BackgroundIrritability in people with autism spectrum disorders (ASD) is common and impairing, yet its mechanisms remain understudied. We investigated symptom reporting and mechanisms of irritability in ASD, focusing on the relation between irritability and physiological stress responses.MethodsForty‐seven unmedicated boys with high‐functioning ASD (hfASD) and 23 typically developing boys aged 10–16 years completed a psychosocial stress test. Changes in cortisol, heart rate and heart rate variability throughout the test were recorded. Self‐ and parent‐reported measures of irritability were obtained. Irritability symptom reporting in the hfASD group was compared to two groups of boys without ASD: highly irritable boys (severe mood dysregulation, SMD; n = 40) and healthy‐control boys (HC; n = 30).ResultsBoys with hfASD scored significantly higher on irritability than HC boys, and they reported a pattern of irritability symptoms closely resembling that of boys with SMD. The internal consistency of irritability in hfASD was high by parent‐ and self‐report. Although boys with hfASD showed significant stress‐induced changes in cortisol and heart rate, those who rated themselves as highly irritable had lower cortisol levels throughout the test compared to those low on irritability. Participants rated as highly irritable by their parents showed blunted cortisol and heart rate responses to stress. The effects of irritability on heart rate, but not cortisol, were accounted for by trait anxiety.ConclusionsIrritability can be measured reliably in hfASD and is associated with distinct biological responses to stress.

The publication of the DSM-5 is nearing, yet a debate continues about the boundaries of bipolar disorder (BP) in children and adolescents. This article focuses on two key components of this debate that are often treated under the collective term mood dysregulation: the first is chronic irritability (and the proposed DSM-5 category of disruptive mood dysregulation disorder) and the other concerns short episodes of mania-like symptoms. We update our previous review [Stringaris in Eur Child Adolesc Psychiatry 20(2):61–66, 2011] and also present relevant neurobiological evidence. Most findings so far suggests that chronic, severe irritability is not a developmental presentation of mania. The diagnostic status of brief duration hypomania is less clear, with some evidence in support of its clinical relevance to BP. We end with recommendations for future research to inform classification and treatment.

Up to 40% of youth with autism spectrum disorder (ASD) also suffer from anxiety, and this comorbidity is linked with significant functional impairment. However, the mechanisms of this overlap are poorly understood. We investigated the interplay between ASD traits and anxiety during reward processing, known to be affected in ASD, in a community sample of 1472 adolescents (mean age=14.4 years) who performed a modified monetary incentive delay task as part of the Imagen project. Blood-oxygen-level dependent (BOLD) responses to reward anticipation and feedback were compared using a 2x2 analysis of variance test (ASD traits: low/high; anxiety symptoms: low/high), controlling for plausible covariates. In addition, we used a longitudinal design to assess whether neural responses during reward processing predicted anxiety at 2-year follow-up. High ASD traits were associated with reduced BOLD responses in dorsal prefrontal regions during reward anticipation and negative feedback. Participants with high anxiety symptoms showed increased lateral prefrontal responses during anticipation, but decreased responses following feedback. Interaction effects revealed that youth with combined ASD traits and anxiety, relative to other youth, showed high right insula activation when anticipating reward, and low right-sided caudate, putamen, medial and lateral prefrontal activations during negative feedback (all clusters PFWE<0.05). BOLD activation patterns in the right dorsal cingulate and right medial frontal gyrus predicted new-onset anxiety in participants with high but not low ASD traits. Our results reveal both quantitatively enhanced and qualitatively distinct neural correlates underlying the comorbidity between ASD traits and anxiety. Specific neural responses during reward processing may represent a risk factor for developing anxiety in ASD youth.

