title: Neuroimaging evidence of cerebellar involvement in premenstrual dysphoric disorder.
abstract: BACKGROUND
  Premenstrual dysphoric disorder (PMDD) is a debilitating cyclic disorder that is characterized by affective symptoms, including irritability, depression, and anxiety, which arise in the luteal phase of the menstrual cycle and resolve soon after the onset of menses. Despite a prevalence of up to 8% in women of reproductive age, few studies have investigated the brain mechanisms that underlie this disorder.
  
  
  METHODS
  We used positron emission tomography with [(18)F] fluorodeoxyglucose and self-report questionnaires to assess cerebral glucose metabolism and mood in 12 women with PMDD and 12 healthy comparison subjects in the follicular and late luteal phases of the menstrual cycle. The primary biological end point was incorporated regional cerebral radioactivity (scaled to the global mean) as an index of glucose metabolism. Relationships between regional brain activity and mood ratings were assessed. Blood samples were taken before each session for assay of plasma estradiol and progesterone concentrations.
  
  
  RESULTS
  There were no group differences in hormone levels in either the follicular or late luteal phase, but the groups differed in the effect of menstrual phase on cerebellar activity. Women with PMDD but not comparison subjects showed an increase in cerebellar activity (particularly in the right cerebellar vermis) from the follicular phase to the late luteal phase (p = .003). In the PMDD group, this increase in cerebellar activity was correlated with worsening of mood (p = .018).
  
  
  CONCLUSIONS
  These findings suggest that the midline cerebellar nuclei, which have been implicated in other mood disorders, also contribute to negative mood in PMDD.
authors.affiliation: Department of Obstetrics and Gynecology, David Geffen School of Medicine at University of California at Los Angeles, Los Angeles, California 90095-1740, USA. arapkin@mednet.ucla.edu
authors.forename: Andrea J
authors.initials: AJ
authors.lastname: Rapkin
authors.forename: Steven M
authors.initials: SM
authors.lastname: Berman
authors.forename: Mark A
authors.initials: MA
authors.lastname: Mandelkern
authors.forename: Daniel H S
authors.initials: DH
authors.lastname: Silverman
authors.forename: Melinda
authors.initials: M
authors.lastname: Morgan
authors.forename: Edythe D
authors.initials: ED
authors.lastname: London
mesh_terms: D000293:Adolescent; D000328:Adult; D000339:Affect; D000704:Analysis of Variance; D002531:Cerebellum / Q000000981:diagnostic imaging*; D004958:Estradiol / Q000097:blood; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008597:Menstrual Cycle / Q000097:blood; D049268:Positron-Emission Tomography; D011293:Premenstrual Syndrome / Q000000981:diagnostic imaging* / Q000523:psychology; D011374:Progesterone / Q000097:blood; D011795:Surveys and Questionnaires
chemical_list: D011374:Progesterone; D004958:Estradiol