The present study is the first to investigate the differences in subjective and cortical responses in children with SAD, healthy controls (HC) and a clinical control group with mixed anxiety disorders (MAD) by means of cognitive appraisals (reactivity, reappraisal). Importantly, all children showed reduced subjective reactivity following reappraisal, supporting cognitive reappraisal as a very beneficial emotion regulation strategy already in children with anxiety disorders. Neurally, a reduced electrocortical reactivity following reappraisal was evident only in older children and in boys. In accordance with our hypothesis, this suggests that the LPP provides a measure of emotion regulation, especially in older pediatric populations. Furthermore, we predicted that, compared to HC children, children with SAD would show increased subjective and late ERP responses to socially threatening children’s faces. This hypothesis was partly confirmed, children with SAD showed (a) generally heightened subjective reactivity to angry children’s faces in both conditions (reactivity and reappraisal), but (b) no differences in ERPs when compared to HC children. Finally, contrary to our hypothesis, we did not find any differences between SAD, MAD or HC groups in reappraisal-related changes of subjective or LPP outcome measures.
Enhanced Subjective Reactivity in SAD Children, But No Clinical Effects on ERP Reactivity or Reappraisal Modulation
The results showed that children with SAD responded with heightened subjective reactivity in both conditions when compared to HC and MAD. An overall enhanced subjective reactivity in SAD children indicates that SAD children evaluate an angry looking peer as threatening and that this cannot be fully reduced by means of cognitive appraisal as applied in our brief experimental intervention. Still, cognitive reappraisal had a positive effect on subjective arousal across all participants, including both clinical groups, underpinning its value for addressing negative emotion in childhood anxiety disorders.
Interestingly, the enhanced subjective reactivity in SAD children was not reflected in their ERPs. Such discordance between subjective and neural responses has been seen before, in both children [
14] and adults [
61]. In addition to the absence of group differences in ERP reactivity, groups did not differ in subjective or electrocortical response modulation using reappraisal. As expected, compared to the reactivity condition, all children reported lower subjective arousal in the reappraisal condition. Yet, this did not translate uniformly to the neural indices since a reappraisal-related LPP reduction was only present in older children and in boys. Generally, the (dys-)coherence between different emotional subsystems (physiological, experiential, behavioral) can vary by interindividual differences, experimental setups, the type of assessed emotion, psychopathology and by developmental stages of participants [
61,
62]. In this line, previous research suggests that neural correlates of emotion (dys-)regulation in anxiety most likely develop at older ages during late childhood and adolescents, leading to discordance between subjective and neural measures in younger samples [
14,
25], presumably due to brain maturation and increased cognitive control in older children [
62]. Taken together, this lack of coherence between subjective and electrocortical measures emphasizes the importance of assessing emotional reactivity and regulation with multiple methods [
63] and in samples with a broad age range of children and adolescents to capture potential developmental changes in emotional coherence.
Our study partially replicates, and importantly extends, previous research findings using children’s faces as stimuli. Several studies similarly did not find differences between children with SAD and HC in both early [
16‐
18] and late [
16] ERP responses to emotional adult faces, while other studies have reported enhanced LPPs in response to threatening adult faces [
17,
18,
20]. A previous study found no group differences in habitual use of reappraisal in children with SAD when compared to HC [
64,
65], which confirms our clinical null findings. However, the absence of group differences in the effectiveness of reappraisal conflicts with existing studies, which reported reappraisal deficits in older children aged 10–17 with different anxiety disorders, including SAD [
7‐
9]. They also contrast with adult findings suggesting greater reappraisal-related brain activation in controls compared to adults with SAD [
66].
