Smooth pursuit and saccadic abnormalities in first-episode schizophrenia.
BACKGROUND
Previous studies of oculomotor dysfunction in schizophrenia have tended to concentrate on abnormalities of smooth pursuit eye tracking in chronic medicated patients. We report the results of a study of smooth pursuit, reflexive and antisaccade performance in drug naive and antipsychotic treated first-episode schizophrenic patients.


METHODS
Smooth pursuit and saccadic eye movements were recorded in 36 first-episode schizophrenic patients and 36 controls matched for age and estimated IQ. The schizophrenic patients were divided into drug-naive (N = 17) and antipsychotic treated groups (N = 19).


RESULTS
Smooth pursuit velocity gain was significantly lower than controls only in the drug-naive patients. The treated patients did not differ significantly from either the controls or the untreated group. In an antisaccade paradigm both treated and drug-naive schizophrenic patients demonstrated an increased number of errors, but only drug-naive patients also demonstrated an increased latency in initiating correct antisaccades.


CONCLUSIONS
These impairments are unlikely to be due to a generalized deficit in oculomotor function in the schizophrenic groups, as there were no differences between the groups in saccadic metrics on a reflexive saccade task. The results show that both smooth pursuit and saccadic abnormalities are present at the onset of schizophrenia and are integral to the disorder.
Hutton
S B
SB
Department of Neuroscience and Psychological Medicine, Imperial College School of Medicine, Charing Cross Hospital, Royal Postgraduate Medical School, London.
Crawford
T J
TJ
Puri
B K
BK
Duncan
L J
LJ
Chapman
M
M
Kennard
C
C
Barnes
T R
TR
Joyce
E M
EM
D000293:Adolescent; D000328:Adult; D014150:Antipsychotic Agents / Q000627:therapeutic use; D002908:Chronic Disease; D005260:Female; D006801:Humans; D008297:Male; D009802:Oculomotor Nerve / Q000187:drug effects / Q000503:physiopathology; D011569:Psychiatric Status Rating Scales; D011698:Pursuit, Smooth / Q000187:drug effects / Q000502:physiology*; D011930:Reaction Time / Q000187:drug effects / Q000502:physiology; D012018:Reflex / Q000187:drug effects / Q000502:physiology; D012438:Saccades / Q000187:drug effects / Q000502:physiology*; D012559:Schizophrenia / Q000175:diagnosis / Q000188:drug therapy / Q000503:physiopathology*; D012565:Schizophrenic Psychology
D014150:Antipsychotic Agents