The familial basis of facial emotion recognition deficits in adolescents with conduct disorder and their unaffected relatives

BACKGROUND

There is accumulating evidence of impairments in facial emotion recognition in adolescents with conduct disorder (CD). However, the majority of studies in this area have only been able to demonstrate an association, rather than a causal link, between emotion recognition deficits and CD. To move closer towards understanding the causal pathways linking emotion recognition problems with CD, we studied emotion recognition in the unaffected first-degree relatives of CD probands, as well as those with a diagnosis of CD.

METHOD

Using a family-based design, we investigated facial emotion recognition in probands with CD (n = 43), their unaffected relatives (n = 21), and healthy controls (n = 38). We used the Emotion Hexagon task, an alternative forced-choice task using morphed facial expressions depicting the six primary emotions, to assess facial emotion recognition accuracy.

RESULTS

Relative to controls, the CD group showed impaired recognition of anger, fear, happiness, sadness and surprise (all p < 0.005). Similar to probands with CD, unaffected relatives showed deficits in anger and happiness recognition relative to controls (all p < 0.008), with a trend toward a deficit in fear recognition. There were no significant differences in performance between the CD probands and the unaffected relatives following correction for multiple comparisons.

CONCLUSIONS

These results suggest that facial emotion recognition deficits are present in adolescents who are at increased familial risk for developing antisocial behaviour, as well as those who have already developed CD. Consequently, impaired emotion recognition appears to be a viable familial risk marker or candidate endophenotype for CD.

Atypical neural responses to vocal anger in attention-deficit/hyperactivity disorder

BACKGROUND

Deficits in facial emotion processing, reported in attention-deficit/hyperactivity disorder (ADHD), have been linked to both early perceptual and later attentional components of event-related potentials (ERPs). However, the neural underpinnings of vocal emotion processing deficits in ADHD have yet to be characterised. Here, we report the first ERP study of vocal affective prosody processing in ADHD.

METHODS

Event-related potentials of 6-11-year-old children with ADHD (n = 25) and typically developing controls (n = 25) were recorded as they completed a task measuring recognition of vocal prosodic stimuli (angry, happy and neutral). Audiometric assessments were conducted to screen for hearing impairments.

RESULTS

Children with ADHD were less accurate than controls at recognising vocal anger. Relative to controls, they displayed enhanced N100 and attenuated P300 components to vocal anger. The P300 effect was reduced, but remained significant, after controlling for N100 effects by rebaselining. Only the N100 effect was significant when children with ADHD and comorbid conduct disorder (n = 10) were excluded.

CONCLUSION

This study provides the first evidence linking ADHD to atypical neural activity during the early perceptual stages of vocal anger processing. These effects may reflect preattentive hyper-vigilance to vocal anger in ADHD.

Cognitive training for attention-deficit/hyperactivity disorder: meta-analysis of clinical and neuropsychological outcomes from randomized controlled trials

OBJECTIVE

The authors performed meta-analyses of randomized controlled trials to examine the effects of cognitive training on attention-deficit/hyperactivity disorder (ADHD) symptoms, neuropsychological deficits, and academic skills in children/adolescents with ADHD.

METHOD

The authors searched Pubmed, Ovid, Web of Science, ERIC, and CINAHAL databases through May 18, 2014. Data were aggregated using random-effects models. Studies were evaluated with the Cochrane risk of bias tool.

RESULTS

Sixteen of 695 nonduplicate records were analyzed (759 children with ADHD). When all types of training were considered together, there were significant effects on total ADHD (standardized mean difference [SMD] = 0.37, 95% CI = 0.09-0.66) and inattentive symptoms (SMD = 0.47, 95% CI = 0.14-0.80) for reports by raters most proximal to the treatment setting (i.e., typically unblinded). These figures decreased substantially when the outcomes were provided by probably blinded raters (ADHD total: SMD = 0.20, 95% CI = 0.01-0.40; inattention: SMD = 0.32, 95% CI = -0.01 to 0.66). Effects on hyperactivity/impulsivity symptoms were not significant. There were significant effects on laboratory tests of working memory (verbal: SMD = 0.52, 95% CI = 0.24-0.80; visual: SMD = 0.47, 95% CI = 0.23-0.70) and parent ratings of executive function (SMD = 0.35, 95% CI = 0.08-0.61). Effects on academic performance were not statistically significant. There were no effects of working memory training, specifically on ADHD symptoms. Interventions targeting multiple neuropsychological deficits had large effects on ADHD symptoms rated by most proximal assessors (SMD = 0.79, 95% CI = 0.46-1.12).

