Antisaccade performance in monozygotic twins discordant for schizophrenia: the Maudsley twin study.
OBJECTIVE
Deficiency in antisaccade performance has been proposed as a schizophrenia endophenotype.


METHODS
The authors assessed performance on an antisaccade task (and a prosaccade control condition) by 10 monozygotic twin pairs discordant for DSM-IV schizophrenia and 10 monozygotic healthy twin pairs matched for age, sex, and parental socioeconomic status. The authors computed antisaccade gain, latency, and error rate, as well as prosaccade gain and latency.


RESULTS
The schizophrenic twins made more antisaccade reflexive errors than the nonschizophrenic co-twins and comparison twins, who did not significantly differ from each other. The nonschizophrenic members of discordant pairs performed worse than the comparison twins on antisaccade gain and latency but did not differ from their schizophrenic co-twins on these variables. There were no differences on prosaccade performance. Antisaccade errors were correlated with negative symptoms in the patients.


CONCLUSIONS
Antisaccade spatial accuracy and latency deficits may serve as markers of genetic liability for schizophrenia.
Ettinger
Ulrich
U
Centre for Neuroimaging Sciences, Institute of Psychiatry, King's College London, London SE5 8AF, UK. u.ettinger@iop.kcl.ac.uk
Picchioni
Marco
M
Hall
Mei-Hua
MH
Schulze
Katja
K
Toulopoulou
Timothea
T
Landau
Sabine
S
Crawford
Trevor J
TJ
Murray
Robin M
RM
D000328:Adult; D039721:Diagnostic and Statistical Manual of Mental Disorders; D004200:Diseases in Twins / Q000175:diagnosis* / Q000235:genetics*; D005260:Female; D005819:Genetic Markers; D020022:Genetic Predisposition to Disease; D006801:Humans; D008297:Male; D010290:Parents; D010641:Phenotype; D011569:Psychiatric Status Rating Scales / Q000706:statistics & numerical data; D011597:Psychomotor Performance / Q000502:physiology*; D011930:Reaction Time / Q000235:genetics / Q000502:physiology; D012018:Reflex / Q000235:genetics / Q000502:physiology; D012438:Saccades / Q000235:genetics* / Q000502:physiology*; D012559:Schizophrenia / Q000175:diagnosis* / Q000235:genetics*; D012565:Schizophrenic Psychology; D012923:Social Class; D013647:Task Performance and Analysis; D014430:Twins, Monozygotic
D005819:Genetic Markers