Abnormalities of inhibitory neuronal mechanisms in the motor cortex of patients with schizophrenia.
Abnormalities of inhibitory neuronal mechanisms in the motor cortex of patients with schizophrenia.
复制标题
精神分裂症患者运动皮层抑制性神经元机制的异常。
DOI：
10.1055/s-2004-815529
复制
发表时间：
2004
影响因子：
4.3
通讯作者：
Meyer Bu
中科院分区：
文献类型：
--
作者：
Malek Bajbouj;Juergen Gallinat;L. Niehaus;Undine E. Lang;S. Roricht;Meyer Bu
背景
使用运动皮层的局灶性经颅磁刺激（TMS）来研究两种皮层激活的抑制性神经元机制，其抑制对侧（兴奋后抑制[PI]）和同侧（经胼胝体抑制[TI]）手部肌肉中正在进行的强直自愿肌电活动。PI遵循皮质脊髓介导的兴奋性运动反应（MEP），并受多巴胺能神经传递的影响。TI反映了对侧运动皮层的经胼胝体介导的抑制，导致刺激同侧肌肉的运动抑制。PI和TI的研究，以探讨是否多巴胺能神经传递或大脑半球间的转移改变精神分裂症。
方法
对16例患者和16例健康对照者进行了TMS检查。在持续的强等长收缩过程中，记录双侧第一背侧骨间肌的表面肌电活动。
结果
当与健康受试者的研究结果相比，精神分裂症患者有一个显着较长的PI和TI。PI的变化支持精神分裂症中枢多巴胺能系统过度活跃的概念。
结论
长时间的TI表明运动皮层之间的半球间连接的异常激活，可能与先前报道的精神分裂症患者胼胝体的病理学有关。
BACKGROUND
Focal transcranial magnetic stimulation (TMS) of the motor cortex was used to study two cortically activated inhibitory neuronal mechanisms that suppress ongoing tonic voluntary electromyographic activity in contralateral (postexcitatory inhibition [PI]) and ipsilateral (transcallosal inhibition [TI]) hand muscles. The PI follows the corticospinally mediated excitatory motor response (MEP) and is influenced by dopaminergic neurotransmission. TI reflects transcallosally mediated inhibition of the contralateral motor cortex, leading to motor inhibition in muscles ipsilateral to stimulation. PI and TI were studied to explore whether dopaminergic neurotransmission or interhemispheric transfers are altered in schizophrenia.
METHODS
TMS was performed in 16 patients with this disease and in 16 healthy control subjects. Surface electromyographic activity was recorded bilaterally from the first dorsal interosseous muscle during a sustained strong isometric contraction.
RESULTS
When compared with the findings in healthy subjects, patients with schizophrenia had a significantly longer PI and TI. The changes of the PI support the notion of an overactivity of the central dopaminergic system in schizophrenia.
CONCLUSION
The prolonged TI suggests an abnormal activation of interhemispheric connections between the motor cortices and may be related to previously reported pathology of the corpus callosum in schizophrenic patients.