Capacities of humans and monkeys to discriminate vibratory stimuli of different frequency and amplitude: a correlation between neural events and psychological measurements.
Capacities of humans and monkeys to discriminate vibratory stimuli of different frequency and amplitude: a correlation between neural events and psychological measurements.
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人类和猴子区分不同频率和幅度的振动刺激的能力：神经事件和心理测量之间的相关性。
DOI：
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发表时间：
1975
影响因子：
2.5
通讯作者：
V. Mountcastle
中科院分区：
文献类型：
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作者：
R. LaMotte;V. Mountcastle
猴子和人类区分振幅或频率不同的机械正弦波的能力是在一个两种选择的强迫选择任务中测量的。相对于检测阈值，在17-30 dB范围内，两种物种的振幅识别差值保持在标准振幅的10%附近。相对于检测阈值，在20和29 dB处确定了20-40 Hz范围内的等主观强度曲线。这些曲线遵循阈值曲线，并且在两个物种中是相同的。人类和猴子的频率分辨差异阈值分别为1.8 Hz和2.7 Hz；这两个物种的值范围几乎完全重叠。我们相信，这些差异的小尺寸表明，任何一个物种的受过高度训练的个体都有能力确定躯体刺激和由它们引起的神经事件在时间顺序上的微小差异。在一系列的实验中，我们证明了两种受试者对颤振的两个不同方面都有两个阈值，这两个方面沿着密集连续体相互位移。对于这两种物种，阈值频率识别所需的最小刺激幅度比足以检测的最小刺激幅度高约8db。这种振幅的差异被称为无调性音程，并与快速适应的机械感受器传入（迈斯纳传入）的绝对阈值和调谐阈值相匹配，这种传入神经支配着猴子的无毛皮肤。这些和先前的研究结果表明，在颤振感方面，行为和神经事件之间存在许多直接关联。颤振强度和频率的神经编码似乎是不同的。检测机械正弦波存在的能力和判断其主观强度的能力很可能取决于迈斯纳传入事件总数中的活动标准水平，前者取决于这些纤维中最敏感的小群体中任何活动的外观（绝对阈值），后者取决于每个振幅水平上神经元元素活动群体的总体大小。由振幅增加的正弦波引起的相关神经群的总活动定义了一个假体连续体，受试者可以沿着这个连续体判断感觉的大小。
The capacities of monkeys and humans to discriminate between mechanical sinusoids differing in amplitude or frequency were measured in a two-alternative, forced-choice task. The difference limen for amplitude discrimination for both species remained constant near 10% of the standard amplitude over the range of 17-30 dB, relative to detection threshold. Equal subjective intensity curves in the 20-40 Hz range were determined at 20 and 29 dB, relative to detection threshold. These curves followed the threshold curve and were identical for the two species. The difference limen for frequency discrimination averaged 1.8 Hz for humans and 2.7 Hz for monkeys; the range of values for the two species overlapped nearly completely. The small sizes of these difference limens indicate, we believe, the capacity of highly trained individuals of either species to ascertain small differences in the temporal order of somesthetic stimuli and of the neural events evoked by them. In one series of experiments we demonstrated that subjects of both species possess two threshold for two different aspects of flutter-vibration which are displaced from each other along the intensive continuum. For either species, the minimum level of stimulus amplitude required for threshold frequency discrimination is about 8 dB above that sufficient for detection. This difference in amplitude is called the atonal interval and matches that observed between absolute and tuning thresholds for quickly adapting, mechanoreceptor afferents (the Meissner afferents) which innervate the glabrous skin of the monkey hand. These and previous findings have permitted a number of direct correlations between behavioral and neural events as regards the sense of flutter. The neural codes for the intensity and frequency of flutter appear to be different. The capacity to detect the presence of a mechanical sinusoid and the capacity to judge its subjective intensity are likely to depend on criterion levels of activity in the total population of Meissner afferents, the former on the appearance of any activity (absolute threshold) in a small population of the most sensitive of these fibers and the latter on the overall size of the active population of neuronal elements at each level of amplitude. The total activity in the relevant neural population elicited by sinusoids of increasing amplitude defines a prothetic continuum along which subjects can judge the magnitude of sensation..