title: Brain substrates of perceived spatial separation between speech sources under simulated reverberant listening conditions in schizophrenia.
abstract: BACKGROUND
  People with schizophrenia recognize speech poorly under multiple-people-talking (informational masking) conditions. In reverberant environments, direct-wave signals from a speech source are perceptually integrated with the source reflections (the precedence effect), forming perceived spatial separation (PSS) between different sources and consequently improving target-speech recognition against informational masking. However, the brain substrates underlying the schizophrenia-related vulnerability to informational masking and whether schizophrenia affects the unmasking effect of PSS are largely unknown.
  
  
  METHODS
  Using psychoacoustic testing and functional magnetic resonance imaging, respectively, the speech recognition under either the PSS or perceived spatial co-location (PSC) condition and the underlying brain substrates were examined in 20 patients with schizophrenia and 16 healthy controls.
  
  
  RESULTS
  Speech recognition was worse in patients than controls. Under the PSS (but not PSC) condition, speech recognition was correlated with activation of the superior parietal lobule (SPL), and target speech-induced activation of the SPL, precuneus, middle cingulate cortex and caudate significantly declined in patients. Moreover, the separation (PSS)-against-co-location (PSC) contrast revealed (1) activation of the SPL, precuneus and anterior cingulate cortex in controls, (2) suppression of the SPL and precuneus in patients, (3) activation of the pars triangularis of the inferior frontal gyrus and middle frontal gyrus in both controls and patients, (4) activation of the medial superior frontal gyrus in patients, and (5) impaired functional connectivity of the SPL in patients.
  
  
  CONCLUSIONS
  Introducing the PSS listening condition efficiently reveals both the brain substrates underlying schizophrenia-related speech-recognition deficits against informational masking and the schizophrenia-related neural compensatory strategy for impaired SPL functions.
authors.affiliation: Guangzhou Brain Hospital, the Affiliated Hospital of Guangzhou Medical University,Guangzhou 510370,People's Republic of China.
authors.forename: Y
authors.initials: Y
authors.lastname: Zheng
authors.affiliation: Department of Psychology,School of Life Sciences,McGovern Institute for Brain Research at PKU,Key Laboratory on Machine Perception (Ministry of Education),Peking University,Beijing 100871,People's Republic of China.
authors.forename: C
authors.initials: C
authors.lastname: Wu
authors.affiliation: Guangzhou Brain Hospital, the Affiliated Hospital of Guangzhou Medical University,Guangzhou 510370,People's Republic of China.
authors.forename: J
authors.initials: J
authors.lastname: Li
authors.affiliation: Guangzhou Brain Hospital, the Affiliated Hospital of Guangzhou Medical University,Guangzhou 510370,People's Republic of China.
authors.forename: H
authors.initials: H
authors.lastname: Wu
authors.affiliation: Guangzhou Brain Hospital, the Affiliated Hospital of Guangzhou Medical University,Guangzhou 510370,People's Republic of China.
authors.forename: S
authors.initials: S
authors.lastname: She
authors.affiliation: Guangzhou Brain Hospital, the Affiliated Hospital of Guangzhou Medical University,Guangzhou 510370,People's Republic of China.
authors.forename: S
authors.initials: S
authors.lastname: Liu
authors.affiliation: Department of Psychology,School of Life Sciences,McGovern Institute for Brain Research at PKU,Key Laboratory on Machine Perception (Ministry of Education),Peking University,Beijing 100871,People's Republic of China.
authors.forename: L
authors.initials: L
authors.lastname: Mao
authors.affiliation: Guangzhou Brain Hospital, the Affiliated Hospital of Guangzhou Medical University,Guangzhou 510370,People's Republic of China.
authors.forename: Y
authors.initials: Y
authors.lastname: Ning
authors.affiliation: Department of Psychology,School of Life Sciences,McGovern Institute for Brain Research at PKU,Key Laboratory on Machine Perception (Ministry of Education),Peking University,Beijing 100871,People's Republic of China.
authors.forename: L
authors.initials: L
authors.lastname: Li
mesh_terms: D000293:Adolescent; D000328:Adult; D001288:Attention / Q000502:physiology; D001307:Auditory Perception / Q000502:physiology*; D001931:Brain Mapping; D016022:Case-Control Studies; D002681:China; D005260:Female; D005625:Frontal Lobe / Q000503:physiopathology; D006179:Gyrus Cinguli / Q000503:physiopathology; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D010296:Parietal Lobe / Q000503:physiopathology; D010470:Perceptual Masking / Q000502:physiology*; D012559:Schizophrenia / Q000503:physiopathology*; D013067:Speech Perception / Q000502:physiology*; D055815:Young Adult
keywords: Neural compensation; precedence effect; precuneus; schizophrenia; spatial attention; speech recognition; superior parietal lobule