Rats and pigeons exhibit different extinction profiles after instrumental acquisition with large vs. small rewards. In rats, extinction is faster after large-reward training, but in pigeons, extinction is faster after small-reward training. Two experiments extended these findings to a progressive-ratio schedule with acquisition training with two reward magnitudes administered either between or within subjects. Both rats and pigeons, under both between- and within-subject conditions, exhibited higher breakpoints (the last completed ratio) when responding for 5 pellets per ratio vs. 1 pellet per ratio. However, between-subject training yielded faster extinction after training with 5 pellets than 1 pellet for rats, but the opposite trend for pigeons. Extinction effects were eliminated in within-subject training for rats, but remained unchanged for pigeons. These results are discussed in the context of frustration theory and the strengthening/weakening principle of learning.

老鼠和鸽子在获得工具后会表现出不同的灭绝模式，并获得大或小奖励。在大鼠中，大奖励训练后灭绝更快，但是在鸽子中，小奖励训练后灭绝更快。两项实验将这些发现扩展到了具有进阶训练的渐进式进度表，并在受试者之间或受试者内部给予了两种奖励幅度。在受试者之间和受试者内部条件下，大鼠和鸽子在响应每个比率5个颗粒相对于每个比率1个颗粒时都表现出更高的断点（最后完成的比率）。然而，受试者之间的训练在使用5个小球进行训练之后产生的灭绝速度比对1个小球进行了训练，但是对于鸽子来说则相反。在大鼠内部训练中消除了灭绝作用，但对鸽子却保持不变。在沮丧理论和学习的强化/减弱原理的背景下讨论了这些结果。