective behavioral impairments in Pten(+/-) mice raises the possibility that most brain areas and constituent cell types adapt to an altered trajectory of growth with minimal impact on the behaviors tested in our battery; however, select areas/cell types relevant to social behavior are more vulnerable or less adaptable, thus resulting in social deficits. Probing dopaminergic neurons as a candidate vulnerable cell type, we found social behavioral impairments in mice with Pten conditionally inactivated in dopaminergic neurons that are consistent with the possibility that desynchronized growth in key cell types may contribute to ASD endophenotypes.

The amygdala and the relevance detection theory of autism: an evolutionary perspective

In the last few decades there has been increasing interest in the role of the amygdala in psychiatric disorders and, in particular, in its contribution to the socio-emotional impairments in autism spectrum disorders (ASDs). Given that the amygdala is a component structure of the "social brain," several theoretical explanations compatible with amygdala dysfunction have been proposed to account for socio-emotional impairments in ASDs, including abnormal eye contact, gaze monitoring, face processing, mental state understanding, and empathy. Nevertheless, many theoretical accounts, based on the Amygdala Theory of Autism, fail to elucidate the complex pattern of impairments observed in this population, which extends beyond the social domain. As posited by the Relevance Detector theory (Sander et al., 2003), the human amygdala is a critical component of a brain circuit involved in the appraisal of self-relevant events that include, but are not restricted to, social stimuli. Here, we propose that the behavioral and social-emotional features of ASDs may be better understood in terms of a disruption in a "Relevance Detector Network" affecting the processing of stimuli that are relevant for the organism's self-regulating functions. In the present review, we will first summarize the main literature supporting the involvement of the amygdala in socio-emotional disturbances in ASDs. Next, we will present a revised version of the Amygdala Relevance Detector hypothesis and we will show that this theoretical framework can provide a better understanding of the heterogeneity of the impairments and symptomatology of ASDs. Finally, we will discuss some predictions of our model, and suggest new directions in the investigation of the role of the amygdala within the more generally disrupted cortical connectivity framework as a model of neural organization of the autistic brain.

Reward-based decision making and electrodermal responding by young children with autism spectrum disorders during a gambling task

In this study, we explore reward-based decision making and electrodermal responding (EDR) among children with autism spectrum disorder (ASD) during a children's gambling task. In addition, we examine whether individual behavioral and EDR responses predict social communication, repetitive symptoms, parent reports of executive function, and behavioral challenges. The ability to form advantageous strategies for long-term gain is of interest for children with ASD, who exhibit both difficulty with executive function and atypical responses to reward. Twenty-one children ages 6-7 years with ASD and no intellectual disability, and 21 age- and IQ-matched typically developing children participated. Both groups exhibited a similar pattern of gambling selections, but children with ASD showed less knowledge of the reward contingencies of the decks after playing. In addition, although EDR was similar between groups in anticipation of selections, children with ASD exhibited greater EDR during feedback about rewards as the task progressed. Children with ASD who exhibited the greatest increases in EDR were more likely to exhibit repetitive symptoms, particularly rituals and the need for sameness, as well as internalizing behaviors and reduced executive function in other settings.

Modulation of attentional blink with emotional faces in typical development and in autism spectrum disorders

BACKGROUND

The attentional blink (AB) phenomenon was used to assess the effect of emotional information on early visual attention in typically developing (TD) children and children with autism spectrum disorders (ASD). The AB effect is the momentary perceptual unawareness that follows target identification in a rapid serial visual processing stream. It is abolished or reduced for emotional stimuli, indicating that emotional information has privileged access to early visual attention processes.

METHODS

We examined the AB effect for faces with neutral and angry facial expressions in 8- to 14-year-old children with and without an ASD diagnosis.

RESULTS

Children with ASD exhibited the same magnitude AB effect as TD children for both neutral and angry faces.

CONCLUSIONS

Early visual attention to emotional facial expressions was preserved in children with ASD.

Are emotion impairments unique to, universal, or specific in autism spectrum disorder? A comprehensive review

There is widespread belief that individuals with autism spectrum disorders (ASDs) are "emotionally detached" from others. This comprehensive review examines the empirical evidence for this assumption, addressing three critical questions: (1) Are emotion-processing impairments universal in ASD? (2) Are they specific, or can they be explained by deficits in other domains? (3) Is the emotion processing profile seen in ASD unique to these conditions? Upon review of the literature (over 200 studies), we conclude that: (1) emotion-processing impairments might not be universal in ASD, as suggested by variability across participants and across emotion-processing tasks; (2) emotion-processing impairments might not be specific to ASD, as domain-general processes appear to account for some of these impairments; and (3) the specific pattern of emotion-processing strengths and weaknesses observed in ASD, involving difficulties with processing social versus non-social, and complex versus simple emotional information (with impairments more consistently reported on implicit than explicit emotion-processing tasks), appears to be unique to ASD. The emotion-processing profile observed in ASD might be best understood as resulting from heterogeneous vulnerabilities in different components of an "emotional communication system" that, in typical development, emerges from the interplay between domain-general cognitive, social and affective processes.

