Wilson C L, Isokawa M, Babb T L, Crandall P H
Department of Neurology, Reed Neurological Research Center, University of California, Los Angeles 90024.
Exp Brain Res. 1990;82(2):279-92. doi: 10.1007/BF00231248.
Connections in the human mesial temporal lobe were investigated using brief, single pulses of electrical stimulation to evoke field potential responses in limbic structures of 74 epileptic patients. Eight specific areas within these structures were stereotactically targeted for study, including amygdala, entorhinal cortex, presubiculum, the anterior, middle and posterior levels of hippocampus and the middle and posterior levels of parahippocampal gyrus. These sites were studied systematically in order to quantitatively assess the response characteristics and reliability of responses evoked during stimulation of pathways connecting the areas. Specific measures included response probability, amplitude, latency and conduction velocities. The results are assumed to be representative of typical human limbic pathways since all recordings were made interictally and response probabilities across sites were not found to differ significantly between non-epileptogenic vs. identified epileptogenic regions. Field potentials ranging in amplitude from less than 0.1 to greater than 6.0 mV were evoked ipsilaterally, with mean onset latencies and conduction velocities ranging from 4.4 ms and 3.64 m/s in the perforant pathway connecting entorhinal cortex to anterior hippocampus to 24.8 ms and 0.88 m/s in the pathway connecting the amygdala and middle hippocampus. Stimulation of presubiculum and entorhinal cortex were most effective in evoking widespread responses in adjacent limbic recording sites, whereas posterior parahippocampal gyrus appeared functionally separated from other limbic sites since its probability of influencing ipsilateral sites was significantly lower than any other area. It was particularly noteworthy that stimulation did not evoke responses in any sites in contralateral hippocampal formation; even though a large number of sites were tested with bilateral implantation of homotopic electrodes.(ABSTRACT TRUNCATED AT 250 WORDS)
利用短暂的单个电刺激脉冲来诱发74例癫痫患者边缘结构中的场电位反应，对人类内侧颞叶的连接进行了研究。在这些结构内的八个特定区域进行了立体定向靶向研究，包括杏仁核、内嗅皮质、前扣带回、海马的前、中、后水平以及海马旁回的中、后水平。对这些部位进行了系统研究，以定量评估连接这些区域的通路刺激期间诱发反应的特征和可靠性。具体测量指标包括反应概率、幅度、潜伏期和传导速度。由于所有记录均在发作间期进行，且未发现非致痫区与已确定的致痫区之间各部位的反应概率有显著差异，因此这些结果被认为代表了典型的人类边缘通路。同侧诱发的场电位幅度范围从小于0.1mV到大于6.0mV，在连接内嗅皮质与海马前部的穿通通路中，平均起始潜伏期和传导速度分别为4.4ms和3.64m/s，而在连接杏仁核与海马中部的通路中，分别为24.8ms和0.88m/s。刺激前扣带回和内嗅皮质在相邻边缘记录部位诱发广泛反应最为有效，而海马旁回后部似乎在功能上与其他边缘部位分离，因为其影响同侧部位的概率明显低于其他任何区域。特别值得注意的是，刺激在对侧海马结构的任何部位均未诱发反应；尽管使用双侧植入同位电极对大量部位进行了测试。（摘要截短于250字）
