Reilly Mark P, Posadas-Sánchez Diana, Kettle Lauren C, Killeen Peter R
Arizona State University, United States.
Behav Processes. 2012 Nov;91(3):236-43. doi: 10.1016/j.beproc.2012.09.002. Epub 2012 Sep 16.
Three experiments investigated foraging by rats and pigeons. In Experiment 1, each response on a manipulandum delivered food to a cup, with the distance between the manipulandum and the cup varying across conditions. The number of responses made before traveling to collect and eat the food increased with distance for rats, but not for pigeons. In Experiment 2, two manipulanda were placed at different distances from a fixed food source; both pigeons and rats preferentially used the manipulandum closest to the food source. Experiment 3 was a systematic replication of Experiment 1 with pigeons. In different conditions, each peck on the left key increased the upcoming hopper duration by 0.5, 1.5 or 2.5s. Completing a ratio requirement on the right key of 1, 4, 8, 16 or 32 pecks, depending on the condition, then produced the food hopper for a duration that depended on the number of prior left pecks. As the ratio requirement increased on the right key, pigeons responded more on the left key and earned more food. Overall, the results replicate previous research, underlining similarities and differences between these species. The results are discussed in terms of optimal foraging, reinforcer sensitivity and delay discounting.
三项实验研究了大鼠和鸽子的觅食行为。在实验1中，对操作柄的每次反应都会将食物送到一个杯子中，操作柄与杯子之间的距离在不同条件下有所变化。对于大鼠来说，在前往收集和食用食物之前所做出的反应次数随着距离的增加而增加，但鸽子并非如此。在实验2中，两个操作柄被放置在距离固定食物源不同的位置；鸽子和大鼠都优先使用最靠近食物源的操作柄。实验3是对实验1用鸽子进行的系统重复。在不同条件下，每啄一次左键会使即将出现的食槽持续时间增加0.5、1.5或2.5秒。根据条件，在右键上完成1、4、8、16或32次啄击的比率要求，然后会产生一个持续时间取决于先前左键啄击次数的食物食槽。随着右键上比率要求的增加，鸽子对左键的反应更多，获得的食物也更多。总体而言，结果重复了先前的研究，强调了这些物种之间的异同。从最优觅食、强化物敏感性和延迟折扣的角度对结果进行了讨论。
