Response–reinforcer contiguity versus response-rate–reinforcer-rate covariance in rats' lever pressing: Support for a multiscale view

The multiscale molar view sees behavior as a flow, like a river, extended in time. Matching theory expresses the way activities compete for time. Relative time taken by any activity depends on relative induction. The present experiment tested matching theory applied to concurrent contingent and noncontingent food. As adjunctive activities that compete with operant activity, we recorded hopper head entries and presses on a lever near the food hopper that had no programmed consequences. Eight naïve rats were first exposed to a variable-time 60 s schedule, which across conditions was gradually transformed into a variable-interval 60 s schedule by increasing the proportion of food that was delivered contingent on pressing a lever far from the hopper. Another group of 4 rats that had been trained to press a lever near a food hopper were introduced in the second condition, in which one food delivery was contingent on far-lever pressing. We found induction following a power function to describe pressing on the far lever (operant activity). Matching theory combined with power-function induction also accounted for adjunctive activity. Results with single contingent food deliveries provided little support for the molecular view that behavior consists of discrete responses “strengthened” by immediately following reinforcers.     

The stability and flexibility of spatial categories

Four experiments examined the flexibility and stability with which children and adults organize locations into categories based on their spatiotemporal experience with locations. Seven-, 9-, 11-year-olds, and adults learned the locations of 20 objects in an open, square box. During learning, participants experienced the locations in four spatiotemporally defined groups (i.e., four sets of nearby locations learned together in time). At test, participants attempted to place the objects in the correct locations without the aid of the dots marking the locations. Children and adults displaced the objects toward the corners of the box consistent with the organization they experienced during learning, suggesting that they used spatiotemporal experience to organize the locations into groups. Importantly, the pattern of organization remained the same following a long delay for all four age groups, demonstrating stability. For adults, this organization shifted after a new pattern of spatiotemporal experience was introduced, suggesting that adults' categories based on spatiotemporal experience are quite flexible. Children only exhibited flexibility when the new pattern of spatiotemporal organization was consistent with available perceptual cues, demonstrating that the flexibility with which children organize locations into categories is intimately tied to both remembered and perceptual sources of information.     

Discrimination of response-reinforcer and response-stimulus contingencies in pigeons

For three pigeons (Experiment 1), the presentation of a red response key ended with a food presentation either following two responses separated by at least 10 seconds (a DRL contingency) or following a 10-second response-free period (a DRO contingency). For three other birds (Experiment 2), a brief stimulus presentation terminated the DRL and DRO contingencies. A white side key was presented next and ended with response-dependent food following one contingency and a timeout following the other. Since the contingency on the red key was unsignaled, differential responding on the white side key could indicate that the two response-reinforcer relations had been discriminated. In Experiment 1, the red-key duration and number of responses influenced white-key responding following the contingency that predicted the timeout. A response-initiated DRO was instated, and the influence of red-key duration and response number on white-key responding was diminished. In both experiments, the 10-second time criterion in both contingencies was varied from 0.34 second to 10 seconds. Even at short time intervals the DRO and DRL contingencies were readily discriminated. Pigeons tended to class the two contingencies according to a rule that did not involve simply stimulus duration, numbers of responses, or even the time between a response and its consequence.     

Interresponse-time punishment: a basis for shock-maintained behavior.

Lever pressing of squirrel monkeys postponed brief electric shock according to a free-operant shock-postponement procedure. Pressing also produced shock with a probability proportional to the duration of the current interresponse time in some conditions, or to the fifth ordinally-preceding interresponse time in others. These conditions provided equal frequencies and temporal distributions of response-produced shocks either contingent on or independent of the current interresponse-time duration, respectively. Shock delivered contingent on the current interresponse-time duration resulted in shorter mean interresponse times and higher overall response rates that shock delivered independent of the current interresponse time. In subsequent conditions, response-produced shocks were sufficient to maintain responding following suspension of the postponement procedure only when those shocks were contingent on the current interresponse time. Presenting shock independent of the current interresponse time, conversely, suppressed response rate and ultimately led to cessation of responding in the absence of a conjoint shock-postponement procedure. These results demonstrate interresponse-time punishment in the absence of any indirect avoidance contingencies based on overall shock-frequency reduction, and strongly support similar interpretation at the more local level of shock-frequency reduction correlated with particular interresponse times. Differential punishment of long interresponse times also provides both an a priori basis for predicting whether a schedule of shock presentation will maintain or suppress responding and a framework for interpreting many of the functional relations between overall response rate and parameters of consequent shock presentation. Finally, these results and others indicate the importance of response-consequence contiguity above and beyong any notion of noncontiguous contingency in the control of behavior.     

