Weisser R, Weisbrod M, Roehrig M, Rupp A, Schroeder J, Scherg M
Section of Biomagnetism, Neurology Department, University of Heidelberg, Voss-Str. 4, 69115 Heidelberg, Germany.
Neuroreport. 2001 Oct 29;12(15):3303-7. doi: 10.1097/00001756-200110290-00031.
This study examined the functional substrate of P50 suppression. Auditory evoked potentials (AEPs) and magnetic fields (AEFs) were recorded from healthy subjects simultaneously and analyzed using spatio-temporal source analysis. The resulting equivalent dipole model for the AEP consisted of one source in the auditory cortex (AC) of each hemisphere and an radially oriented medial frontal source, both with maximum AEP activity around 50 ms. The frontal source was functionally separated from the AC sources since it peaked significantly later and showed significantly larger P50 amplitude suppression. P30m showed neither suppression nor substantial frontal activity. In sum, this study relates P50 suppression to reduction of AC source activity and is the first to yield direct evidence for frontal involvement in P50 suppression.
本研究检测了P50抑制的功能底物。同时记录了健康受试者的听觉诱发电位（AEP）和磁场（AEF），并使用时空源分析进行分析。AEP的等效偶极子模型由每个半球听觉皮层（AC）中的一个源和一个径向定向的内侧额叶源组成，两者在50毫秒左右均具有最大的AEP活动。额叶源在功能上与AC源分离，因为它达到峰值的时间明显更晚，并且显示出明显更大的P50振幅抑制。P30m既没有抑制也没有明显的额叶活动。总之，本研究将P50抑制与AC源活动的减少联系起来，并且首次提供了额叶参与P50抑制的直接证据。
