title: Using arterial spin labeling to examine mood states in youth.
abstract: BACKGROUND
  Little is known about the neural correlates of mood states and the specific physiological changes associated with their valence and duration, especially in young people. Arterial spin labeling (ASL) imaging is particularly well-suited to study sustained cerebral states in young people, due to its robustness to low-frequency drift, excellent interscan reliability, and noninvasiveness. Yet, it has so far been underutilized for understanding the neural mechanisms underlying mood states in youth.
  
  
  METHODS
  In this exploratory study, 21 healthy adolescents aged 16 to 18 took part in a mood induction experiment. Neutral, sad, and happy mood states were induced using film clips and explicit instructions. An ASL scan was obtained following presentation of each film clip.
  
  
  RESULTS
  Mood induction led to robust changes in self-reported mood ratings. Compared to neutral, sad mood was associated with increased regional cerebral blood flow (rCBF) in the left middle frontal gyrus and anterior prefrontal cortex, and decreased rCBF in the right middle frontal gyrus and the inferior parietal lobule. A decrease in self-reported mood from neutral to sad condition was associated with increased rCBF in the precuneus. Happy mood was associated with increased rCBF in medial frontal and cingulate gyri, the subgenual anterior cingulate cortex, and ventral striatum, and decreased rCBF in the inferior parietal lobule. The level of current self-reported depressive symptoms was negatively associated with rCBF change in the cerebellum and lingual gyrus following both sad and happy mood inductions.
  
  
  CONCLUSIONS
  Arterial spin labeling is sensitive to experimentally induced mood changes in healthy young people. The effects of happy mood on rCBF patterns were generally stronger than the effects of sad mood.
authors.affiliation: Department of Child and Adolescent Psychiatry, King's College London, Institute of Psychiatry, Psychology & Neuroscience London, UK.
authors.forename: Nina
authors.initials: N
authors.lastname: Mikita
authors.affiliation: Centre for Neuroimaging Sciences, King's College London, Institute of Psychiatry, Psychology & Neuroscience London, UK.
authors.forename: Mitul A
authors.initials: MA
authors.lastname: Mehta
authors.affiliation: Centre for Neuroimaging Sciences, King's College London, Institute of Psychiatry, Psychology & Neuroscience London, UK.
authors.forename: Fernando O
authors.initials: FO
authors.lastname: Zelaya
authors.affiliation: Department of Child and Adolescent Psychiatry, King's College London, Institute of Psychiatry, Psychology & Neuroscience London, UK.
authors.forename: Argyris
authors.initials: A
authors.lastname: Stringaris
mesh_terms: D000293:Adolescent; D000294:Adolescent Behavior / Q000502:physiology / Q000523:psychology; D000339:Affect / Q000502:physiology*; D002560:Cerebrovascular Circulation / Q000502:physiology*; D005260:Female; D006240:Happiness; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D055420:Perfusion Imaging / Q000379:methods; D000297:Psychology, Adolescent / Q000379:methods; D015203:Reproducibility of Results
keywords: Adolescents; happiness; mood; perfusion magnetic resonance imaging