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Parkinson*s disease (PD) is degenerative neurological
disorder characterized by tremor,rigidity and bradykinesia.In
addition to somatomotor symptoms , there are also
abnormalities in saccadic eye movements. In the influenceof
research has show much interest in studying disorders of the
basal ganglia in eye movements, particularly saccadic eye
movements.Saccade eye movement enables us torapidly change our
line of sight. There are three types ofsaccades: volitional,
reflexive and Spontaneous. Volitionalsaccades are internally
triggered with a goal. Reflexive saccades are externally
triggered by a sudden appearance of a visual target on the
peripheral retina. Spontaneous saccades are internally
triggered, but without a goal. The basal ganglia appear to
facilitate the initiation ofvoluntary saccades and prevent
reflexive saccades to stimuli. The antisaccade paradigm can
be used to test simultaneously the generation of volitional
saccades andthe suppression of reflex ones. The subjects
were in-structed to look at a point in screen which was at
thesame distance from fixation as the target light,but
inexactly the opposite direction. When the subject
makessaccades toward the target, these inappropriate
saccadesare judged as errors. The previous studies of
antisaccades in PD showed some inconsistent results. Some
reported no difference betweenthe patients and the controls.
However, others reportedthat the latencies and the error
rates were significantincreased in PD patients. In this study,
antisaccade wasstudied in ten patients with mild to moderate
Parkinson'sdisease and ten age-matched normal controls.
Antisaccadewas indistinguishable in latency,error rate, peak
velocity.At the same time, we used skewness as an assessment
ofParkinson's disease.This study shows the PD's patients
hasprolonged latency, higher error rate and higher skewness.
This finding implies that antisaccades are mediated
throughpathways which are affected by Parkinson's disease.
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