Reward processing in adolescents with social phobia and depression

OBJECTIVE

Impaired reward processing has been found in individuals with anxiety, but also major depressive disorder (MDD). Here, we studied neural correlates of reward anticipation and processing in a sample of youth with severe social phobia and comorbid depression (SP/MDD) and investigated the specific contribution of SP and MDD symptoms.

METHODS

15 affected, unmedicated and 25 typically developing (TD) youth completed a monetary gambling task, which included a positive, negative and ambiguous reward condition. Event-related potentials representing cue processing (cue P300), reward anticipation (stimulus preceding negativity, SPN), reward sensitivity (feedback related negativity, FRN) and reward processing (reward P300) were analysed.

RESULTS

Reduced amplitudes of the right hemispheric (r)SPN and reward P300 were observed in SP/MDD compared to TD. Within the SP/MDD group SP symptoms correlated with larger rSPN, and FRN amplitudes. MDD symptoms correlated with smaller rSPN and smaller FRN positive-negative difference wave.

CONCLUSIONS

Reward anticipation and feedback processing are reduced in SP/MDD. Higher SP symptoms are associated with stronger neural activation during reward anticipation and reward sensitivity. Depressive symptoms are associated with decreased reward anticipation and sensitivity. Findings are in line with the theory of heightened vigilance in anxiety and blunted reward processing due to anhedonia in MDD.

SIGNIFICANCE

The study results can inform behavioural interventions for SP and MDD.

The effect of perceptual expectation on processing gain, attention and the perceptual decision bias in children and adolescents with Autism Spectrum Disorder (ASD)

Perceptual expectations influence perception, attention and the perceptual decision bias during visuospatial orienting, which is impaired in individuals with Autism Spectrum Disorder (ASD). In this study, we investigated whether during visuospatial orienting, perceptual expectations in ASD differentially influence perception, attention and the perceptual decision bias relative to neurotypical controls (NT). Twenty-three children and adolescents with ASD and 23 NT completed a visuospatial orienting task, which compared the effect of a valid relative to an invalid perceptual expectation on target detection (cue validity effect). Group differences were calculated regarding the cue validity effect on neural correlates of processing gain (N1a amplitude) and attention (N1pc amplitude), the perceptual decision bias and mean reaction time (RT). In ASD relative to NT, findings showed a reduced processing gain for validly relative to invalidly cued targets and increased attentional response following invalidly relative to validly cued targets. Increased attention correlated with faster performance across groups. Increased processing correlated with a higher perceptual decision bias and faster mean RT in NT, but not in ASD. Results suggest that during visuospatial orienting, perceptual expectations in ASD may drive changes in sensory processing and stimulus-driven attention, which may differentially guide behavioural responses.

Intention Attribution in Children and Adolescents with Autism Spectrum Disorder: An EEG Study

The ability to infer intentions from observed behavior and predict actions based on this inference, known as intention attribution (IA), has been hypothesized to be impaired in individuals with autism spectrum disorder (ASD). The underlying neural processes, however, have not been conclusively determined. The aim of this study was to examine the neural signature of IA in children and adolescents with ASD, and to elucidate potential links to contextual updating processes using electroencephalography. Results did not indicate that IA or early contextual updating was impaired in ASD. However, there was evidence of aberrant processing of expectation violations in ASD, particularly if the expectation was based on IA. Results are discussed within the context of impaired predictive coding in ASD.

Brain stimulation by tDCS as treatment option in Autism Spectrum Disorder-A systematic literature review

Autism Spectrum Disorder (ASD) is a neurodevelopmental disorder characterized by deficits in social communication and interaction as well as stereotypical and repetitive behavior. Transcranial direct current stimulation (tDCS) has been proposed as a new intervention method in ASD with the potential to improve cognitive, motor and social communication abilities by targeting specific underlying neuronal alterations. Here, we report results of a systematic literature review on tDCS effects on EEG and behavioral outcomes, and discuss tDCS as treatment option for ASD. PsychInfo, PubMed, ScienceDirect, Web of Science, https://clinicaltrials.gov and the German Clinical Trials Register (Deutsches Register Klinischer Studien) were searched systematically for randomized, sham-controlled clinical trials of tDCS in individuals with ASD, and information regarding study designs and relevant results was extracted. Six eligible studies were identified. The dorsolateral prefrontal cortex (DLPFC) was targeted in four trials, with core ASD symptoms and working memory as outcome measures. One study targeted the primary motor cortex (M1) with motor skills as outcome, and one study targeted the temporoparietal junction (TPJ) with social communication skills as outcome measure. Comparison of the implemented study designs showed high methodological variability between studies regarding stimulation parameters, trial design and outcome measures. Study results indicate initial support for improved cognitive and social communication skills in ASD following tDCS stimulation. However, systematic and comparison studies on the best combination of stimulation intensity, duration, location as well as task related stimulation are necessary, before results can be translated into routine clinical application.

