Lee K H, Williams L M, Haig A, Goldberg E, Gordon E
The Brain Dynamics Centre, Westmead Hospital, NSW 2145, Westmead, Australia.
Clin Neurophysiol. 2001 Aug;112(8):1499-507. doi: 10.1016/s1388-2457(01)00584-3.
Frontal and lateralized schizophrenia disturbances were examined in terms of arousal-modulated changes in 40 Hz Gamma activity.
Forty patients with schizophrenia and 40 age- and gender-matched controls were studied in a conventional auditory ERP oddball paradigm. We investigated sub-averaged Gamma activity based upon a simultaneous measure of electrodemal skin conductance response (phasic arousal) to differentiate novelty (large responses) from routinization (small or no responses). Both early Gamma (Gamma 1) and later induced Gamma (Gamma 2) activities were examined.
Patients with schizophrenia (compared with controls) had significantly reduced Gamma 1 amplitude in the right hemisphere for novelty processing and delayed Gamma 2 latency in the left hemisphere for both novelty and routinization. Overall, reduced Gamma 1 amplitude in patients with schizophrenia was also evident.
These findings indicate that the normal laterality of Gamma activity is specifically disturbed in schizophrenia in response to novel, but not routine (familiar) stimuli. The distinct pattern of findings suggests a dysregulation of activation across left and right hemispheres during initial attention and preparatory phases of information processing, in particular, in patients with schizophrenia.
根据40赫兹伽马活动中与觉醒调节相关的变化，对额叶和偏侧化精神分裂症障碍进行研究。
采用传统听觉事件相关电位（ERP）oddball范式，对40例精神分裂症患者及40名年龄和性别匹配的对照者进行研究。我们基于对皮肤电传导反应（相位觉醒）的同步测量来研究平均伽马活动，以区分新奇性（反应大）和常规化（反应小或无反应）。对早期伽马（伽马1）和后期诱发伽马（伽马2）活动均进行了检测。
精神分裂症患者（与对照者相比）在处理新奇性刺激时，右半球伽马1波幅显著降低；在处理新奇性和常规化刺激时，左半球伽马2潜伏期延迟。总体而言，精神分裂症患者伽马1波幅降低也很明显。
这些发现表明，精神分裂症患者在对新奇而非常规（熟悉）刺激的反应中，伽马活动的正常偏侧性受到了特异性干扰。这一独特的发现模式表明，在信息处理的初始注意和准备阶段，尤其是精神分裂症患者，左右半球的激活存在失调。