CONCLUSION

Despite improving working memory performance, cognitive training had limited effects on ADHD symptoms according to assessments based on blinded measures. Approaches targeting multiple neuropsychological processes may optimize the transfer of effects from cognitive deficits to clinical symptoms.

Spontaneous activity in the waiting brain: a marker of impulsive choice in attention-deficit/hyperactivity disorder?

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In controls very low frequency (VLF) EEG attenuated during task and waiting periods.

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In ADHD there was less attenuation during tasks and none at all during waiting.

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Degree of waiting attenuation correlated with parent's ratings of impulsive choice.

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Aberrant waiting VLF EEG may be a neural marker for impulsive choice in ADHD.

Background

Spontaneous very low frequency oscillations (VLFO), seen in the resting brain, are attenuated when individuals are working on attention demanding tasks or waiting for rewards (Hsu et al., 2013). Individuals with attention-deficit/hyperactivity disorder (ADHD) display excess VLFO when working on attention tasks. They also have difficulty waiting for rewards. Here we examined the waiting brain signature in ADHD and its association with impulsive choice.

Methods

DC-EEG from 21 children with ADHD and 21 controls (9–15 years) were collected under four conditions: (i) resting; (ii) choosing to wait; (iii) being “forced” to wait; and (iv) working on a reaction time task. A questionnaire measured two components of impulsive choice.

Results

Significant VLFO reductions were observed in controls within anterior brain regions in both working and waiting conditions. Individuals with ADHD showed VLFO attenuation while working but to a reduced level and none at all when waiting. A closer inspection revealed an increase of VLFO activity in temporal regions during waiting. Excess VLFO activity during waiting was associated with parents’ ratings of temporal discounting and delay aversion.

Conclusions

The results highlight the potential role for waiting-related spontaneous neural activity in the pathophysiology of impulsive decision-making of ADHD.

The development of emotion recognition from facial expressions and non-linguistic vocalizations during childhood

Sensitivity to facial and vocal emotion is fundamental to children's social competence. Previous research has focused on children's facial emotion recognition, and few studies have investigated non-linguistic vocal emotion processing in childhood. We compared facial and vocal emotion recognition and processing biases in 4- to 11-year-olds and adults. Eighty-eight 4- to 11-year-olds and 21 adults participated. Participants viewed/listened to faces and voices (angry, happy, and sad) at three intensity levels (50%, 75%, and 100%). Non-linguistic tones were used. For each modality, participants completed an emotion identification task. Accuracy and bias for each emotion and modality were compared across 4- to 5-, 6- to 9- and 10- to 11-year-olds and adults. The results showed that children's emotion recognition improved with age; preschoolers were less accurate than other groups. Facial emotion recognition reached adult levels by 11 years, whereas vocal emotion recognition continued to develop in late childhood. Response bias decreased with age. For both modalities, sadness recognition was delayed across development relative to anger and happiness. The results demonstrate that developmental trajectories of emotion processing differ as a function of emotion type and stimulus modality. In addition, vocal emotion processing showed a more protracted developmental trajectory, compared to facial emotion processing. The results have important implications for programmes aiming to improve children's socio-emotional competence.

