Kuo Chung-Chih, Chen Jyh-Horng, Tsai Chin-Yen, Liang Keng-Chen, Yen Chen-Tung
Institute of Zoology, National Taiwan University, Taipei.
Chin J Physiol. 2005 Dec 31;48(4):200-9.
Evoked neural activity (ensemble single-unit activity and evoked field potential) and functional magnetic resonance imaging (fMRI) changes of the primary somatosensory cortex in response to electrical stimulation of the hind paw were studied in rats under anesthesia. The effects of stimulation frequency (ranging from 0.3 to 10 Hz) and types of anesthetics (alpha-chloralose and sodium pentobarbital) on blood oxygen level dependent (BOLD) activation and neural activation were compared. Both ensemble single-unit activity and BOLD signal changes achieved maximal activation at 3 Hz of stimulation and responses were significantly stronger under alpha-chloralose anesthesia. The maximal activation of the integral evoked potential (sigmaEP), in contrast, was the highest at 10 Hz; and the values were similar for alpha-chloralose and pentobarbital. These analyses revealed that fMRI image changes were better correlated with ensemble single-unit activity than with sigmaEP during somatosensory stimulations.
在麻醉状态下的大鼠中，研究了初级体感皮层对后爪电刺激的诱发神经活动（群体单单位活动和诱发电场电位）以及功能磁共振成像（fMRI）变化。比较了刺激频率（范围为0.3至10 Hz）和麻醉剂类型（α-氯醛糖和戊巴比妥钠）对血氧水平依赖（BOLD）激活和神经激活的影响。群体单单位活动和BOLD信号变化在3 Hz刺激时均达到最大激活，且在α-氯醛糖麻醉下反应明显更强。相比之下，积分诱发电位（sigmaEP）的最大激活在10 Hz时最高；α-氯醛糖和戊巴比妥钠的值相似。这些分析表明，在体感刺激期间，fMRI图像变化与群体单单位活动的相关性比与sigmaEP的相关性更好。