邻近效应对多媒体学习中图文整合的影响:线索的作用

在多媒体学习中图文排列的邻近或远离会影响学习的效果。本研究操纵了多媒体呈现的图文排列位置,采用颜色作为线索引导注意,探讨了线索有无和图片-文字的空间位置对多媒体学习图文整合的影响。结果发现:图文邻近呈现时的保持测验和迁移测验成绩好于图文远离呈现,图文邻近呈现时学习者对关键兴趣区的进出次数更多,体现出以文字为导向的阅读模式。线索并没有单独影响学习成绩和注意分配;但结合图文位置后,发现有线索时图文邻近学习材料的注视次数、进出关键兴趣区的次数显著多于图文远离。研究认为:图文的邻近效应不仅提高学习者对知识的识记和理解,同时也影响了学习者的注意分配过程,图文邻近呈现有助于图片和文本信息的注意联结和知识整合;线索能使邻近效应得到凸显,更好地促进图文信息的注视加工,但没有改进学习的效果。     

RESPONSE-REINFORCER RELATIONSHIPS AND IMPROVED LEARNING IN AUTISTIC CHILDREN

In order to affect more rapid response acquisition for autistic children, researchers have recently begun to investigate the functional relationships of reinforcers to other components of the operant conditioning paradigm. Previous research suggested that functional relationships between target behaviors and reinforcers might be especially effective. For example, locating a reward inside a container might be a more efficient way to teach a child to open the container than by handing the child a reward for opening an empty container. The present experiment assessed, within a multiple baseline design, the possibility of improving autistic children's learning by changing arbitrary response-reinforcer relationships (while holding target behaviors and reinforcers constant) so that the target behaviors became functional (i.e., a direct part of the response chain required for the child to procure the reinforcer). The results showed that: (1) arranging functional response-reinforcer relationships produced immediate improvement in the children's learning, and resulted in rapid acquisition of criterion level responding; and (2) high levels of correct responding initially produced by functional response-reinforcer relationships were continued even when previously ineffective arbitrary response-reinforcer conditions were reinstated. The results are discussed in terms of understanding and improving autistic children's learning.     

The effects of unsignalled delayed reinforcement

Pigeons' pecks were reinforced according to a variable-interval schedule. A delay-of-reinforcement procedure was then added to the schedule, or a yoked-control procedure was arranged where the reinforcers occurred independently of responding according to the same variable-interval schedule. During the delay-of-reinforcement procedure, the first peck after a reinforcer was scheduled began a delay timer and the reinforcer was delivered at the end of the interval. No stimulus change signalled the delay interval and responses could occur during it, so that the obtained delays were often shorter than those scheduled. Responding under this procedure was highly variable but, in general, behavior was substantially reduced even with the shortest delay used, 3 sec. In addition, the rates maintained by delayed reinforcement were only slightly greater than those maintained by the yoked-control procedure, suggesting that adventitious pairings of response and reinforcer were responsible for some of the maintenance of behavior that did occur. The results challenge recent conceptions of reinforcement as involving response-reinforcer correlations and re-emphasize the role of temporal proximity between response and reinforcer.     

Associative interaction: joint control of key pecking by stimulus-reinforcer and response-reinforcer relationships

The joint control of rate of key pecking in pigeons by stimulus-reinforcer and response-reinforcer relationships was studied in the context of a two-component multiple schedule of reinforcement. Food presentation was always associated with one component and extinction with the other. The stimulus-reinforcer relationship was manipulated by varying the relative durations of the two components. In the food-presentation component, a fixed rate of reinforcement, independent of rate of responding, was generated by a schedule referred to as “T*”. One aspect of the response-reinforcer relationship, contiguity, was manipulated by varying the percentage of delayed reinforcers. With the multiple T* extinction schedule, stimulus-reinforcer and response-reinforcer relationships could be varied independently of one another. Rate of key pecking was sensitive to manipulations of both relationships. However, significant differential effects due to either the stimulus-reinforcer or response-reinforcer relationship were obtained only when the other relationship was weak: stimulus-reinforcer and response-reinforcer relationships interacted in the joint control of responding.     

Stimulus- and response-reinforcer contingencies in autoshaping, operant, classical, and omission training procedures in rats

Separate groups of rats received 500 trials of lever-press training under autoshaping (food delivery followed 10-second lever presentations, or occurred immediately following a response); operant conditioning (responding was necessary for food delivery); and classical conditioning (food followed lever presentations regardless of responding). Each group then received 500 trials on an omission procedure in which food was omitted on trials with a response. Another group received 1000 trials on the omission procedure, and a fifth group, random control, received 1000 uncorrelated presentations of lever and food. The autoshaping, operant, and classical groups reached high response levels by the end of initial training. Acquisition was fastest in the autoshaping group. Responding remained consistently low in the control group. The omission group responded at a level between the control group and the other three groups. During omission training, responding in these three groups declined to the omission-group level. During omission training, the rats continued contacting the lever frequently after lever pressing had declined. Response maintenance under omission training seems not to require topographic similarity between the response and reinforcer-elicited consummatory behaviors.     

College students' responding to and rating of contingency relations: The role of temporal contiguity

Two experiments investigated the role of temporal contiguity in college students' responding to and rating of contingency relations during operant conditioning. Schedules were devised that determined when but not whether appetitive or aversive events would occur. Subjects' reports concerning the schedules were obtained by means of a 200-point rating scale, anchored by the phrases “prevents the light from occurring” (−100) and “causes the light to occur” (+100). When tapping a telegraph key advanced the time of point gain, responding was maintained or increased and subjects gave positive ratings. When tapping a telegraph key advanced the time of point loss, subjects also gave positive ratings, but responding now decreased. When key tapping delayed the time of point gain, responding decreased and subjects gave negative ratings. When key tapping delayed the time of point loss, subjects also gave negative ratings, but responding now increased. These findings implicate response-outcome contiguity as an important contributor to causal perception and to reinforcement and punishment effects. Other accounts—such as those stressing the local probabilistic relation between response and outcome or the molar correlation between response rate and outcome rate—were seen to be less preferred interpretations of these and other results.