title: Subtypes of anhedonia and facial electromyography response to negative affective pictures in non-psychiatric adults.
abstract: BACKGROUND
  Flat/constricted affect and anhedonia are symptoms found in several psychiatric disorders such as depression and schizophrenia. However, there are very few studies on the relationships between specific anhedonia subtypes and objectively assessed flat affect, and it appears that none of the existing studies examined potential moderation by sex.
  
  
  METHODS
  Forty-seven undergraduate students (60% male) completed self-report questionnaires assessing three subtypes of anhedonia - non-social consummatory (CON) and anticipatory (ANT) anhedonia, and overall social anhedonia. Participants viewed 15 pictures (5 neutral and 10 negative) from the International Affective Picture System, whereas facial muscle reaction was recorded using electromyography (EMG).
  
  
  RESULTS
  Male participants reporting a greater level of overall social or non-social CON anhedonia showed a greater EMG activity increase in the corrugator supercilii muscle to negative (vs. neutral) pictures. In females, the relationship was only found with social anhedonia and was opposite in direction, as increased social anhedonia related to less EMG activity change in the corrugator muscle.
  
  
  CONCLUSIONS
  The relationship between anhedonia and flat affect varied as a function of sex and anhedonia subtype. These findings may help explain discrepancies in the sparse existing literature examining this relationship in psychiatric populations and have implications for assessment and treatment of these symptoms across psychiatric disorders.
authors.affiliation: a Psychology Department , University of Central Florida , 4111 Pictor Lane, Orlando, FL , USA.
authors.forename: L S
authors.initials: LS
authors.lastname: Kadison
authors.forename: K A
authors.initials: KA
authors.lastname: Ragsdale
authors.forename: J C
authors.initials: JC
authors.lastname: Mitchell
authors.forename: J E
authors.initials: JE
authors.lastname: Cassisi
authors.forename: J S
authors.initials: JS
authors.lastname: Bedwell
mesh_terms: D000293:Adolescent; D000339:Affect; D059445:Anhedonia / Q000145:classification*; D003863:Depression / Q000175:diagnosis; D004576:Electromyography; D005145:Face / Q000503:physiopathology*; D005149:Facial Expression; D005260:Female; D006801:Humans; D008297:Male; D012559:Schizophrenia / Q000175:diagnosis; D012737:Sex Factors; D013334:Students; D011795:Surveys and Questionnaires; D014481:United States; D014495:Universities; D055815:Young Adult
keywords: anhedonia; electromyography; emotion; expression; facial