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.

Feedback and reward processing in high-functioning autism

Individuals with high-functioning autism often display deficits in social interactions and high-level cognitive functions. Such deficits may be influenced by poor ability to process feedback and rewards. The feedback-related negativity (FRN) is an event-related potential (ERP) that is more negative following losses than gains. We examined FRN amplitude in 25 individuals with Autism Spectrum Disorder (ASD) and 25 age- and IQ-matched typically developing control participants who completed a guessing task with monetary loss/gain feedback. Both groups demonstrated a robust FRN that was more negative to loss trials than gain trials; however, groups did not differ in FRN amplitude as a function of gain or loss trials. N1 and P300 amplitudes did not differentiate groups. FRN amplitude was positively correlated with age in individuals with ASD, but not measures of intelligence, anxiety, behavioral inhibition, or autism severity. Given previous findings of reduced-amplitude error-related negativity (ERN) in ASD, we propose that individuals with ASD may process external, concrete, feedback similar to typically developing individuals, but have difficulty with internal, more abstract, regulation of performance.

Male predominance in autism: neuroendocrine influences on arousal and social anxiety

We offer a neurobiologic theory based on animal work that helps account for the conspicuous male predominance in autism spectrum disorders (ASD). In young male animals, testosterone (TST) binds to androgen receptors (AR) in brainstem neurons responsible for enhancing brain arousal. As a consequence, arousal-related neurotransmitters bombard the amygdala hypersensitized by TST acting though AR. Arousal-related inputs are known to prime amygdaloid mechanisms for fear and anxiety, with resultant social avoidance. We hypothesize that similar mechanisms contribute to autism's male predominance and to its defining impaired social skills. The theory rests on two key interacting factors: the molecular effects of TST in genetically vulnerable boys in combination with environmental stresses they experienced in utero, neonatally, or during the first years. We postulate that higher TST levels and, therefore, higher amounts of arousal-related inputs to the amygdala sensitize these genetically vulnerable male infants to very early stresses. In sharp contrast to boys, girls not only do not have high levels of TST-facilitated arousal-causing inputs to the amygdala but they also enjoy the protection afforded by estrogenic hormones, oxytocin, and the oxytocin receptor. This theory suggests that novel technologies applied to the molecular endocrinology of TST's actions through AR will offer new avenues of enquiry into ASD. Since the high male preponderance in autism is important yet understudied, we offer our theory, which is based on detailed neurobehavioral research with animals, to stimulate basic and clinical research in animals and humans and hopefully help develop novel more effective medical treatments for autism.

Reward circuitry function in autism spectrum disorders

Social interaction deficits and restricted repetitive behaviors and interests that characterize autism spectrum disorders (ASDs) may both reflect aberrant functioning of brain reward circuits. However, no neuroimaging study to date has investigated the integrity of reward circuits using an incentive delay paradigm in individuals with ASDs. In the present study, we used functional magnetic resonance imaging to assess blood-oxygen level-dependent activation during reward anticipation and outcomes in 15 participants with an ASD and 16 matched control participants. Brain activation was assessed during anticipation of and in response to monetary incentives and object image incentives previously shown to be visually salient for individuals with ASDs (e.g., trains, electronics). Participants with ASDs showed decreased nucleus accumbens activation during monetary anticipation and outcomes, but not during object anticipation or outcomes. Group × reward-type-interaction tests revealed robust interaction effects in bilateral nucleus accumbens during reward anticipation and in ventromedial prefrontal cortex during reward outcomes, indicating differential responses contingent on reward type in these regions. Results suggest that ASDs are characterized by reward-circuitry hypoactivation in response to monetary incentives but not in response to autism-relevant object images. The clinical implications of the double dissociation of reward type and temporal phase in reward circuitry function in ASD are discussed.

