Reuter Benedikt, Jäger Markus, Bottlender Ronald, Kathmann Norbert
Humboldt-Universiät zu Berlin, Berlin, Germany.
Neuropsychologia. 2007 Apr 9;45(8):1840-8. doi: 10.1016/j.neuropsychologia.2006.12.006. Epub 2007 Jan 26.
Schizophrenia patients show prefrontal cortex dysfunctions of neurodevelopmental origin, but the cognitive implications of these dysfunctions are not yet understood. This study used experimental variations of oculomotor tasks to evaluate the relative roles of volitional action initiation and the inhibition of reflexive behavior. Thirty schizophrenia patients and 30 control participants performed standard prosaccades (SP), standard antisaccades (SA), delayed prosaccades (DP), and delayed antisaccades (DA). The delayed tasks allowed separating the inhibition of erroneous prosaccades and the initiation of volitional saccades, which coincide in the SA task. Arrow-cued (AC) saccades were used to evaluate initiation without any inhibitory component. Erroneous prosaccades were less frequent in the delayed tasks than in the SA task. Error rates were generally larger in schizophrenia patients than in control participants, but the deficit was smaller in the delayed tasks than in the SA task. Correct saccade latencies of schizophrenia patients were normal in the SP task, but not on conditions of volitional saccade initiation (all other tasks). Volitional saccade latencies were positively correlated with error rates in the schizophrenia group. These results confirm that schizophrenia patients have a specific deficit in initiating volitional action, which may also contribute to the increased error rates.
精神分裂症患者表现出神经发育起源的前额叶皮质功能障碍，但这些功能障碍对认知的影响尚不清楚。本研究采用眼动任务的实验变体来评估意志行动启动和反射行为抑制的相对作用。30名精神分裂症患者和30名对照参与者进行了标准的前扫视（SP）、标准的反扫视（SA）、延迟前扫视（DP）和延迟反扫视（DA）。延迟任务允许区分对错误前扫视的抑制和意志性扫视的启动，这在SA任务中是同时发生的。箭头提示（AC）扫视用于评估没有任何抑制成分的启动。在延迟任务中，错误前扫视比在SA任务中更不频繁。精神分裂症患者的错误率一般比对照参与者更高，但在延迟任务中的缺陷比在SA任务中小。精神分裂症患者在SP任务中的正确扫视潜伏期正常，但在意志性扫视启动的条件下（所有其他任务）则不正常。在精神分裂症组中，意志性扫视潜伏期与错误率呈正相关。这些结果证实，精神分裂症患者在启动意志行动方面存在特定缺陷，这也可能导致错误率增加。
