Elsmore T F, McBride S A
Division of Neuropsychiatry, Walter Reed Army Institute of Research, Washington, D.C. 20307-5100.
J Exp Anal Behav. 1994 May;61(3):331-48. doi: 10.1901/jeab.1994.61-331.
In two experiments conducted in an eight-arm radial maze, food pellets were delivered when a photocell beam was broken at the end of each arm via a nose poke, according to either fixed-interval or random-interval schedules of reinforcement, with each arm providing a different frequency of reinforcement. The behavior of rats exposed to these procedures was well described by the generalized matching law; that is, the relationships between log behavior ratios and log pellet ratios were approximated by linear functions. The slopes of these log-log functions, an index of sensitivity to reinforcement frequency, were greatest for nose pokes, intermediate for time spent in an arm, and least for arm entries. Similar results were obtained with both fixed-interval and random-interval schedules. Addition of a 10-s changeover delay in both experiments eliminated the slope differentials between nose pokes and time spent in an arm by reducing the slopes of the nose-poke functions. These results suggest that different aspects of foraging may be differentially sensitive to reinforcement frequency. With concurrent fixed-interval schedules, the degree of temporal control exerted by individual fixed-interval schedules was directly related to reinforcement frequency.
在两项在八臂放射状迷宫中进行的实验里，根据固定间隔或随机间隔强化程序，当光电池光束在每只臂末端被通过鼻触打破时给予食物颗粒，每只臂提供不同的强化频率。暴露于这些程序的大鼠的行为很好地符合广义匹配定律；也就是说，对数行为比率与对数颗粒比率之间的关系由线性函数近似。这些对数-对数函数的斜率，作为对强化频率敏感性的指标，对于鼻触最大，对于在一只臂中花费的时间居中，对于进入臂的次数最小。固定间隔和随机间隔程序都得到了类似结果。在两项实验中添加10秒的转换延迟，通过降低鼻触函数的斜率，消除了鼻触和在一只臂中花费时间之间的斜率差异。这些结果表明，觅食的不同方面可能对强化频率有不同的敏感性。在同时进行固定间隔程序时，各个固定间隔程序施加的时间控制程度与强化频率直接相关。
