Farrell Donald F, Burbank Nicole, Lettich Ettore, Ojemann George A
Department of Neurology, University of Washington School of Medicine, Seattle, WA 98195, USA.
J Clin Neurophysiol. 2007 Jun;24(3):286-93. doi: 10.1097/WNP.0b013e31803bb59a.
Eloquent cortex is generally identified using a variety of techniques including direct electrical stimulation to identify motor-sensory, language, and memory cortex and somatosensory evoked potentials to identify motor-sensory cortex. It is important that these areas of cortex be identified so as to prevent damage during the course of neurosurgical procedures. Seventy epilepsy patients undergoing evaluation for epilepsy surgery with chronically implanted subdural grids were retrospectively studied using both somatosensory evoked potentials and direct electrical stimulation. Direct electrical stimulation of motor-sensory cortex elicited responses over a larger area than did somatosensory evoked potentials. A great deal of individual variation was identified using both techniques. The results presented here support previous conclusions that the concept of homunculus somatotopy (point to point representation) of the motor-sensory cortex be abandoned and that of functional mosaicism of the motor-sensory cortex replace the earlier model. The individual variation found in the human motor-sensory cortex will require a continuation of "brain mapping" to identify eloquent cortex so that these vital areas will be spared during neocortical neurosurgical procedures.
通常使用多种技术来识别明确的皮质，包括直接电刺激以识别运动感觉、语言和记忆皮质，以及体感诱发电位以识别运动感觉皮质。识别这些皮质区域很重要，以便在神经外科手术过程中防止损伤。对70例接受癫痫手术评估且长期植入硬膜下网格的癫痫患者，采用体感诱发电位和直接电刺激进行回顾性研究。与体感诱发电位相比，直接电刺激运动感觉皮质引发反应的区域更大。使用这两种技术均发现了大量个体差异。此处呈现的结果支持先前的结论，即运动感觉皮质的躯体定位同形（点对点表征）概念应被摒弃，运动感觉皮质的功能镶嵌概念应取代早期模型。在人类运动感觉皮质中发现的个体差异将需要继续进行“脑图谱绘制”以识别明确的皮质，从而在新皮质神经外科手术过程中使这些重要区域得以保留。