Background and objectivesThis study examined the effects of verbal information and approach-avoidance training on fear-related cognitive and behavioural responses about novel animals.MethodsOne hundred and sixty children (7–11 years) were randomly allocated to receive: a) positive verbal information about one novel animal and threat information about a second novel animal (verbal information condition); b) approach-avoidance training in which they repeatedly pushed away (avoid) or pulled closer (approach) pictures of the animals (approach-avoidance training), c) a combined condition in which verbal information was given prior to approach-avoidance training (verbal information + approach-avoidance training) and d) a combined condition in which approach-avoidance training was given prior to verbal information (approach-avoidance training + verbal information).ResultsThreat and positive information significantly increased and decreased fear beliefs and avoidance behaviour respectively. Approach-avoidance training was successful in training the desired behavioural responses but had limited effects on fear-related responses. Verbal information and both combined conditions resulted in significantly larger effects than approach-avoidance training. We found no evidence for an additive effect of these pathways.LimitationsThis study used a non-clinical sample and focused on novel animals rather than animals about which children already had experience or established fears. The study also compared positive information/approach with threat information/avoid training, limiting specific conclusions regarding the independent effects of these conditions.ConclusionsThe present study finds little evidence in support of a possible causal role for behavioural response training in the aetiology of childhood fear. However, the provision of verbal information appears to be an important pathway involved in the aetiology of childhood fear.

Difficulties with interpersonal relationships have been reported in children and adolescents with manic symptoms, even if they do not fulfil criteria for a manic episode. The role of social aptitude (SA) in youths with manic symptoms has never been examined in the general population. Moreover, no study has examined whether SA is differentially associated with dimensions of manic symptoms. We hypothesised that youth with predominantly undercontrol manic symptoms (characterised by irritability) would show lower levels of SA; conversely, youth with predominantly exuberant symptoms would show better than average social skills. Our sample comprised 5325 participants from the 2004 British Child and Adolescent Mental Health Survey (B-CAMHS04), mean age 10.3 years, SD = 3.3, 48 % girls. Manic symptoms were assessed with the Development and Wellbeing Assessment by interviewing parents and young people. Children and adolescents with manic symptoms had a lower SA score, compared to the general population by parent report, but not by self-report. SA score was higher in youths with predominantly exuberant manic symptoms compared to the general population; whereas the youths with predominantly undercontrol manic symptoms had lower SA scores by parent and self-report. Our results provide further evidence for the distinction between exuberant and undercontrol manic symptoms and highlight the need to focus on SA in future research.Electronic supplementary materialThe online version of this article (doi:10.1007/s00787-015-0800-7) contains supplementary material, which is available to authorized users.

IntroductionLittle is known about the neural correlates of mood states and the specific physiological changes associated with their valence and duration, especially in young people. Arterial spin labeling (ASL) imaging is particularly well-suited to study sustained cerebral states in young people, due to its robustness to low-frequency drift, excellent interscan reliability, and noninvasiveness. Yet, it has so far been underutilized for understanding the neural mechanisms underlying mood states in youth.MethodsIn this exploratory study, 21 healthy adolescents aged 16 to 18 took part in a mood induction experiment. Neutral, sad, and happy mood states were induced using film clips and explicit instructions. An ASL scan was obtained following presentation of each film clip.ResultsMood induction led to robust changes in self-reported mood ratings. Compared to neutral, sad mood was associated with increased regional cerebral blood flow (rCBF) in the left middle frontal gyrus and anterior prefrontal cortex, and decreased rCBF in the right middle frontal gyrus and the inferior parietal lobule. A decrease in self-reported mood from neutral to sad condition was associated with increased rCBF in the precuneus. Happy mood was associated with increased rCBF in medial frontal and cingulate gyri, the subgenual anterior cingulate cortex, and ventral striatum, and decreased rCBF in the inferior parietal lobule. The level of current self-reported depressive symptoms was negatively associated with rCBF change in the cerebellum and lingual gyrus following both sad and happy mood inductions.ConclusionsArterial spin labeling is sensitive to experimentally induced mood changes in healthy young people. The effects of happy mood on rCBF patterns were generally stronger than the effects of sad mood.