Performance of children with autism spectrum disorders on the dimension-change card sort task

Restricted and repetitive behaviors in autism spectrum disorders have been conceptualized to reflect impaired executive functions. In the present study, we investigated the performance of 6-17-year-old children with and without an autism spectrum disorder on a dimension-change card sort task that explicitly indicated sorting rules on every trial. Diagnostic groups did not differ in speed of responses after the first rule switch or in speed or accuracy on blocks with mixed versus single sort rules. However, performance of the ASD group was significantly slower and less accurate overall than the typically-developing group. Furthermore, within the ASD group, poorer DCCS task performance did not predict more severe autism symptoms. Implications for the executive dysfunction theory of autism are discussed.

Understanding emotional expression using prosodic analysis of natural speech: refining the methodology

Emotional expression is an essential function for daily life that can be severely affected in some psychological disorders. Laboratory-based procedures designed to measure prosodic expression from natural speech have shown early promise for measuring individual differences in emotional expression but have yet to produce robust within-group prosodic changes across various evocative conditions. This report presents data from three separate studies (total N = 464) that digitally recorded subjects as they verbalized their reactions to various stimuli. Format and stimuli were modified to maximize prosodic expression. Our results suggest that use of evocative slides organized according to either a dimensional (e.g., high and low arousal - pleasant, unpleasant and neutral valence) or categorical (e.g., fear, surprise, happiness) models produced robust changes in subjective state but only negligible change in prosodic expression. Alternatively, speech from the recall of autobiographical memories resulted in meaningful changes in both subjective state and prosodic expression. Implications for the study of psychological disorders are discussed.

Neural systems approaches to the neurogenetics of autism spectrum disorders

Autism is generally accepted as the most genetic of all the developmental neuropsychiatric syndromes. However, despite more than several decades of genetic study, the etiology of autism remains unknown, largely due to the genetic and phenotypic diversity, or heterogeneity, of this disorder, and the lack of biologically based classification systems. At the same time, in the neuroimaging literature, the body of research identifying candidate neural systems underlying aspects of autistic impairment has grown considerably, fueled by the advent of technologies such as functional magnetic resonance imaging (fMRI). Yet the findings from these neuroimaging studies have not been incorporated to inform the collection of samples for genetic studies of autism, which are predominantly based on a diagnosis of the disorder. This article presents a review of the genetics of autism and describes the genetic approaches that have been applied, including the phenotypic strategies that have been used to address heterogeneity and optimize the power of these genetic studies. With the increasing recognition that there may be different "autisms" (Geschwind and Levitt, 2007) with unique neural mechanisms, it is argued that neural systems research, using technologies such as fMRI, currently allows for the identification of more biologically informative phenotypes for genetic studies of autism and is positioned to identify informative neuroimaging markers for "neurogenetic" studies of the disorder. To illustrate this, we describe several candidate neural systems for the social communication impairment seen in autism, and the characteristic behavioral and physiological manifestations associated with these that could be incorporated into phenotypic assessments.

Illusory memories of emotionally charged words in autism spectrum disorder: further evidence for atypical emotion processing outside the social domain

Recent evidence suggests that individuals with ASD may not accumulate distinct representations of emotional information throughout development. On the basis of this observation we predicted that such individuals would not be any less likely to falsely remember emotionally significant as compared to neutral words when such illusory memories are induced by asking participants to study lists of words that are orthographically associated to these words. Our findings showed that typical participants are far less likely to experience illusory memories of emotionally charged as compared to neutral words. Individuals with ASD, on the other hand, did not exhibit this emotional modulation of false memories. We discuss this finding in relation to the role of emotional processing atypicalities in ASD.

Free recall and forgetting of emotionally arousing words in autism spectrum disorder

Since the earliest descriptions of individuals with autism spectrum disorders (ASDs) abnormalities in affective behaviours have been considered a prominent feature in their clinical manifestations. What remains unclear, however, is whether these altered emotional behaviours are a mere facet of abnormalities in socio-cognitive processes or whether they constitute a primary feature of the condition. A number of studies now indicate that emotional processing atypicalities in ASD extend to domains outside the broader context of social cognition leading us to suggest that the disorder may be characterised by basic abnormalities in how psychophysiological and cognitive emotional responses modulate one another [Gaigg, S. B. & Bowler, D. M. (2007). Differential fear conditioning in Asperger's syndrome: Implications for an amygdala theory of autism. Neuropsychologia, 45, 2125-2134]. In the current study, we show that although individuals with ASD, like typical individuals, exhibit a free recall advantage for emotionally arousing and semantically related neutral as compared to unrelated neutral words, they do not show reduced forgetting rates for arousing stimuli as do typical individuals. These observations provide further support for the view that psychophysiological emotional responses do not modulate cognitive processes normally in ASD and further implicate abnormalities of amygdala connectivity (in particular with the hippocampus) in the neuropathology underlying this disorder.