The absence of group differences in ERP reactivity and reappraisal modulation might be explained by changes in cognitive and neural development. Reappraisal-related neural activity may be influenced by brain maturation and associated increased cognitive control, working memory and cognitive flexibility [
23,
67]. Anatomically, emotion regulation is associated with activity in the prefrontal cortex [
68], which is one of the last brain structures to develop in adolescence [
69]. In the present study, the reappraisal-related LPP activity showed the expected direction only in the older group, which demonstrates that older children are able to accomplish this non-trivial cognitive operation. In line with this finding, several studies did not find reappraisal-induced LPP reductions in younger children aged 5–12 years [
22,
25,
56,
59,
70]. In considering these developmental aspects, it is conceivable that all young children, regardless of their level of anxiety, (a) display bottom-up driven biases towards threatening information [
71] and (b) do not show reappraisal modulation in neural components. With increasing age, non-anxious children might learn to inhibit automatic responding to threat by using top-down control strategies, whereas anxious children fail to do so [
71,
72]. This might result in group differences in emotional reactivity and regulation with increasing age. Indeed, a recent meta-analysis [
72] has found biased processing of threatening stimuli (i.e. enhanced emotional reactivity) in anxious children becomes more evident as children age. This is in accordance with another ERP study which found decreased LPP amplitudes in response to emotional faces with increasing age in controls, but not in SAD children [
16]. Possibly, clinical differences in emotional reactivity and reappraisal would only emerge in an adolescent or adult sample.
Reappraising Threatening Faces in Children: Gender Matters
We found gender effects on reappraisal and reactivity in both subjective and ERP responses. Compared to boys, girls showed higher subjective reactivity when interpreting angry children’s faces as socially threatening. Additionally, reappraisal-induced LPP reductions were present in boys but not in girls. Gender-related differences in emotional reactivity and regulation have been reported from previous studies with adult populations (e.g. [
73‐
76]. For example, in a study by McRae et al. [
35] men showed lower activity in brain regions related to the use of reappraisal such as the prefrontal cortex when compared to woman. On a subjective level, men and woman were equally able to reduce negative affect towards negative pictures through reappraisal. The authors speculate that male participants may require less cortical effort for the regulation of negative emotion, which would correspond to the findings of our study that only boys showed reappraisal effects on neural activity. Furthermore, girls have often been found to report higher reactivity to negative stimuli and greater difficulties regulating their negative emotions [
77‐
79]. These gender-related differences converge with higher prevalence rates of anxiety and mood disorders in girls [
80] suggesting a vulnerability for negative emotions and a difficulty to regulate these. There are also studies reporting gender differences on ERP measures: Girls showed enhanced LPPs to unpleasant and neutral versus pleasant stimuli while boys showed enhanced LPPs to pleasant versus neutral stimuli [
81]. Another ERP study showed reduced reappraisal effects on the LPP in younger girls [
21]. However, the underlying mechanisms of gender effects in children are still unknown and more research on this topic is clearly needed [
82]. A better understanding of gender-related differences in emotion regulation is crucial for informing theoretical models [
83], and therapeutic interventions, e.g. by addressing emotion regulation strategies specifically for boys versus girls [
77].
Limitations and Future Research
Our sample size did not allow for specific comparisons between single anxiety disorders (e.g. specific phobia vs. generalized anxiety disorder), which should be further investigated in future studies. Additionally, to evaluate age and gender effects in more detail, future research should include larger samples of girls and boys across a broad age range. Further, since we did not include a neutral baseline condition (e.g. observe, cf. [
44]), we do not know whether the subjective hyperreactivity in SAD was due to a generalized reactivity to any kind of social information or due to reporting biases. Last, we cannot rule out that children with SAD reported an elevated subjective reactivity in both conditions of our experiment due to a generally elevated emotional state [
84]. This would mean that also neutral and non-social stimuli could have led to reports of enhanced arousal (e.g. “How aroused would you feel if you were alone in your own room at home”). Future studies may therefore want to control for such effects using non-social control stimuli and situations.
In conclusion, the present findings indicate that children with SAD report enhanced subjective reactivity in response to angry children’s faces. It appears that LPP modulation can serve as a neural marker of cognitive reappraisal in older children and in boys, regardless of clinical anxiety. Importantly, while previous pediatric SAD research used adult faces, the present study extends previous findings to more salient peer stimuli. The absence of group differences in reappraisal suggests SAD children were just as effective at regulating as HC and MAD and that changing the affective meaning of social situations is something that patients and controls can accomplish. Thus, rather than addressing putative reappraisal deficits, therapeutic interventions in children with (social) anxiety disorders should target generalized hyperreactivity to social cues.