探討以植入式多通道神經探針記錄大鼠視丘誘發神經活動之實用性

Abstract

腦部的神經活動在麻醉狀態和清醒狀態的反應不同，其正常功能必須在清醒狀態下才能表現，若要記錄大鼠在清醒狀態的神經反應，並且避免因動物活動所產生的干擾，可長期植入式的神經探針扮演了相當重要的角色。市面上已有許多為了電生理研究而製作的可植入性神經探針，其中大半是設計用來記錄大腦皮質，缺乏可深達視丘的產品。大鼠視丘腹後側核 (ventral posterior lateral nuclei, VPL) 是體感覺訊號傳遞的中繼站，並且具有體表映射 (somatotopic mapping) 的特性。本研究建立對於大鼠後肢的體表映射圖，並使用NeuroNexus Technologies出產的商用多通道神經探針，長期記錄大鼠視丘腹後側核對於觸覺刺激後肢之反應，評估以此種神經探針應用在大鼠視丘的效果。研究結果顯示：神經元反應隨著植入天數逐漸下降，不同深度神經細胞的活性衰減幅度也有所不同；在植入三個月之後，仍可清楚的記錄到腹後側核對刺激之反應。

The responses of cerebral neural activities are different in anesthetized and awake states, and their real functions can only be evaluated in conscious state. To achieve this goal, implantable neuroprobes play an important role to record the neural activities in conscious state. There are many commercialized implantable neuroprobes and most of them are designed to record the responses of cerebral cortex, and those for recording in thalamus are deficient. The ventral posterior lateral nuclei convey the somatosensory signals and it also has the property of somatotopic organization. This research establishes the map to the hindlimb in the VPL nuclei and evaluates the effect of the multi-channel neuroprobe, produced by NeuroNexus Technologies. The result shows that the responses decay by days, and the extent are different by different depth of VPL. The neuroprobe could record the signals clearly in at least three months.