Chamberlain Ann C, Viventi Jonathan, Blanco Justin A, Kim Dae-Hyeong, Rogers John A, Litt Brian
Department of Bioengineering, University of Pennsylvania, Philadelphia, PA 19104, USA.
Annu Int Conf IEEE Eng Med Biol Soc. 2011;2011:761-4. doi: 10.1109/IEMBS.2011.6090174.
Advances in neural electrode technology are enabling brain recordings with increasingly fine spatial and temporal resolution. We explore spatio-temporal (ST) patterns of local field potential spikes using a new high-density active electrode array with 500 μm resolution. We record subdural micro-electrocorticographic (μECoG) signals in vivo from a feline model of acute neocortical epileptiform spikes and seizures induced with local administration of the GABA antagonist, picrotoxin. We employ a clustering algorithm to separate 2-dimensional (2-D) spike patterns to isolate distinct classes of spikes unique to the interictal and ictal states. Our findings indicate that the 2-D patterns can be used to distinguish seizures from non-seizure state. We find two statistically significant ST patterns that uniquely characterize ictal epochs. We conclude that millimeter-scale ST spike dynamics contain useful information about ictal state. This finding may be important to understanding mechanisms underlying local circuit activity during seizure generation. Further work will investigate whether patterns we identify can increase our understanding of seizure dynamics and their underlying mechanisms and inform new electrical stimulation protocols for seizure termination.
神经电极技术的进步使得能够以越来越高的空间和时间分辨率进行脑记录。我们使用一种具有500微米分辨率的新型高密度有源电极阵列，探索局部场电位尖峰的时空（ST）模式。我们在体内记录了由局部施用GABA拮抗剂印防己毒素诱导的急性新皮质癫痫样尖峰和癫痫发作的猫模型的硬膜下微脑电图（μECoG）信号。我们采用聚类算法来分离二维（2-D）尖峰模式，以分离出发作间期和发作期特有的不同类别的尖峰。我们的研究结果表明，二维模式可用于区分癫痫发作和非癫痫发作状态。我们发现了两种具有统计学意义的ST模式，它们独特地表征了发作期。我们得出结论，毫米级的ST尖峰动力学包含有关发作期状态的有用信息。这一发现对于理解癫痫发作产生过程中局部电路活动的潜在机制可能很重要。进一步的工作将研究我们识别出的模式是否能增进我们对癫痫发作动力学及其潜在机制的理解，并为癫痫终止的新电刺激方案提供信息。
