Terman M, Kling J W
J Exp Anal Behav. 1968 Jan;11(1):29-37. doi: 10.1901/jeab.1968.11-29.
Rats were trained to respond to the brighter of two keys. Four animals were trained with food pellets and four with electrical brain stimulation. Each discrimination sequence was initiated when the animal broke a light beam at the rear of the chamber, turning on the key lights and starting a 30-sec reinforcement period. An initial response on the brighter key was immediately reinforced, and further responses on the brighter key were then intermittently reinforced. Any time the dimmer key was pressed, a 30-sec timeout was introduced. During timeout, no response had any programmed consequence. When the reinforcement period or the timeout ended, a new discrimination sequence could be initiated. Daily 1-hr training sessions were conducted, and after seven or eight sessions, all animals were at or near errorless performance levels. The luminance of the brighter key was then systematically reduced, in seven steps, with two 30-min test sessions at each step. Orderly psychometric functions were generated for individual animals. Initial acquisition, once position preferences were broken, was equally rapid for food and for brain-stimulation animals, and the two reinforcement procedures yielded comparable levels of brightness discriminability.
训练大鼠对两个按键中较亮的那个做出反应。四只动物通过食物颗粒进行训练，另外四只通过脑电刺激进行训练。当动物打破实验箱后部的光束时，每个辨别序列开始，此时按键灯亮起并开始30秒的强化期。对较亮按键的首次反应会立即得到强化，随后对较亮按键的进一步反应会间歇性地得到强化。每当按下较暗的按键时，就会引入30秒的超时。在超时期间，任何反应都没有预设的结果。当强化期或超时结束时，可以启动新的辨别序列。每天进行1小时的训练，经过七到八次训练后，所有动物都达到或接近无误的表现水平。然后，较亮按键的亮度被系统地分七个步骤降低，每个步骤进行两个30分钟的测试。为每只动物生成了有序的心理测量函数。一旦位置偏好被打破，食物奖励组和脑刺激奖励组的初始习得速度相同，并且两种强化程序产生的亮度辨别能力水平相当。
