Simulation of motion on the skin. IV. Responses of Pacinian corpuscle afferents innervating the primate hand to stripe patterns on the OPTACON.
Simulation of motion on the skin. IV. Responses of Pacinian corpuscle afferents innervating the primate hand to stripe patterns on the OPTACON.
复制标题
DOI：
10.1152/jn.1990.64.1.236
复制
发表时间：
1990-07
影响因子：
2.5
通讯作者：
C. Palmer;E. P. Gardner
中科院分区：
文献类型：
--
作者：
C. Palmer;E. P. Gardner
1.为了测量猕猴正中神经和尺神经中Pacinian小体（PC）传入的空间敏锐度，我们在计算机控制的OPTACON刺激器上显示间隔1-13 mm的水平条图案。通过以100、50和25 Hz的速率同时脉冲成对的行来测量两点分辨率;每对以1.2 mm的步长在皮肤上串联移动，以30-120 mm/s的速度模拟切向运动。单纤维反应的报告，从八个生理上确定的PC传入神经支配的手指和手掌在麻醉猴。2. Pacinian传入不同的敏感性条纹模式移动的手。当其中一个条接近场中心时，爆发式PC发射两个或三个尖峰/脉冲的爆发，当相邻的条横跨中心时，发射一个尖峰/脉冲的爆发。这些突发的结果，在双峰响应曲线的条纹间距大于或等于2.4毫米。因此，在现场中心的个别条纹的通道表示的脉冲叠加在一个连续的尖峰序列的突发。不幸的是，这些纤维中的许多也表现出与条纹图案无关的放电波动，因此模糊了其清晰的表现。3.其余的PC人口显示均匀的敏感性反应，类似于以前报道的快速适应（RA）传入。只要至少有一个条包含在场内，它们就会发射一个尖峰/脉冲。它们合并了间隔小于一个视野直径的单个条纹，并在更宽的间隔处显示出发射暂停。因此，条纹图案中的间隙的空间分辨率由接收场直径决定，当使用OPTACON进行测试时，接收场直径延伸至9.6 mm。4. PC显示较差的空间分辨率比RA，因为它们更大的感受野和不规则的放电模式。8个PC中只有2个表现出活动暂停，代表间隔4.8 mm的条之间的差距，而14个RA中有11个在条之间短暂停止放电。仅在条间距为1 cm（8行）或更大时观察到所有受试PC的单个条带分辨率。条纹的空间分辨率进一步阻碍PC传入的趋势，以summate输入间隔小于2.4毫米的条纹，这导致在响应曲线与一个单一的，大幅度的宽峰。（400字处截断摘要）
1. To measure spatial acuity of Pacinian corpuscle (PC) afferents in the median and ulnar nerves of macaque monkeys, we displayed horizontal bar patterns spaced 1-13 mm apart on a computer-controlled OPTACON stimulator contacting the hand. Two-point resolution was measured by simultaneously pulsing pairs of rows at rates of 100, 50, and 25 Hz; each pair was shifted in tandem across the skin in 1.2-mm steps to simulate tangential motion at speeds of 30-120 mm/s. Single-fiber responses are reported from eight physiologically identified PC afferents innervating the fingers and palm in anesthetized monkeys. 2. Pacinian afferents differ in their sensitivity to stripe patterns moved across the hand. Bursting PCs fire bursts of two or three spikes/pulse when one of the bars is close to the field center and one spike/pulse when adjacent bars straddle the center. These bursts result in double-peaked response profiles at stripe spacings greater than or equal to 2.4 mm. The passage of individual stripes over the field center is therefore represented by bursts of impulses superimposed on a continuous spike train. Unfortunately, many of these fibers also demonstrate fluctuations in firing that appear unrelated to the stripe pattern and therefore obscure its clear representation. 3. The remainder of the PC population displays uniform-sensitivity responses that resemble those previously reported for rapidly adapting (RA) afferents. They fire one spike/pulse as long as at least one of the bars is contained within the field. They merge individual stripes spaced less than one field diameter apart and show a pause in firing at wider spacing. Spatial resolution of gaps in the stripe pattern is therefore determined by receptive-field diameters, which extend up to 9.6 mm when tested with the OPTACON. 4. PCs display poorer spatial resolution than RAs, because of their larger receptive fields and less regular firing patterns. Only two of eight PCs tested demonstrated a pause in activity representing the gap between bars spaced 4.8 mm apart, whereas 11 of 14 RAs ceased firing briefly between stripes. Resolution of the individual stripes by all of the PCs tested was observed only at bar spacings of 1 cm (8 rows) or more. Spatial resolution of stripes is further impeded by the tendency of PC afferents to summate inputs from stripes spaced less than 2.4 mm apart; this results in response profiles with a single, large-amplitude broad peak.(ABSTRACT TRUNCATED AT 400 WORDS)