McCarthy D, Davison M
J Exp Anal Behav. 1979 Nov;32(3):373-86. doi: 10.1901/jeab.1979.32-373.
Five pigeons were trained to detect differences in light intensity. Two stimuli, S1 and S2, differing in intensity, were arranged on the center key of a three-key chamber according to set probabilities. A peck on the center key turned on the two side keys. When S1 was presented on the center key, a peck on the left key was "correct" and when S2 was presented, a peck on the right key was "correct." Correct responses produced reinforcement and incorrect responses produced 3-second blackout. Detection performance was measured under three procedures. The first was a standard signal-detection design in which the probability of S1 was varied and the number of reinforcements obtained for correct responses to S1 was allowed to covary. In the second procedure, the probability of S1 was again varied but the distribution of reinforcements between the two choices was kept equal. In the third procedure, probability of S1 was held constant while the distribution of reinforcements was varied between the two choices. Changes in response bias were a function of variations in the relative reinforcement ratio for the choice responses and not a function of variations in the probability of stimulus presentation. Discriminability remained constant across the three procedures.
训练了五只鸽子来检测光强度的差异。根据设定的概率，将强度不同的两种刺激S1和S2布置在三键实验箱的中央键上。啄一下中央键会打开两侧的键。当中央键呈现S1时，啄左键是“正确的”，当呈现S2时，啄右键是“正确的”。正确反应会产生强化，错误反应会导致3秒的黑屏。在三种程序下测量检测性能。第一种是标准信号检测设计，其中S1的概率变化，对S1正确反应获得强化的次数允许随之变化。在第二种程序中，S1概率再次变化，但两种选择之间的强化分布保持相等。在第三种程序中，S1的概率保持不变，而强化分布在两种选择之间变化。反应偏差的变化是选择反应相对强化率变化的函数而非刺激呈现概率变化的函数。在这三种程序中辨别力保持不变。
