Light Gregory A, Hsu Jung Lung, Hsieh Ming H, Meyer-Gomes Katrin, Sprock Joyce, Swerdlow Neal R, Braff David L
Department of Psychiatry, University of California, San Diego, La Jolla, California 92093-0804, USA.
Biol Psychiatry. 2006 Dec 1;60(11):1231-40. doi: 10.1016/j.biopsych.2006.03.055. Epub 2006 Aug 7.
Gamma band activity has been associated with many sensory and cognitive functions, and is important for cortico-cortical transmission and the integration of information across neural networks. The aims of the present study were to determine if schizophrenia patients have deficits in the generation and maintenance of coherent, synchronized oscillations in response to steady-state stimulation, and to examine the clinical and cognitive correlates of the electroencephalography (EEG) oscillatory dynamics.
Schizophrenia patients (n = 100) and nonpsychiatric subjects (n = 80) underwent auditory steady-state event-related potential testing. Click trains varying in rate of stimulation (20, 30, and 40 Hz) were presented; EEG-evoked power and intertrial phase synchronization were obtained in response to each stimulation frequency. Subjects also underwent clinical and neurocognitive assessments.
Patients had reductions in both evoked power and phase synchronization in response to 30- and 40-Hz stimulation but normal responsivity to 20-Hz stimulation. Maximal deficits were detected in response to 40-Hz stimulation. A modest association of reduced working memory performance and 40-Hz intertrial phase synchronization was present in schizophrenia patients (r = .32, p <.01).
Schizophrenia patients have frequency-specific deficits in the generation and maintenance of coherent gamma-range oscillations, reflecting a fundamental degradation of basic integrated neural network activity.
伽马波段活动与多种感觉和认知功能相关，对皮质-皮质传递及跨神经网络的信息整合很重要。本研究的目的是确定精神分裂症患者在对稳态刺激做出反应时，在产生和维持连贯、同步振荡方面是否存在缺陷，并研究脑电图（EEG）振荡动力学的临床和认知相关性。
精神分裂症患者（n = 100）和非精神科受试者（n = 80）接受听觉稳态事件相关电位测试。呈现刺激频率不同（20、30和40赫兹）的点击序列；针对每个刺激频率获取EEG诱发功率和试验间相位同步。受试者还接受了临床和神经认知评估。
患者对30赫兹和40赫兹刺激的诱发功率和相位同步均降低，但对20赫兹刺激的反应性正常。对40赫兹刺激检测到最大缺陷。精神分裂症患者的工作记忆表现降低与40赫兹试验间相位同步存在适度关联（r = 0.32，p < 0.01）。
精神分裂症患者在产生和维持连贯的伽马波段振荡方面存在频率特异性缺陷，反映了基本整合神经网络活动的根本退化。
