Dissection of early bottom-up and top-down deficits during visual attention in schizophrenia.
OBJECTIVE
To characterize the interplay of bottom-up and top-down processing deficits of the early visual ERP component N1 in schizophrenia.


METHODS
Thirty-three schizophrenic patients and 61 healthy controls underwent a visual selective attention paradigm while 32-channel electroencephalogram was recorded. Visual N1 responses were calculated and source localization was applied.


RESULTS
Significant reductions of the cue N1 as well as the target N1 components were found in schizophrenia patients. Linear regression slopes for the cue N1 and for the cue-locked target N1 indicated significantly reduced early bottom-up and top-down modulation in patients relative to controls. Source analyses indicated that bottom-up as well as top-down N1 deficits in schizophrenia are associated with partially overlapping current density deficits in posterior cortex areas. Differential functional deficits were observed in right parietal lobe during bottom-up processing and in anterior cingulate cortex during top-down attention.


CONCLUSIONS
The results provide evidence for both early visual bottom-up and top-down deficits in schizophrenia and illustrate how disturbances in these processing streams converge on the visual N1 amplitude.


CONCLUSIONS
Visual top-down disturbances in schizophrenia appear to be confounded by visual bottom-up deficits.
Neuhaus
Andres H
AH
Department of Psychiatry and Psychotherapy, Charité University Medicine, Campus Benjamin Franklin, Berlin, Germany. andres.neuhaus@charite.de
Karl
Christine
C
Hahn
Eric
E
Trempler
Niklas R
NR
Opgen-Rhein
Carolin
C
Urbanek
Carsten
C
Hahn
Constanze
C
Ta
Thi Minh Tam
TM
Dettling
Michael
M
D000293:Adolescent; D000328:Adult; D000368:Aged; D001288:Attention / Q000502:physiology*; D002540:Cerebral Cortex / Q000033:anatomy & histology / Q000503:physiopathology*; D005071:Evoked Potentials / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests / Q000592:standards; D010468:Perceptual Disorders / Q000175:diagnosis / Q000209:etiology / Q000503:physiopathology*; D012559:Schizophrenia / Q000150:complications / Q000175:diagnosis / Q000503:physiopathology*; D014796:Visual Perception / Q000502:physiology*; D055815:Young Adult