Far from idle: Four ways in which growing knowledge of the 'resting' brain is transforming our understanding of the causes of childhood disorder

Historians of science continue to debate the importance of individual inspiration and personal creativity as fuel in the engine of scientific progress. While true that, in general, scientific knowledge advances cautiously by careful experimentation, painstaking observation and the gradual accumulation of evidence occasionally a field of enquiry can be revolutionised by a single, perhaps simple, yet inspired and profound insight. Such breakthroughs are most likely to occur when an individual moves outside the intellectual tramlines that normally constrain scientific thinking, leaving them able to look at old evidence in new and original ways. The reception of such original insights by the research community varies considerably, of course. Some insights may be 'too original'--a step too far in what is normally an incremental journey of discovery. Some ideas, enthusiastically accepted initially, may burn out before making any real impression. Other ideas revolutionize a field--producing a cascade of hypotheses and lines of enquiry that lead to new discoveries which permanently change the scientific landscape. The issue of scientific creativity was very much in my mind when reading through the papers slated to appear in the current journal number. One article in particular, by Pannekoeke and colleagues on intrinsic brain organisation in depressed adolescents, initiated a chain of thought that led me to my focus for this editorial. A development that provides perhaps the most compelling recent example of the transformative power of individual inspiration in the field of cognitive neuroscience--a development which is also beginning to have profound implications for models of childhood mental disorders.

The foundations of next generation attention-deficit/hyperactivity disorder neuropsychology: building on progress during the last 30 years

In this short overview we have illustrated 30 years of progress in the field of ADHD neuropsychology through a selective presentation of studies published in the JCPP. Clearly this is not an exhaustive list of papers (we had to leave many excellent studies out) and obviously many studies published in other journals have had an equally significant impact on the field. Nevertheless, it is clear that the JCPP has contributed in important ways to providing the empirical and intellectual foundations of the next generation of ADHD neuropsychological models in terms of insight regarding context dependence, complexity and heterogeneity, and diagnostic specificity and sensitivity. Furthermore, articles have highlighted the importance of a developmental perspective on neuropsychological deficits in ADHD as well as the possibility that they could be targeted with new and novel treatments. Our hope is that we will continue to witness similar growth in understanding over the next 30 years, and that the JCPP will continue to be at the forefront of this progress.

Different effects of adding white noise on cognitive performance of sub-, normal and super-attentive school children

OBJECTIVES

Noise often has detrimental effects on performance. However, because of the phenomenon of stochastic resonance (SR), auditory white noise (WN) can alter the "signal to noise" ratio and improve performance. The Moderate Brain Arousal (MBA) model postulates different levels of internal "neural noise" in individuals with different attentional capacities. This in turn determines the particular WN level most beneficial in each individual case-with one level of WN facilitating poor attenders but hindering super-attentive children. The objective of the present study is to find out if added WN affects cognitive performance differently in children that differ in attention ability.

METHODS

Participants were teacher-rated super- (N = 25); normal- (N = 29) and sub-attentive (N = 36) children (aged 8 to 10 years). Two non-executive function (EF) tasks (a verbal episodic recall task and a delayed verbal recognition task) and two EF tasks (a visuo-spatial working memory test and a Go-NoGo task) were performed under three WN levels. The non-WN condition was only used to control for potential differences in background noise in the group testing situations.

RESULTS

There were different effects of WN on performance in the three groups-adding moderate WN worsened the performance of super-attentive children for both task types and improved EF performance in sub-attentive children. The normal-attentive children's performance was unaffected by WN exposure. The shift from moderate to high levels of WN had little further effect on performance in any group.

SIGNIFICANCE

The predicted differential effect of WN on performance was confirmed. However, the failure to find evidence for an inverted U function challenges current theories. Alternative explanations are discussed. We propose that WN therapy should be further investigated as a possible non-pharmacological treatment for inattention.

Editorial perspective: Laying the foundations for next generation models of ADHD neuropsychology

The JCPP has just published a virtual issue focusing specifically on the journal's contribution to progress in the field of ADHD neuropsychology over last 30 years and its role in establishing the foundations of next generation ADHD neuropsychology models. The virtual issue is structured around six themes. Here we provide a précis of the issue summarizing these themes and illustrating each with a reference to an influential paper published over the last 5 years.

Editorial: Translational genetics of child psychopathology: a distant dream?

For decades now twin, family and adoption studies have pointed to a substantial role for genetic factors in risk for psychiatric disorder. Behaviour genetic studies are not, of course, designed to tell us about the 'genetic architecture' of disorders - the number of risk variants involved, their frequency, or their effects sizes - but their findings clearly suggest that given the high levels of heritability detected, identifying the gene variants involved could provide important pointers to aetiology, and might well have implications for treatment. In and of themselves heritability findings have little practical value as a basis for a translational genetics of psychiatric disorders. They cannot help us identify pathophysiological pathways that need to be targeted through therapeutic innovation or inform the sort of tailoring of treatments to individual biological 'types' to promote personalized medicine. To do these things we need to move from estimating heritability to identifying specific genetic markers implicating specific neuro-biological systems.

