Goltseker Koral, Yankelevitch-Yahav Roni, Albelda Noa S, Joel Daphna
School of Psychological Sciences, Tel-Aviv University.
School of Psychological Sciences, Tel-Aviv University; Sagol School of Neuroscience, Tel-Aviv University;
J Vis Exp. 2015 Jan 9(95):52287. doi: 10.3791/52287.
In the signal attenuation rat model of obsessive-compulsive disorder (OCD), lever-pressing for food is followed by the presentation of a compound stimulus which serves as a feedback cue. This feedback is later attenuated by repeated presentations of the stimulus without food (without the rat emitting the lever-press response). In the next stage, lever-pressing is assessed under extinction conditions (i.e., no food is delivered). At this stage rats display two types of lever-presses, those that are followed by an attempt to collect a reward, and those that are not. The latter are the measure of compulsive-like behavior in the model. A control procedure in which rats do not experience the attenuation of the feedback cue serves to distinguish between the effects of signal attenuation and of extinction. The signal attenuation model is a highly validated model of OCD and differentiates between compulsive-like behaviors and behaviors that are repetitive but not compulsive. In addition the measures collected during the procedure eliminate alternative explanations for differences between the groups being tested, and are quantitative, unbiased and unaffected by inter-experimenter variability. The major disadvantages of this model are the costly equipment, the fact that it requires some technical know-how and the fact that it is time-consuming compared to other models of OCD (11 days). The model may be used for detecting the anti- or pro-compulsive effects of pharmacological and non-pharmacological manipulations and for studying the neural substrate of compulsive behavior.
在强迫症（OCD）的信号衰减大鼠模型中，大鼠按压杠杆获取食物后会出现一个复合刺激，该刺激作为反馈线索。随后，在无食物（大鼠未发出杠杆按压反应）的情况下重复呈现该刺激，反馈会逐渐减弱。在下一阶段，在消退条件下（即不提供食物）评估杠杆按压情况。在此阶段，大鼠表现出两种类型的杠杆按压，一种是随后试图获取奖励的，另一种则不是。后者是该模型中强迫样行为的指标。一种对照程序是让大鼠不经历反馈线索的衰减，以此区分信号衰减和消退的影响。信号衰减模型是一种经过高度验证的强迫症模型，能够区分强迫样行为和重复性但非强迫性的行为。此外，在该程序中收集的测量数据排除了对受试组间差异的其他解释，并且是定量的、无偏的，不受实验者间差异的影响。该模型的主要缺点是设备成本高，需要一些技术知识，并且与其他强迫症模型相比耗时较长（11天）。该模型可用于检测药物和非药物操作的抗强迫或促强迫作用，以及研究强迫行为的神经基础。
