title: Successful measurement of the mismatch negativity despite a concurrent movie soundtrack: reduced amplitude but normal component morphology.
abstract: OBJECTIVE
  To examine the mechanisms responsible for the reduction of the mismatch negativity (MMN) ERP component observed in response to pitch changes when the soundtrack of a movie is presented while recording the MMN.
  
  
  METHODS
  In three experiments we measured the MMN to tones that differed in pitch from a repeated standard tone presented with a silent subtitled movie, with the soundtrack played forward or backward, or with soundtracks set at different intensity levels.
  
  
  RESULTS
  MMN amplitude was reduced when the soundtrack was presented either forward or backward compared to the silent subtitled movie. With the soundtrack, MMN amplitude increased proportionally to the increments in the sound-to-noise intensity ratio.
  
  
  CONCLUSIONS
  MMN was reduced in amplitude but had normal morphology with a concurrent soundtrack, most likely because of basic acoustical interference from the soundtrack with MMN-critical tones rather than from attentional effects.
  
  
  CONCLUSIONS
  A normal MMN can be recorded with a concurrent movie soundtrack, but signal amplitudes need to be set with caution to ensure a sufficiently high sound-to-noise ratio between MMN stimuli and the soundtrack.
authors.affiliation: International Laboratory for Brain, Music, and Sound Research (BRAMS), Department of Psychology, University of Montreal, Canada. Electronic address: patricia.moreau@hotmail.com.
authors.forename: Patricia
authors.initials: P
authors.lastname: Moreau
authors.forename: Pierre
authors.initials: P
authors.lastname: Jolicœur
authors.forename: Pascale
authors.initials: P
authors.lastname: Lidji
authors.forename: Isabelle
authors.initials: I
authors.lastname: Peretz
mesh_terms: D000161:Acoustic Stimulation; D000328:Adult; D000704:Analysis of Variance; D001288:Attention / Q000502:physiology*; D004569:Electroencephalography; D005072:Evoked Potentials, Auditory / Q000502:physiology*; D005260:Female; D006801:Humans; D007802:Language; D008297:Male; D009040:Motion Pictures; D010470:Perceptual Masking / Q000502:physiology*; D010897:Pitch Discrimination / Q000502:physiology*; D011930:Reaction Time; D055815:Young Adult
keywords: Attention; Auditory ERP; Masking noise; Mismatch negativity; Movie soundtrack; Pitch