'What's up, (R)DoC?'--can identifying core dimensions of early functioning help us understand, and then reduce, developmental risk for mental disorders?

In the U.S. the National Institute of Mental Health (NIMH), the main funder of mental health research in the world, has recently changed its funding model to promote a radically new perspective for mental health science. This bold, and for some controversial, initiative, termed the Research Diagnostic Criteria (or RDoC for short), intends to shift the focus of research, and eventually clinical practice, away from existing diagnostic categories, as recently updated in the DSM-5, towards 'new ways of classifying psychopathology based on dimensions of observable behavior and neurobiological measures.' This reorientation from discrete categorical disorder manifestations to underlying cross-cutting dimensions of individual functioning has generated considerable debate across the community of mental health researchers and clinicians (with strong views voiced both pro and con). Given its pivotal role in defining the research agenda globally, there is little doubt that this US science funding initiative will also have ramifications for researchers and clinicians worldwide. In this Editorial we focus specifically on the translational potential of the dimensional RDoC approach, properly extended to developmental models of early risk, in terms of its value as a potential driver of early intervention/prevention models; in the current issue of the JCPP this is exemplified by a number of papers thata address the mapping of underlying dimensions of core functioning to disorder risk, providing evidence for their potential predictive power as early markers of later disorder processes.

Behavioral interventions in attention-deficit/hyperactivity disorder: a meta-analysis of randomized controlled trials across multiple outcome domains

OBJECTIVE

Behavioral interventions are recommended as attention-deficit/hyperactivity disorder (ADHD) treatments. However, a recent meta-analysis found no effects on core ADHD symptoms when raters were probably blind to treatment allocation. The present analysis is extended to a broader range of child and parent outcomes.

METHOD

A systematic search in PubMed, Ovid, Web of Knowledge, ERIC, and CINAHAL databases (up to February 5, 2013) identified published randomized controlled trials measuring a range of patient and parent outcomes for children and adolescents diagnosed with ADHD (or who met validated cutoffs on rating scales).

RESULTS

Thirty-two of 2,057 nonduplicate screened records were analyzed. For assessments made by individuals closest to the treatment setting (usually unblinded), there were significant improvements in parenting quality (standardized mean difference [SMD] for positive parenting 0.68; SMD for negative parenting 0.57), parenting self-concept (SMD 0.37), and child ADHD (SMD 0.35), conduct problems (SMD 0.26), social skills (SMD 0.47), and academic performance (SMD 0.28). With probably blinded assessments, significant effects persisted for parenting (SMD for positive parenting 0.63; SMD for negative parenting 0.43) and conduct problems (SMD 0.31).

CONCLUSION

In contrast to the lack of blinded evidence of ADHD symptom decrease, behavioral interventions have positive effects on a range of other outcomes when used with patients with ADHD. There is blinded evidence that they improve parenting and decrease childhood conduct problems. These effects also may feed through into a more positive parenting self-concept but not improved parent mental well-being.

Reward: commentary. Temporal discounting in conduct disorder: toward an experience-adaptation hypothesis of the role of psychosocial insecurity

Young people with conduct disorder often experience histories of psychosocial adversity and socioeconomic insecurity. For these individuals, real-world future outcomes are not only delayed in their delivery but also highly uncertain. Under such circumstances, accentuated time preference (extreme favoring of the present over the future) is a rational response to the everyday reality of social and economic transactions. Building on this observation, the author sets out the hypothesis that the exaggerated temporal discounting displayed by individuals with conduct disorder reported by White et al. (2014) is an adaptation to chronic exposure to psychosocial insecurity during development. The author postulates that this adaptation leads to (a) a decision-making bias whereby delay and uncertainty are coded as inseparable characteristics of choice outcomes and/or (b) reprogramming of the brain networks regulating intertemporal decision making. Future research could explore the putative role of environmental exposures to adversity in the development of exaggerated temporal discounting in conduct disorder as well as the mediating role of putative cognitive and neurobiological adaptations.

