Preattentional processes and disorganization in schizophrenia: Influence of a 6-week risperidone treatment.
BACKGROUND
Visual orientation and attention are impaired in schizophrenia. Engagement and disengagement of attention and the ability to prompt responses to a stimulus in patients before and after six weeks of risperidone were compared to controls.


METHODS
Ten unmedicated (nine naïve) schizophrenic patients, and eleven controls performed 1) A visual orienting task, the Cued Target Detection task (CTD), with the detection of a visual stimulus in valid, invalid, no cue and double cue trials, two conditions for fixation offset for a modulation of visual fixation: Gap: 200 ms before target; No Gap: simultaneous with target, 2) Choice Reaction Time (CRT 0.5 and 2 s delays).


RESULTS
At baseline, patients showed longer RT than controls in CRT, but not in CTD, with in CTD, no facilitation of RT with the gap procedure. The alertness index was almost null in CTD-Gap and comparable to controls in CTD-No Gap. Efficiency to detect attended stimuli (CTD-No Gap) and warning effect (CRT 0.5 s) were negatively correlated to disorganization. After treatment, readiness to act in CRT had decreased. In CTD-No Gap, change in PANSS disorganization was correlated to an increased validity index, change in negative sub-score was correlated to decreased attention cost.


CONCLUSIONS
Untreated patients displayed a deficit of Gap effect and a slowing in sustained attention. Disorganization interfered with warning and visual detection. After treatment, its improvement and negative symptoms improvement were associated with better visual detection. These alterations in visual orienting provide new evidence for an oculomotor dysregulation of attentional engagement in schizophrenia.
Amado
I
I
INSERM U796, Faculté Paris Descartes, Université Paris Descartes, Centre hospitalier Sainte Anne, Paris F-75014, France. i.amado@ch-sainte-anne.fr
Bourdel
M C
MC
Daban
C
C
Poirier
M F
MF
Loo
H
H
Bouhours
P
P
Krebs
M O
MO
D000328:Adult; D000704:Analysis of Variance; D014150:Antipsychotic Agents / Q000494:pharmacology / Q000627:therapeutic use*; D001288:Attention / Q000187:drug effects; D001289:Attention Deficit Disorder with Hyperactivity / Q000188:drug therapy* / Q000209:etiology; D002755:Choice Behavior / Q000187:drug effects; D003463:Cues; D005133:Eye Movements / Q000187:drug effects; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D009483:Neuropsychological Tests; D010775:Photic Stimulation / Q000379:methods; D011446:Prospective Studies; D011569:Psychiatric Status Rating Scales; D011930:Reaction Time / Q000187:drug effects; D018967:Risperidone / Q000494:pharmacology / Q000627:therapeutic use*; D012559:Schizophrenia / Q000150:complications / Q000188:drug therapy; D012562:Schizophrenia, Disorganized / Q000188:drug therapy*; D012565:Schizophrenic Psychology; D055815:Young Adult
D014150:Antipsychotic Agents; D018967:Risperidone