Children and adolescents with SP, GAD, or SAD, but not healthy youths, demonstrated an attention bias towards angry faces on a visual probe task. These results are consistent with several prior studies in anxious youth.26-30
The present results are also consistent with work in anxious adults, which reveals consistent evidence of attention biases towards threat words and angry faces.16,19,20
These findings support theories suggesting that anxious individuals manifest a selective processing bias towards threat5,6
due to a perturbation in neural mechanisms controlling vigilance.42
Of note, the current data differ from some other recent studies of anxious youth.11,31,32
For example, in the present study, healthy youths showed no attention bias towards angry faces, whereas this bias has been observed for other types of threat stimuli in healthy children (e.g., pictures of dogs, snakes, guns).31
Angry faces differ from threat pictures in several ways including emotional valence, subjective threat value, novelty, and complexity, all of which may impact attention processes.6
Moreover, two other studies, using the same visual probe paradigm employed in the current study, report an attention bias away
from angry faces in children and adolescents with either PTSD or GAD.11,32
Differences between the current results and these prior studies may reflect the differing circumstances across the three studies. For example, in Pine et al. 32
, the children experienced severe maltreatment and subsequent PTSD. One might expect that severely maltreated children might develop strong automatic tendencies to avoid angry faces, contributing to an attention bias away from threat. As such, the current data provide some support for distinctions between PTSD and other anxiety disorders based on information-processing profiles that may reflect differences in pathophysiology.43,44
Similarly, a recent functional magnetic resonance imaging study demonstrated an attention bias away from threat in adolescents with GAD.11
The anxiogenic environment of the MR scanner may have influenced the direction of the bias, leading to different results from those studies conducted in a laboratory or clinic. Research with anxious adults suggests that, under certain conditions, high levels of state anxiety may elicit cognitive suppression or avoidance responses that oppose attention biases towards threat.13,45
Therefore, the current results do not contradict these data, but rather highlight the sensitivity and variability in attention biases in pediatric samples under varying contexts. Additional research is needed specifically evaluating the effect of emotional and environmental factors on attention biases.
The findings from this study highlight the interactions between cognitive and emotional brain systems in the pathophysiology of anxiety disorders. An attention bias towards threat suggests that brain circuits mediating threat detection in anxious children may be hypersensitive.42
Consistent with this, neuroimaging studies of anxious children have demonstrated structural and functional abnormalities in regions implicated in emotion processing, including the amygdala and prefrontal cortex.9-12
It is still unknown whether these anxiety-related differences in brain anatomy and function precede or follow the development of anxiety disorders in youth. Further studies of attentional processes and associated neural activity using longitudinal and high-risk developmental designs are needed to answer these important etiological questions.
Continuous measures of anxiety did not correlate with attention bias, which contrasts the findings of Waters et al. (in press), who found positive relationships between parental report of child anxiety severity and attention bias for happy and angry faces in children with GAD. While these studies used the same attention task, the sample in Waters et al. was younger (ages 7 – 12 years) than the present one, and the studies used different measures of anxiety symptoms, limiting direct comparison of results. In the present study, attention bias measures did not differ among the three anxiety disorders. However, high comorbidity complicated efforts to isolate associations with one or another anxiety disorder. Studies of children with single anxiety disorder diagnoses might reveal specific associations, though the generalizability of such studies would be limited given the high rates at which anxiety disorders co-occur in clinical samples.46
The current findings should be evaluated in light of study limitations. First, while the multi-site design of the CAMS study allowed us to recruit a very large sample of anxiety-disordered youth, it may also have increased the variability of the data because environmental conditions could not be precisely controlled across the seven study sites. However, no site differences (all F-values <1) were found for the primary dependent measures of threat or happy bias in either the anxious or healthy youths. Second, the anxious and healthy groups were not matched on age, race, IQ, or mean RT during neutral trials. After controlling for these variables, the group difference in threat bias remained, albeit at a lower statistical threshold. This likely reflects reduced statistical power caused by the inclusion of multiple covariates that were not associated with the dependent variable. Replication with more closely matched samples is needed to test the reliability of the group differences we observed. Third, the magnitude of between-group differences was not large, in terms of absolute milliseconds or effect size. Nevertheless, the magnitude found here replicates that in prior studies, suggesting that differences are reliably detectable with appropriately-powered studies.
Overall, the present study provides support for the relationship between pediatric anxiety and attention bias towards threat. Further research is needed to evaluate the robustness of this association and the specific circumstances that influence it. Additionally, unanswered questions remain regarding the role of this bias in the etiology or maintenance of these disorders, as well as how it may relate to treatment response. Analysis of the visual probe data collected during the treatment and outcome phases of the CAMS study will provide an opportunity to examine the latter question. However, longitudinal studies are needed to examine the specificity of these attentional processes and their role in the development of pediatric anxiety disorders and subsequent mood and anxiety disorders in adulthood.