title: Electrophysiological index of acoustic temporal regularity violation in the middle latency range.
abstract: OBJECTIVE
  Acoustic violations in temporal regularity have been traditionally indexed by mismatch negativity (MMN). However, recent studies have demonstrated that humans can detect auditory changes in physical sound features, such as frequency, location and intensity, in the first 50 ms after sound onset. Our aim was to examine if temporal regularity violations could be detected in the middle latency range.
  
  
  METHODS
  We used an oddball paradigm with 290 ms as standard stimulus onset asynchrony (SOA) and 200 ms as deviant SOA. We also employed a control paradigm that comprised of seven SOAs including 200 and 290 ms, in order to control for differences due to refractoriness.
  
  
  RESULTS
  In the middle latency range, temporal regularity violations led to enhanced Pa and Nb responses, which behaved differently to the corresponding SOAs in the control condition. In the long latency range, temporal regularity violations led to similar behaviours in both oddball and control paradigms.
  
  
  CONCLUSIONS
  These findings suggest that with a fast presentation rate, human brains are capable to detect temporal regularity violations in the middle latency range.
  
  
  CONCLUSIONS
  Together with previous studies that found early change detection responses, the current study emphasises that the human brain can encode simple regularity violation as early as approximately 50 ms post-stimulus onset.
authors.affiliation: Institute for Brain, Cognition and Behavior (IR3C), University of Barcelona, Catalonia, Spain; Cognitive Neuroscience Research Group, Department of Psychiatry and Clinical Psychobiology, University of Barcelona, Catalonia, Spain.
authors.forename: Sumie
authors.initials: S
authors.lastname: Leung
authors.forename: Marc
authors.initials: M
authors.lastname: Recasens
authors.forename: Sabine
authors.initials: S
authors.lastname: Grimm
authors.forename: Carles
authors.initials: C
authors.lastname: Escera
mesh_terms: D000161:Acoustic Stimulation; D000293:Adolescent; D000328:Adult; D001307:Auditory Perception / Q000502:physiology*; D004569:Electroencephalography; D005260:Female; D006801:Humans; D008297:Male; D010507:Periodicity; D011930:Reaction Time; D013016:Sound; D055815:Young Adult
keywords: Auditory processing; Deviance detection; Middle latency response; Mismatch negativity (MMN); Stimulus onset asynchrony (SOA); Temporal regularity