Steege T D, Robbins C A, Wyler A R
Brain Res. 1982 Jan 14;231(2):309-24. doi: 10.1016/0006-8993(82)90368-7.
Two rhesus monkeys were trained to control firing patterns of single neurons in parietal cortex (areas 1, 2, 3, 5, 7) using an operant task previously applied to the study of precentral units. Twenty-four of 56 (43%) postcentral cells were controlled in contrast to 71 of 136 (52%) precentral units from these and 4 other rhesus monkeys. In addition, monkeys were able to drive precentral units to more sustained tonic firing rates than they could parietal units. An analysis of interspike interval (ISI) distributions showed that, in contrast to precentral units with modal ISIs of 25-50 ms, 50% of parietal units have modal ISIs of 2 ms. Such short ISIs may account for fewer postcentral units reaching control criteria for this particular operant task. Other factors that may contribute to the reduced control of postcentral cells are discussed, particularly the more complex afferent connections to parietal units when compared to precentral pyramidal tract neurons. The data indirectly support conclusions from previous studies that imply that operant control of cortical units is peripherally mediated and does not primarily involve a 'central' or 'open loop' system.
两只恒河猴接受训练，通过一种先前应用于中央前回神经元研究的操作性任务，来控制顶叶皮质（1、2、3、5、7区）单个神经元的放电模式。在这些以及另外4只恒河猴中，56个中央后回细胞中有24个（43%）被控制，相比之下，136个中央前回神经元中有71个（52%）被控制。此外，与顶叶神经元相比，猴子能够驱使中央前回神经元达到更持续的强直放电率。对峰峰间隔（ISI）分布的分析表明，与模式ISI为25 - 50毫秒的中央前回神经元不同，50%的顶叶神经元模式ISI为2毫秒。如此短的ISI可能是导致较少的中央后回细胞达到该特定操作性任务控制标准的原因。文中还讨论了可能导致中央后回细胞控制减少的其他因素，特别是与中央前回锥体束神经元相比，顶叶神经元的传入连接更为复杂。这些数据间接支持了先前研究的结论，即皮质神经元的操作性控制是由外周介导的，并不主要涉及“中枢”或“开环”系统。