Phase-IIa randomized, double-blind, sham-controlled, parallel group trial on anodal transcranial direct current stimulation (tDCS) over the left and right tempo-parietal junction in autism spectrum disorder-StimAT: study protocol for a clinical trial

Background

Autism spectrum disorder (ASD) is characterized by impaired social communication and interaction, and stereotyped, repetitive behaviour and sensory interests. To date, there is no effective medication that can improve social communication and interaction in ASD, and effect sizes of behaviour-based psychotherapy remain in the low to medium range. Consequently, there is a clear need for new treatment options. ASD is associated with altered activation and connectivity patterns in brain areas which process social information. Transcranial direct current stimulation (tDCS) is a technique that applies a weak electrical current to the brain in order to modulate neural excitability and alter connectivity. Combined with specific cognitive tasks, it allows to facilitate and consolidate the respective training effects. Therefore, application of tDCS in brain areas relevant to social cognition in combination with a specific cognitive training is a promising treatment approach for ASD.

Methods

A phase-IIa pilot randomized, double-blind, sham-controlled, parallel-group clinical study is presented, which aims at investigating if 10 days of 20-min multi-channel tDCS stimulation of the bilateral tempo-parietal junction (TPJ) at 2.0 mA in combination with a computer-based cognitive training on perspective taking, intention and emotion understanding, can improve social cognitive abilities in children and adolescents with ASD. The main objectives are to describe the change in parent-rated social responsiveness from baseline (within 1 week before first stimulation) to post-intervention (within 7 days after last stimulation) and to monitor safety and tolerability of the intervention. Secondary objectives include the evaluation of change in parent-rated social responsiveness at follow-up (4 weeks after end of intervention), change in other ASD core symptoms and psychopathology, social cognitive abilities and neural functioning post-intervention and at follow-up in order to explore underlying neural and cognitive mechanisms.

Discussion

If shown, positive results regarding change in parent-rated social cognition and favourable safety and tolerability of the intervention will confirm tDCS as a promising treatment for ASD core-symptoms. This may be a first step in establishing a new and cost-efficient intervention for individuals with ASD.

Trial registration

The trial is registered with the German Clinical Trials Register (DRKS), DRKS00014732. Registered on 15 August 2018.

Protocol version

This study protocol refers to protocol version 1.2 from 24 May 2019.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13063-021-05172-1.

Facilitation of biological motion processing by group-based autism specific social skills training

Abnormalities in neurophysiological correlates of social perception are a well-known feature of autism spectrum disorder (ASD). However, little is known if and how ASD specific behavioral interventions may affect neural processing in ASD. The aim of the current study was to investigate for the first time, whether the group-based social skills training SOSTA-FRA would elicit changes in neurophysiological correlates of social perception in high-functioning ASD individuals aged 8-17 years. Event-related potentials (ERPs) of a facial emotion recognition (FER) and a biological motion perception task were examined. ERPs were compared between a randomized intervention and a treatment as usual group at three time points (baseline, post-intervention, and at 3 months follow-up). A reduction of P100 amplitude in the right hemisphere and a trend toward reduced N200 latency in the biological motion task were found after the training only in the intervention group, whereas behavioral performance remained stable. Change in N200 latencies and parent-rated social responsiveness showed small but statistically nonsignificant correlations. No changes were observed regarding FER. Results indicate that the intervention changed neural correlates of social perception in ASD. Especially neural correlates of biological motion perception, which is an important prerequisite for successful social interaction, were sensitive to change. ERPs of social perception tasks that are impaired in ASD can well be used to objectively measure neural processing improvement by behavioral intervention. Autism Res 2018, 11: 1376-1387. © 2018 International Society for Autism Research, Wiley Periodicals, Inc. LAY SUMMARY: It is well known that people with autism spectrum disorder (ASD) process social information differently than other people and that these differences can also be seen in their brain activity. We also know that behavioral therapies, such as group-based social skills trainings can help people with ASD improve their behavior. But it is unclear how therapy changes social processing in the brain. The aim of our study was therefore to examine how neural processing of social stimuli changed after behavioral intervention. Comparing a group of children and adolescents that received the group-based social skills training SOSTA-FRA to a control group we found that the neural processing of human motion became faster and involved less brain resources after the intervention, while behavioral performance remained stable. No changes were seen for the processing of emotional facial expressions. We recommend that future studies should also analyze changes in brain function as well as behavioral changes as a secondary therapy outcome parameter.

Elucidating the neurophysiological underpinnings of autism spectrum disorder: new developments

The study of neurophysiological approaches together with rare and common risk factors for Autism Spectrum Disorder (ASD) allows elucidating the specific underlying neurobiology of ASD. Whereas most neurophysiologically based research in ASD to date has focussed on case-control differences based on the DSM- or ICD-based categorical ASD diagnosis, more recent studies have aimed at studying genetically and/or neurophysiologically defined homogeneous ASD subgroups for specific neuronal biomarkers. This review addresses the neurophysiological investigation of ASD by evoked and event-related potentials, by EEG/MEG connectivity measures such as coherence, and transcranial magnetic stimulation. As an example of classical neurophysiological studies in ASD, we report event-related potential studies which have illustrated which brain areas and processing stages are affected in the visual perception of socially relevant stimuli. However, a paradigm shift has taken place in recent years focussing on how these findings can be tracked down to basic neuronal functions such as deficits in cortico-cortical connectivity and the interaction between brain areas. Disconnectivity, for example, can again be related to genetically induced shifts in the excitation/inhibition balance. Genetic causes of ASD may be grouped by their effects on the brain's system level to identify ASD subgroups which respond differentially to therapeutic interventions.