Desiraju T
Brain Res. 1976 Jun 18;109(3):473-85. doi: 10.1016/0006-8993(76)90028-7.
An investigation of the nature of laminar potentials and impulse discharges of units of dorsolateral prefrontal cortex (FC) evoked by stimulations of cingulate gyrus was made in rhesus monkey. Anterior cingulate stimulations evoked 1.0--1.5 msec latency waves, positive on pial surface and negative at FC depths of about 500--2000 mum with about the same time scale. Following the positive wave there was also a negative wave response. The amplitude and duration of the surface positive wave and negative wave of response varied according to the state of background EEG of the area. During steady EEG the positive wave was well developed and the negative wave was incipient but during EEG oscillations, the positive wave was markedly diminished and the negative wave enlarged. The alteration of responsiveness was also confirmed in depths by changes of reversed polarity potentials corresponding temporally to surface potentials. Discrete responses of FC were evoked at stimulus frequencies of up to 20 Hz. Higher frequencies resulted in depression of responsiveness. Alternate responses were depressed between 20 and 40 Hz and all responses were progressively depressed with still higher frequencies. Impulse discharges of FC units were evoked either singly or in bursts by the cingulate stimulations. Single impulse responses were commonly found. Presumably monosynaptic responses were in the latency range of 1.2-3.0 msec. They were found at depths of about 500 mum and 1000 mum. Long latency (7 msec) responses were also observed in the upper levels of cortex. The latency of the unitary response of a multi-impulse burst was in the range of 6.5-16 msec and the frequency of impulses in burst was in the order of 500-750 Hz. Such burst responses occurred on the declining phase of the depth negative wave evoked by the cingulate stimulation. The anterior cingulate effects were found to be distributed on the prefrontal cortex from arcuate sulcus to two-thirds distance rostrally. The unit responses were more commonly found in laminae between 0.4 and 1.0 mm depth than at other depths. The cingulate effects on FC were not affected by lesion of nucleus medialis dorsalis thalami or by ablation of the pre-motor cortex. The study discloses a basis by which functional states of limbic cortex can powerfully modulate the functioning of prefrontal neocortex of primate.
在恒河猴身上对扣带回刺激诱发的背外侧前额叶皮质（FC）神经元的层流电位和冲动放电的性质进行了研究。前扣带回刺激诱发潜伏期为1.0 - 1.5毫秒的波，在软膜表面为正，在FC深度约500 - 2000微米处为负，时间尺度大致相同。在正波之后还有一个负波反应。反应的表面正波和负波的振幅和持续时间根据该区域背景脑电图的状态而变化。在脑电图稳定期间，正波发育良好，负波刚开始出现，但在脑电图振荡期间，正波明显减弱，负波增大。通过与表面电位在时间上相对应的极性反转电位的变化，也在深度上证实了反应性的改变。在高达20赫兹的刺激频率下诱发了FC的离散反应。更高的频率导致反应性降低。在20至40赫兹之间交替反应受到抑制，频率更高时所有反应逐渐受到抑制。扣带回刺激可单独或成串地诱发FC神经元的冲动放电。常见单个冲动反应。推测单突触反应的潜伏期在1.2 - 3.0毫秒范围内。它们出现在约500微米和1000微米的深度。在皮质上层也观察到长潜伏期（7毫秒）反应。多冲动爆发的单位反应潜伏期在6.5 - 16毫秒范围内，爆发中的冲动频率约为500 - 750赫兹。这种爆发反应出现在扣带回刺激诱发的深度负波的下降阶段。发现前扣带回效应分布在前额叶皮质从弓状沟到喙侧三分之二距离处。单位反应在深度0.4至1.0毫米之间的层中比在其他深度更常见。扣带回对FC的影响不受背内侧丘脑核损伤或运动前皮质切除的影响。该研究揭示了边缘皮质的功能状态能够有力地调节灵长类动物前额叶新皮质功能的基础。
