Visual organization processes in schizophrenia.
Patients with schizophrenia are known to be impaired at organizing and exploring the visual environment. However, these impairments vary across studies, and the conditions determining whether patients are impaired or not are unclear. We aim to clarify this question by distinguishing different types of visual organization processes. A total of 23 patients and matched controls had to identify 2 identical figures embedded in a global structure made of connectors linking figures by pairs. The 2 targets belonged to either the same perceptual group (linked by a connector) or 2 different pairs (not linked by a connector). In a neutral condition, no connectors were presented. Top-down processes were explored by manipulating the proportion of targets linked or not by a connector in 3 experimental blocks. Patients needed the same processing time as controls to extract targets linked by a connector from the global structure. They could also focus on connectors when incited to do so. Impairments were observed for targets that were part of different pairs. Extracting such targets is effortful and time consuming, and both groups were slower in this condition than in the neutral condition. However, patients were slowed less than controls. This paradoxical improvement illustrates the fact that patients do not structure visual elements that are part of a global structure and not automatically bound together. Our results suggest this is due to impaired top-down processes.
van Assche
Mitsouko
M
INSERM U666, Department of Psychiatry, Centre Hospitalier Régional de Strasbourg, Strasbourg Cedex, France.
Giersch
Anne
A
D000328:Adult; D001245:Association Learning; D001288:Attention; D004192:Discrimination, Psychological; D005260:Female; D005364:Field Dependence-Independence; D006801:Humans; D008297:Male; D010364:Pattern Recognition, Visual; D010468:Perceptual Disorders / Q000175:diagnosis* / Q000523:psychology; D011930:Reaction Time; D012016:Reference Values; D014796:Visual Perception
Psychon Bull Rev. 1994 Mar;1(1):29-55
24203413
Psychiatry Res. 2006 Dec 7;145(2-3):105-17
17081620
Schizophr Res. 2000 May 25;43(1):11-20
10828411
J Abnorm Psychol. 1980 Jun;89(3):409-18
7410708
Int J Neuropsychopharmacol. 2006 Dec;9(6):695-704
16321171
Schizophr Bull. 1987;13(2):261-76
3616518
Psychol Bull. 2005 Jul;131(4):618-632
16060805
Schizophr Res. 2005 Jun 15;75(2-3):183-92
15885509
J Abnorm Psychol. 1996 Aug;105(3):410-20
8772011
Biol Psychiatry. 2002 Aug 15;52(4):338-48
12208641
Behav Brain Sci. 2003 Feb;26(1):65-82; discussion 82-137
14598440
Arch Gen Psychiatry. 2006 Dec;63(12):1313-23
17146006
Psychiatry Clin Neurosci. 2003 Aug;57(4):409-15
12839523
Schizophr Res. 2005 Apr 1;74(1):69-79
15694756
J Abnorm Psychol. 1984 May;93(2):231-4
6725757
Perception. 1994;23(4):399-409
7991341
Schizophr Res. 2007 Sep;95(1-3):205-14
17681736
Perception. 1988;17(2):229-47
3226865
Biol Psychiatry. 2003 Dec 1;54(11):1134-48
14643080
Schizophr Res. 1994 Sep;13(2):117-26
7986768
Biol Psychiatry. 2008 Jul 1;64(1):34-9
18374901
J Abnorm Psychol. 2008 Feb;117(1):132-42
18266491
Cogn Neuropsychol. 2000 Dec 1;17(8):731-59
20945203
J Exp Psychol Hum Percept Perform. 2002 Oct;28(5):1071-84
12421056
J Abnorm Psychol. 2001 Feb;110(1):67-75
11261402
Cogn Neuropsychiatry. 2008 Sep;13(5):385-405
18781493
J Abnorm Psychol. 1997 Nov;106(4):530-8
9358683
Vision Res. 1994 Dec;34(24):3361-9
7863619
Percept Psychophys. 2007 Jan;69(1):68-78
17515217
Cogn Neuropsychiatry. 2006 Mar;11(2):112-32
16537237
Acta Psychol (Amst). 1999 Mar;101(1):3-25
10100453
Schizophr Bull. 2007 Jan;33(1):142-56
17118973
Neurosci Lett. 2004 Mar 4;357(2):131-4
15036592