Flory R K, Blosser S L
Physiol Behav. 1985 Mar;34(3):341-8. doi: 10.1016/0031-9384(85)90193-3.
Pigeons were exposed to complex fixed-ratio schedules to assess whether the temporal location of schedule-induced attack was controlled by the discriminative properties of food or by the aversive aftereffects of food withdrawal. When exposed to a multiple fixed-ratio 25 fixed-ratio N schedule in which either fixed-ratio component occurred with equal probability according to a quasi-random sequence and in which the value of N ranged from 115 to 150 across subjects, all pigeons exhibited post-food attack against a rear-projected conspecific target predominantly at the signalled onset of the higher-valued ratio component. Exposure of subjects to a mixed fixed-ratio 25 chained fixed-ratio 25 fixed-ratio N-25 schedule, however, resulted in a shift of attack to the signalled onset of the fixed-ratio N-25 component rather than following food. A chained fixed-ratio 25 fixed-ratio N-25 schedule induced attack predominantly after food delivery rather than at the onset of the fixed-ratio N-25 component. These findings show that the temporal locus of schedule-induced attack is primarily controlled by a stimulus, whether food delivery or key color change, that reliably precedes a relatively long period of reinforcer unavailability.
鸽子被置于复杂的固定比率时间表中，以评估时间表诱导攻击的时间定位是由食物的辨别特性控制，还是由食物剥夺的厌恶后效控制。当鸽子被置于多重固定比率25固定比率N的时间表中时，根据准随机序列，两个固定比率成分出现的概率相等，且N的值在不同个体间从115到150不等，所有鸽子都主要在高价值比率成分的信号开始时，对后投射的同种目标表现出食物后攻击。然而，将实验对象置于混合固定比率25链接固定比率25固定比率N - 25的时间表中，导致攻击转移到固定比率N - 25成分的信号开始时，而不是在食物之后。链接固定比率25固定比率N - 25的时间表主要在食物投递后而不是在固定比率N - 25成分开始时诱导攻击。这些发现表明，时间表诱导攻击的时间位点主要由一个刺激控制，无论是食物投递还是按键颜色变化，该刺激在相对较长的强化物不可用期之前可靠地出现。
