Short-term adaptation of electrically induced saccades in monkey superior colliculus.
Short-term adaptation of electrically induced saccades in monkey superior colliculus.
复制标题
猴上丘电诱导眼跳的短期适应。
DOI：
10.1152/jn.1996.76.3.1744
复制
发表时间：
1996
影响因子：
2.5
通讯作者：
J. V. Gisbergen
中科院分区：
文献类型：
--
作者：
Bart Melis;J. V. Gisbergen
1. 本研究主要探讨猕猴跳眼运动短期适应的神经机制。在完全黑暗条件下，电刺激（<或= 50微a）在两只猴子的上丘（SC）深层的30个不同部位引发了不同幅度和方向的非随意扫视（e -扫视）。在给定地点的电子扫视可以通过在其发生后立即在距离预期终点一小段距离处呈现视觉目标来适应。在许多连续的试验中，训练猴子通过对视觉目标进行适当的纠正扫视来消除随之而来的错误信号（E-adap范式）。通过适当调整目视目标相对于e -扫视终点的位置，后者可以在振幅和方向上进行修改。2. e -扫视的变化是非常显著的，总是在预期的方向上，并且只有在产生扫视后视觉误差信号时才会发生。这些变化是可塑的，需要随后的E-adap系列与相反的错误信号来取消它们。它们在适应和再适应期间的时间过程表明，这种修饰是一个缓慢而渐进的过程，这与早先在经典视觉适应实验中观察到的结果一致。3. 后适应测试评估了e型眼跳在正常视导眼跳（v型眼跳）中是否也有明显的适应性，结果显示，在大多数情况下，不完全的适应转移是显著的。在E-adap范式的扩展版本中，在目标选择的基础上进行运动规划是可能的，得到了类似的结果，在所有情况下都很重要。在这种情况下，在e -扫视的预期终点出现了一个眼动前视觉目标，这是在猴子自己进行自愿扫视（VE-adap）之前引起的。4. 在另一组实验中，将v -扫视与所研究的特定collle部位的最优扫视向量匹配，并采用经典的asaccadic内目标移位范式（V-adap）进行调整。与先前的发现一致，这种v型适应没有转移到e型扫视。即使在目标选择的基础上进行运动规划的试验中（ve检验），也能得到这一结果。5. 我们的实验表明，眼动起源可以适应，眼动前的目标选择对这一过程并不重要。这两个结果都很好地符合现有的模型，该模型具有访问SC输入的下游自适应校正器。然而，这一理论并不能解释为什么使用三种适应范式（e -顺应、ev -顺应或V-顺应）中的任何一种所达到的跳速适应程度在V-跳速和e -跳速中从未得到相同的表达。讨论了通过在自适应校正器中添加来自额叶视野的皮质输入来扩展模型的论点。
1. This study focuses on the neural mechanisms underlying short-term adaptation of saccadic eye movements in the rhesus monkey. Involuntary saccades of various amplitudes and directions (E-saccades) were elicited in complete darkness by electrical stimulation (< or = 50 microA) in the deeper layers of the superior colliculus (SC) at 30 different sites in two monkeys. E-saccades at a given site could be adapted by presenting a visual target at a small distance from the expected end point immediately after their occurrence. The monkeys were trained to null the ensuing error signal by making the appropriate correction saccade to the visual target in many successive trials (E-adap paradigm). By properly adjusting the location of the visual target relative to the end point of the E-saccade, the latter could be modified in amplitude as well as in direction. 2. E-saccade modifications were highly significant, always in the intended direction, and occurred only if a postsaccadic visual error signal was created. These changes were plastic and required a subsequent E-adap series with an opposite error signal to cancel them. Their time course, both during the adaptation and the readaptation period, indicated that the modification was a slow and gradual process, as has been observed earlier in classical visual adaptation experiments. 3. Postadaptation tests, assessing whether the adaptation of E-saccades was also noticeable in normal visually guided saccades (V-saccades), showed incomplete adaptation transfer that was significant in most cases. A similar result, significant in all cases, was obtained with an extended version of the E-adap paradigm in which movement planning on the basis of target selection was possible. In this case, a presaccadic visual target was presented at the expected end point of the E-saccade, which was evoked just before the monkey would make a voluntary saccade itself (VE-adap). 4. In another series of experiments, V-saccades, which were matched to the optimal saccade vector of the particular collicular site under investigation, were adapted with the classical intrasaccadic target shift paradigm (V-adap). In agreement with earlier findings, this V-adaptation showed no transfer to the E-saccades. This result was obtained even in trials in which movement planning on the basis of target selection was possible (VE-test). 5. Our experiments have shown that saccades of collicular origin can be adapted and that presaccadic target selection is not crucial for this process. Both results are nicely in line with an existing model featuring a downstream adaptive corrector with access to SC inputs. This scheme, however, does not explain why the degree of saccadic adaptation, achieved by applying any of the three adaptation paradigms (E-adap, EV-adap, or V-adap), was never equally expressed in V- and E-saccades. Arguments for extending the model by adding a cortical input from the frontal eye fields to the adaptive corrector are discussed.
登录
查看更多内容
影响因子：
13.9
作者：
Sparks,DL;Mays,LE
通讯作者：
Mays,LE
影响因子：
2.5
作者：
SCHILLER, PH;TRUE, SD;CONWAY, JL
通讯作者：
CONWAY, JL
人类和猴子扫视幅度的快速适应。
影响因子：
4.4
作者：
Albano,JE;King,WM
通讯作者：
King,WM
影响因子：
2.5
作者：
OPTICAN, LM;ROBINSON, DA
通讯作者：
ROBINSON, DA
影响因子：
2.5
作者：
SEGRAVES, MA
通讯作者：
SEGRAVES, MA