Emotion-recognition abilities and behavior problem dimensions in preschoolers: evidence for a specific role for childhood hyperactivity

Facial emotion-recognition difficulties have been reported in school-aged children with behavior problems; little is known, however, about either this association in preschool children or with regard to vocal emotion recognition. The current study explored the association between facial and vocal emotion recognition and behavior problems in a sample of 3 to 6-year-old children. A sample of 57 children enriched for risk of behavior problems (41 were recruited from the general population while 16 had been referred for behavior problems to local clinics) were each presented with a series of vocal and facial stimuli expressing different emotions (i.e., angry, happy, and sad) of low and high intensity. Parents rated children's externalizing and internalizing behavior problems. Vocal and facial emotion recognition accuracy was negatively correlated with externalizing but not internalizing behavior problems independent of emotion type. The effects with the externalizing domain were independently associated with hyperactivity rather than conduct problems. The results highlight the importance of using vocal as well as facial stimuli when studying the relationship between emotion-recognition and behavior problems. Future studies should test the hypothesis that difficulties in responding to adult instructions and commands seen in children with attention deficit/hyperactivity disorder (ADHD) may be due to deficits in the processing of vocal emotions.

Genetic relationship between five psychiatric disorders estimated from genome-wide SNPs

Most psychiatric disorders are moderately to highly heritable. The degree to which genetic variation is unique to individual disorders or shared across disorders is unclear. To examine shared genetic etiology, we use genome-wide genotype data from the Psychiatric Genomics Consortium (PGC) for cases and controls in schizophrenia, bipolar disorder, major depressive disorder, autism spectrum disorders (ASD) and attention-deficit/hyperactivity disorder (ADHD). We apply univariate and bivariate methods for the estimation of genetic variation within and covariation between disorders. SNPs explained 17-29% of the variance in liability. The genetic correlation calculated using common SNPs was high between schizophrenia and bipolar disorder (0.68 ± 0.04 s.e.), moderate between schizophrenia and major depressive disorder (0.43 ± 0.06 s.e.), bipolar disorder and major depressive disorder (0.47 ± 0.06 s.e.), and ADHD and major depressive disorder (0.32 ± 0.07 s.e.), low between schizophrenia and ASD (0.16 ± 0.06 s.e.) and non-significant for other pairs of disorders as well as between psychiatric disorders and the negative control of Crohn's disease. This empirical evidence of shared genetic etiology for psychiatric disorders can inform nosology and encourages the investigation of common pathophysiologies for related disorders.

Nonpharmacological interventions for ADHD: systematic review and meta-analyses of randomized controlled trials of dietary and psychological treatments

OBJECTIVE

Nonpharmacological treatments are available for attention deficit hyperactivity disorder (ADHD), although their efficacy remains uncertain. The authors undertook meta-analyses of the efficacy of dietary (restricted elimination diets, artificial food color exclusions, and free fatty acid supplementation) and psychological (cognitive training, neurofeedback, and behavioral interventions) ADHD treatments.

METHOD

Using a common systematic search and a rigorous coding and data extraction strategy across domains, the authors searched electronic databases to identify published randomized controlled trials that involved individuals who were diagnosed with ADHD (or who met a validated cutoff on a recognized rating scale) and that included an ADHD outcome.

RESULTS

Fifty-four of the 2,904 nonduplicate screened records were included in the analyses. Two different analyses were performed. When the outcome measure was based on ADHD assessments by raters closest to the therapeutic setting, all dietary (standardized mean differences=0.21-0.48) and psychological (standardized mean differences=0.40-0.64) treatments produced statistically significant effects. However, when the best probably blinded assessment was employed, effects remained significant for free fatty acid supplementation (standardized mean difference=0.16) and artificial food color exclusion (standardized mean difference=0.42) but were substantially attenuated to nonsignificant levels for other treatments.

