Nordholm A F, Lavond D G, Thompson R F
Neurosciences Program, University of Southern California, Los Angeles 90089-2520.
Behav Brain Res. 1991 Jul 1;44(1):27-34. doi: 10.1016/s0166-4328(05)80236-0.
Bloedel and associates recently claimed to have established conditioned eyeblink responses in the acute decerebrate, decerebellate rabbit. Their training procedure was extreme massed practice (mean intertrial interval of 9 s) and they used an idiosyncratic definition of the conditioned response (10% or more of the unconditioned response amplitude). They did not measure or control the excitability of their preparations and did not run any separate control groups for alpha responses, alpha conditioning or pseudoconditioning. Using normal animals we compared their training procedure with procedures standard in the field and analyzed the consequences of their scoring procedure. Our group trained at a 30-s intertrial interval (ITI) showed clear learning in the training session. In marked contrast, 3 groups trained at a 9-s ITI developed no conditioned responses. We also found that the method of scoring used by Bloedel and associates counts many spontaneous responses as conditioned responses (CRs) if unconditioned response (UR) amplitudes are low, excludes genuine CRs if UR amplitudes are high and does not control for the occurrence of spontaneous responses. It must therefore be concluded that the eyeblink responses to tone reported by Bloedel and associates to occur in the decerebrate, decerebellate rabbit are not associative CRs as they develop in the normal animal.
布洛德尔及其同事最近声称已在急性去大脑、去小脑的兔子身上建立了条件性眨眼反应。他们的训练程序是极端密集练习（平均试间间隔为9秒），并且他们对条件反应使用了一种特殊的定义（无条件反应幅度的10%或更多）。他们没有测量或控制其制备物的兴奋性，也没有针对α反应、α条件作用或假条件作用设立任何单独的对照组。我们使用正常动物，将他们的训练程序与该领域的标准程序进行了比较，并分析了他们评分程序的结果。我们的小组在30秒试间间隔（ITI）下进行训练，在训练过程中显示出明显的学习效果。形成鲜明对比的是，在9秒ITI下训练的3个小组未产生条件反应。我们还发现，如果无条件反应（UR）幅度较低，布洛德尔及其同事所使用的评分方法会将许多自发反应计为条件反应（CRs）；如果UR幅度较高，则会排除真正的CRs，并且没有对自发反应的发生进行控制。因此，必须得出结论，布洛德尔及其同事报告的在去大脑、去小脑的兔子中出现的对音调的眨眼反应并非正常动物中形成的联想性CRs。
