title: Lateralized perceptual organization deficits on the global-local task in schizotypal personality disorder.
abstract: Right and left hemisphere contributions to perceptual organization functions were examined using a divided-attention version of the global-local task in a sample of 21 unmedicated participants diagnosed with schizotypal personality disorder (SPD) and 20 controls. The SPD participants showed an abnormal global processing advantage. When the visual angle of the hierarchical stimuli was increased from 3 degrees to 9 degrees, the controls showed an increasing local processing advantage, but the SPD participants continued to show an abnormal global processing advantage. These findings suggest a local processing deficit on divided-attention versions of the global-local task in schizophrenia spectrum disorders. Female SPD participants, who had less severe interpersonal deficit symptoms, showed a more abnormal global processing advantage. Hemispheric and processing resource mechanisms that might explain these findings are discussed.
authors.affiliation: Psychology Service, Veterans Affairs San Diego Healthcare System, California 92161, USA. egranholm@ucsd.edu
authors.forename: Eric
authors.initials: E
authors.lastname: Granholm
authors.forename: Kristin
authors.initials: K
authors.lastname: Cadenhead
authors.forename: Kathleen M
authors.initials: KM
authors.lastname: Shafer
authors.forename: J Vincent
authors.initials: JV
authors.lastname: Filoteo
mesh_terms: D000328:Adult; D001921:Brain / Q000503:physiopathology*; D005260:Female; D007839:Functional Laterality / Q000502:physiology*; D006801:Humans; D008297:Male; D010468:Perceptual Disorders / Q000150:complications*; D011930:Reaction Time; D012569:Schizotypal Personality Disorder / Q000150:complications* / Q000503:physiopathology*