CONCLUSIONS

Free fatty acid supplementation produced small but significant reductions in ADHD symptoms even with probably blinded assessments, although the clinical significance of these effects remains to be determined. Artificial food color exclusion produced larger effects but often in individuals selected for food sensitivities. Better evidence for efficacy from blinded assessments is required for behavioral interventions, neurofeedback, cognitive training, and restricted elimination diets before they can be supported as treatments for core ADHD symptoms.

Neuronal oscillations in the EEG under varying cognitive load: a comparative study between slow waves and faster oscillations

OBJECTIVE

This study has been specifically designed to investigate very low frequency neuronal oscillations (VLFO, <0.5 Hz) during resting states and during goal-directed tasks of graded difficulty levels, quantify the changes that the slow waves undergo in these conditions and compare them with those for higher frequency bands (namely delta, theta and alpha).

METHODS

To this end we developed a multistage signal processing methodology comprising blind source separation coupled with a neural network based feature extraction and classification method.

RESULTS

Changes in the amplitude and phase of brain sources estimates in the VLF band between rest and task were enhanced with increased task difficulty, but remained lower than those experienced in higher frequency bands. The slow wave variations were also significantly correlated with task performance measures, and hence with the level of task-directed attention.

CONCLUSIONS

These findings suggest that besides their prominent sensitivity to external stimulation, VLFOs also contribute to the cortical ongoing background activity which may not be specifically related to task-specific attention and performance.

SIGNIFICANCE

Our work provides important insight into the association between VLF brain activity and conventional EEG frequency bands, and presents a novel framework for assessing neural activity during various mental conditions and psychiatric states.

Neuroeconomics of attention-deficit/hyperactivity disorder: differential influences of medial, dorsal, and ventral prefrontal brain networks on suboptimal decision making?

Psychiatric neuroeconomics offers an alternative approach to understanding mental disorders by studying the way disorder-related neurobiological alterations constrain economic agency, as revealed through decisions about choices between future goods. In this article, we apply this perspective to understand suboptimal decision making in attention-deficit/hyperactivity disorder (ADHD) by integrating recent advances in the neuroscience of decision making and studies of the pathophysiology of ADHD. We identify three brain networks as candidates for further study and develop specific hypotheses about how these could be implicated in ADHD. First, we postulate that altered patterns of connectivity within a network linking medial prefrontal cortex and posterior cingulate cortex (i.e., the default mode network) disrupts ordering of utilities, prospection about desired future states, setting of future goals, and implementation of aims. Second, we hypothesize that deficits in dorsal frontostriatal networks, including the dorsolateral prefrontal cortex and dorsal striatum, produce executive dysfunction-mediated impairments in the ability to compare outcome options and make choices. Third, we propose that dopaminergic dysregulation in a ventral frontostriatal network encompassing the orbitofrontal cortex, ventral striatum, and amygdala disrupts processing of cues of future utility, evaluation of experienced outcomes (feedback), and learning of associations between cues and outcomes. Finally, we extend this perspective to consider three contemporary themes in ADHD research.

Children born small for gestational age are not at special risk for preschool emotion and behaviour problems

Despite the wealth of literature examining long term outcomes of preterm low birthweight children, few studies have directly assessed the developmental impact of being born full term but small for gestational age (SGA). We aim to determine whether (i) being SGA increases preschool behavioural problems and (ii) other risk factors operate differently in SGA and appropriate for gestational age (AGA) controls. 550 New Zealand European mothers and their 3.5 year old children participated in this study. All children were born at full term (>37 weeks' gestation) and approximately half were SGA (≤sex specific 10th percentile for gestation) the remainder were AGA controls. Extensive data were collected at the child's birth, 1 year and 3.5 years. Behavioural problems were measured when children were 3.5 years, using the Strengths and Difficulties Questionnaire (SDQ). Multiple regression analyses were used to examine the associations between risk factors and behavioural problems; statistical weighting was used for analyses of the total study group. There was no significant difference in behavioural problems between SGA and AGA groups. In the total sample the significant predictors of behavioural problems included: mothers' school leaving age; smoking during pregnancy; maternal alcohol use during pregnancy; and absence of the father. Predictors of behavioural problems were found to be the same for SGA and AGA groups. These results do not support the view that SGA is a risk for behavioural preschool difficulties or that SGA children are sensitised to risks known to be associated with such difficulties in the preschool years.