title: An investigation of semantic space in patients with schizophrenia.
abstract: There has been increasing interest in the semantic cognitive system in schizophrenia. Recent findings suggest a possible breakdown of semantic information processing in this disorder. The current study attempts to further examine semantic organization in schizophrenia. Twenty-eight chronic, early-onset schizophrenic patients and 32 controls were matched for premorbid intelligence and compared in their ability to spontaneously cluster exemplars from a specific category during a fluency task. Using multidimensional scaling and clustering techniques, 11 exemplars occurring most frequently in both groups were chosen for examination of their relative "proximity" during word generation. Patients with schizophrenia showed a less stable two-dimensional organization of exemplars and were less likely to group exemplars into subordinate clusters than were normals. These results suggest that semantic networks are disorganized in these patients. These findings may have some implications for the debate over the origin of "thought disorder" in schizophrenia.
authors.affiliation: Clinical Brain Disorders Branch, National Institute of Mental Health, Neuroscience Center at St. Elizabeths, Washington, DC 20032, USA.
authors.forename: M S
authors.initials: MS
authors.lastname: Aloia
authors.forename: M L
authors.initials: ML
authors.lastname: Gourovitch
authors.forename: D R
authors.initials: DR
authors.lastname: Weinberger
authors.forename: T E
authors.initials: TE
authors.lastname: Goldberg
mesh_terms: D000328:Adult; D002908:Chronic Disease; D003210:Concept Formation; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010153:Paired-Associate Learning; D012559:Schizophrenia / Q000175:diagnosis*; D012564:Schizophrenic Language; D012660:Semantics; D013850:Thinking; D014705:Verbal Behavior