Lloyd M A, Appel J B, McGowan W T
Psychopharmacology (Berl). 1978 Jul 19;58(3):241-6. doi: 10.1007/BF00427386.
A discrete-trial, two-choice, 'yes-no' procedure was used to determine the extent to which the perceptual effects of compounds such as morphine and chlorpromazine (CPZ) can be attributed to drug-induced changes in ability to detect shock stimuli (sensitivity). Both morphine (4.0, 5.0, and 6.0 mg/kg) and CPZ (0.25, 0.50, and 1.0 mg/kg) significantly reduced accuracy and increased the times (i.e., lowered the speeds) to initiate trials and to make choice responses. The effects of morphine appeared to be somewhat greater than those of CPZ, particularly at the lowest shock intensity (0.05 mA). When compared to appropriate saline control days, morphine, but not CPZ, significantly reduced accuracy of discrimination on trials when shocks were presented, whereas CPZ, but not morphine, reduced accuracy on no-shock trials. The effects of morphine, but not of CPZ, on accuracy (both overall and on shock trials) decreased as shock intensity increased. The effects of shock intensity were generally inversely related to the effects of morphine and directly related to the effects of CPZ.
采用离散试验、二选一、“是-否”程序来确定吗啡和氯丙嗪（CPZ）等化合物的知觉效应在多大程度上可归因于药物引起的检测电击刺激能力（敏感性）的变化。吗啡（4.0、5.0和6.0毫克/千克）和CPZ（0.25、0.50和1.0毫克/千克）均显著降低了准确性，并增加了开始试验和做出选择反应的时间（即降低了速度）。吗啡的效应似乎比CPZ的效应略大，尤其是在最低电击强度（0.05毫安）时。与适当的生理盐水对照日相比，吗啡而非CPZ在呈现电击的试验中显著降低了辨别准确性，而CPZ而非吗啡在无电击试验中降低了准确性。随着电击强度增加，吗啡对准确性的影响（总体和电击试验中）降低，而CPZ则不然。电击强度的效应通常与吗啡的效应呈负相关，与CPZ的效应呈正相关。
