title: Brain activity during expectancy of emotional stimuli: an fMRI study.
abstract: We studied the neural activation associated with the expectancy of emotional stimuli using whole brain fMRI. Fifteen healthy subjects underwent fMRI scanning during which they performed a warned reaction task using emotional pictures carrying pleasant, unpleasant, or neutral content. The task involved an expected or unexpected condition. Data were analyzed by comparing the images acquired under the different conditions. In the expected condition, compared with the unexpected condition, significant activation was observed in the medial, inferior and dorsolateral prefrontal cortex. Whereas the expectancy of pleasant stimuli produced activation in the left dorsolateral and left medial prefrontal cortex as well as in the right cerebellum, the expectancy of unpleasant stimuli produced activation in the right inferior and right medial prefrontal cortex, the right amygdala, the left anterior cingulate cortex, and bilaterally in the visual cortex. These results suggest that the expectancy of emotional stimuli is mediated by the prefrontal area including the medial, inferior, and dorsolateral prefrontal cortex. Furthermore, our data suggest that left frontal activation is associated with the expectancy of pleasant stimuli and that right frontal activation is associated with the expectancy of unpleasant stimuli. Finally, our findings suggest that the amygdala and anterior cingulate cortex may play an important role in the expectancy of unpleasant stimuli and that the input of this negative information is modulated by these specific brain areas.
authors.affiliation: Department of Psychiatry and Neurosciences, Division of Frontier Medical Science, Programs for Biomedical Research, Graduate School of Biomedical Sciences, Hiroshima University, 1-2-3, Kasumi, Minami-ku, Hiroshima 734-8551, Japan.
authors.forename: Kazutaka
authors.initials: K
authors.lastname: Ueda
authors.forename: Yasumasa
authors.initials: Y
authors.lastname: Okamoto
authors.forename: Go
authors.initials: G
authors.lastname: Okada
authors.forename: Hidehisa
authors.initials: H
authors.lastname: Yamashita
authors.forename: Tadao
authors.initials: T
authors.lastname: Hori
authors.forename: Shigeto
authors.initials: S
authors.lastname: Yamawaki
mesh_terms: D000328:Adult; D000679:Amygdala / Q000502:physiology; D001931:Brain Mapping; D002531:Cerebellum / Q000502:physiology; D003214:Conditioning, Classical / Q000502:physiology*; D004644:Emotions / Q000502:physiology*; D005260:Female; D005625:Frontal Lobe / Q000502:physiology; D006179:Gyrus Cinguli / Q000502:physiology; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D010775:Photic Stimulation; D017397:Prefrontal Cortex / Q000502:physiology; D014793:Visual Cortex / Q000502:physiology