title: Isolating neural components of threat bias in pediatric anxiety.
abstract: BACKGROUND
  Attention biases toward threat are often detected in individuals with anxiety disorders. Threat biases can be measured experimentally through dot-probe paradigms, in which individuals detect a probe following a stimulus pair including a threat. On these tasks, individuals with anxiety tend to detect probes that occur in a location previously occupied by a threat (i.e., congruent) faster than when opposite threats (i.e., incongruent). In pediatric anxiety disorders, dot-probe paradigms detect abnormal attention biases toward threat and abnormal ventrolateral prefrontal cortex (vlPFC) function. However, it remains unclear if this aberrant vlPFC activation occurs while subjects process threats (e.g., angry faces) or, alternatively, while they process and respond to probes. This magnetoencephalography (MEG) study was designed to answer this question.
  
  
  METHODS
  Adolescents with either generalized anxiety disorder (GAD, n = 17) or no psychiatric diagnosis (n = 25) performed a dot-probe task involving angry and neutral faces while MEG data were collected. Synthetic Aperture Magnetometry (SAM) beamformer technique was used to determine whether there were group differences in power ratios while subjects processed threats (i.e., angry vs. neutral faces) or when subjects responded to incongruent versus. congruent probes.
  
  
  RESULTS
  Group differences in vlPFC activation during the response period emerged with a 1-30 Hz frequency band. No group differences in vlPFC activation were detected in response to angry-face cues.
  
  
  CONCLUSIONS
  In the dot-probe task, anxiety-related perturbations in vlPFC activation reflect abnormal attention control when responding to behaviorally relevant probes, but not to angry faces. Given that motor responses to these probes are used to calculate threat bias, this study provides insight into the pathophysiology reflected in this commonly used marker of anxiety. In addition, this finding may inform the development of novel anxiety-disorder treatments targeting the vlPFC to enhance attention control to task-relevant demands.
authors.affiliation: Section on Development and Affective Neuroscience, National Institute of Mental Health, 9000 Rockville Pike, Bethesda, MD 20892, USA. brittonjen@mail.nih.gov
authors.forename: Jennifer C
authors.initials: JC
authors.lastname: Britton
authors.forename: Yair
authors.initials: Y
authors.lastname: Bar-Haim
authors.forename: Frederick W
authors.initials: FW
authors.lastname: Carver
authors.forename: Tom
authors.initials: T
authors.lastname: Holroyd
authors.forename: Maxine A
authors.initials: MA
authors.lastname: Norcross
authors.forename: Allison
authors.initials: A
authors.lastname: Detloff
authors.forename: Ellen
authors.initials: E
authors.lastname: Leibenluft
authors.forename: Monique
authors.initials: M
authors.lastname: Ernst
authors.forename: Daniel S
authors.initials: DS
authors.lastname: Pine
mesh_terms: D000293:Adolescent; D000786:Anger; D001007:Anxiety / Q000473:pathology*; D001288:Attention; D016022:Case-Control Studies; D002648:Child; D004924:Escape Reaction / Q000502:physiology; D005149:Facial Expression; D005260:Female; D006801:Humans; D015225:Magnetoencephalography; D008297:Male; D017397:Prefrontal Cortex / Q000473:pathology*; D014481:United States