title: Neural substrates of emotion as revealed by functional magnetic resonance imaging.
abstract: OBJECTIVE
  To examine the brain circuitry involved in emotional experience and determine whether the cerebral hemispheres are specialized for positive and negative emotional experience.
  
  
  BACKGROUND
  Recent research has provided a preliminary sketch of the neurologic underpinnings of emotional processing involving specialized contributions of limbic and cortical brain regions. Electrophysiologic, functional imaging, and Wada test data have suggested positive, approach-related emotions are associated with left cerebral hemisphere regions, whereas negative, withdrawal-related emotions appear to be more aligned with right hemisphere mechanisms.
  
  
  METHODS
  These emotional-neural associations were investigated using functional magnetic resonance imaging in 10 healthy controls with 20 positively and 20 negatively valenced pictures from the International Affective Picture System in a counterbalanced order. Pictures were viewed within a 1.5 Telsa scanner through computerized video goggles.
  
  
  RESULTS
  Emotional pictures resulted in significantly increased blood flow bilaterally in the mesial frontal lobe/anterior cingulate gyrus, dorsolateral frontal lobe, amygdala/anterior temporal regions, and cerebellum. Negative emotional pictures resulted in greater activation of the right hemisphere, and positive pictures caused greater activation of the left hemisphere.
  
  
  CONCLUSIONS
  Results are consistent with theories emphasizing the importance of circuitry linking subcortical structures with mesial temporal, anterior cingulate, and frontal lobe regions in emotion and with the valence model of emotion that posits lateralized cerebral specialization for positive and negative emotional experience.
authors.affiliation: Department of Neurology, Medical College of Georgia, Augusta, Georgia 30912-3275, USA. glee@mail.mcg.edu
authors.forename: Gregory P
authors.initials: GP
authors.lastname: Lee
authors.forename: Kimford J
authors.initials: KJ
authors.lastname: Meador
authors.forename: David W
authors.initials: DW
authors.lastname: Loring
authors.forename: Jerry D
authors.initials: JD
authors.lastname: Allison
authors.forename: Warren S
authors.initials: WS
authors.lastname: Brown
authors.forename: Lynn K
authors.initials: LK
authors.lastname: Paul
authors.forename: Jay J
authors.initials: JJ
authors.lastname: Pillai
authors.forename: Thomas B
authors.initials: TB
authors.lastname: Lavin
mesh_terms: D000328:Adult; D002540:Cerebral Cortex / Q000098:blood supply* / Q000502:physiology*; D004644:Emotions; D005260:Female; D007839:Functional Laterality; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged