Related Experiment Videos
Hypometric primary saccades of schizophrenics in a delayed-response task
S Everling1, P Krappmann, S Preuss
1Brain Research Institute, University of Bremen, Germany. i10o@zfn.uni-bremen.de
Experimental Brain Research
|September 1, 1996
Summary
Schizophrenic patients exhibit saccade deficits, particularly hypometric saccades in memory-guided tasks. This suggests impaired primary saccade programming, potentially due to reduced prefrontal inhibition.
Area of Science:
- Neuroscience
- Psychiatry
- Ophthalmology
Background:
- Schizophrenia is a complex psychiatric disorder associated with various cognitive deficits.
- Ocular motor control, specifically saccade execution, has been implicated as a potential biomarker for schizophrenia.
Purpose of the Study:
- To investigate the execution of delayed and memory-guided saccades in individuals with schizophrenia compared to healthy controls.
- To explore potential deficits in the programming of primary saccades in schizophrenia.
Main Methods:
- A delayed-saccade task and a memory-guided saccade task were administered to 15 schizophrenic patients and 15 normal subjects.
- Saccade parameters, including amplitude and final eye position, were analyzed.
Main Results:
- Schizophrenic subjects demonstrated significantly hypometric saccades in the memory-guided saccade task.
- Incorrect delayed saccades were also hypometric in schizophrenics, unlike in controls.
- No differences were found in the final eye position after correction saccades between groups.
Conclusions:
- Schizophrenic patients show a deficit in programming primary saccades when targets are either visually presented or memorized.
- Results support an averaging effect hypothesis for saccade generation and suggest a role for prefrontal cortex dysfunction.