title: Verbal working memory in schizophrenia: The role of syntax in facilitating serial recall.
abstract: Deficits in verbal working memory (VWM) have consistently been observed in schizophrenia, ranging from impairments in capacity, encoding, to irregular semantic organisation. However, syntactic deficits are less well-characterised, despite its crucial role in language construction. This study examines the role of simple syntactic structure (basis of the "sentence superiority effect") in VWM of patients with psychotic disorders.
  
  
  
  Patients with schizophrenia-spectrum disorders (n=40) and healthy controls matched on age, sex and education (n=40) were administered an auditory serial recall task containing word lists with low semantic coherence and either syntactically familiar structure (noun-verb-noun sequence) or syntactically unfamiliar structure. Other neurocognitive measures, symptoms and social functioning of patients were also assessed.
  
  
  
  A 4-way analysis of variance (group×version×list type×serial position) indicated that patients had significantly worse performance overall, suggesting a generalised verbal memory impairment. In addition, a significant interaction was found for list type and Group, demonstrating that healthy controls, but not patients, had superior performance in syntactically familiar word lists. A subgroup analysis of high-performing patients revealed that the interaction was not an artefact of poor verbal memory, but a selective deficit in syntactic facilitation.
  
  
  
  Our findings may suggest segregated mechanisms for maintenance and computational aspects of VWM, and show that even simple syntactic structure facilitates recall of syntactically unfamiliar words lists. Additionally, schizophrenic patients show difficulty utilising syntactic information, which highlights the need to understand the neuropsychological basis of working memory and linguistic impairments in psychosis.
authors.affiliation: Department of Psychiatry, University of Hong Kong, Queen Mary Hospital, 102 Pokfulam Road, Hong Kong, China. Electronic address: adrienne.li.15@ucl.ac.uk.
authors.forename: Adrienne W Y
authors.initials: AWY
authors.lastname: Li
authors.affiliation: Centre for Brain and Education. Department of Education and Human Development, The Education University of Hong Kong, 10 Lo Ping Road, Tai Po N.T., Hong Kong, China.
authors.forename: Nestor
authors.initials: N
authors.lastname: Viñas-Guasch
authors.affiliation: Department of Psychiatry, University of Hong Kong, Queen Mary Hospital, 102 Pokfulam Road, Hong Kong, China.
authors.forename: Christy L M
authors.initials: CLM
authors.lastname: Hui
authors.affiliation: Department of Psychiatry, University of Hong Kong, Queen Mary Hospital, 102 Pokfulam Road, Hong Kong, China.
authors.forename: Wing-Chung
authors.initials: WC
authors.lastname: Chang
authors.affiliation: Department of Psychiatry, University of Hong Kong, Queen Mary Hospital, 102 Pokfulam Road, Hong Kong, China.
authors.forename: Sherry K W
authors.initials: SKW
authors.lastname: Chan
authors.affiliation: Department of Psychiatry, University of Hong Kong, Queen Mary Hospital, 102 Pokfulam Road, Hong Kong, China.
authors.forename: Edwin H M
authors.initials: EHM
authors.lastname: Lee
authors.affiliation: Department of Psychiatry, University of Hong Kong, Queen Mary Hospital, 102 Pokfulam Road, Hong Kong, China; State Key Laboratory of Brain and Cognitive Sciences, University of Hong Kong, 5 Sassoon Road, Hong Kong, China.
authors.forename: Eric Y H
authors.initials: EYH
authors.lastname: Chen
mesh_terms: D000293:Adolescent; D000328:Adult; D003072:Cognition Disorders / Q000175:diagnosis / Q000209:etiology; D005260:Female; D006801:Humans; D008297:Male; D008569:Memory Disorders / Q000209:etiology*; D008570:Memory, Short-Term / Q000502:physiology*; D011939:Mental Recall / Q000502:physiology*; D009483:Neuropsychological Tests; D011569:Psychiatric Status Rating Scales; D012559:Schizophrenia / Q000150:complications*; D012565:Schizophrenic Psychology; D012660:Semantics; D012691:Serial Learning / Q000502:physiology*; D018709:Statistics, Nonparametric; D014706:Verbal Learning / Q000502:physiology*; D014825:Vocabulary; D055815:Young Adult
keywords: Cognition; Language; Psychosis; Syntax; Working memory