Cultural transmission of irrelevant tool actions in diffusion chains of 3- and 5-year-old children

We used the diffusion chain method in order to investigate whether irrelevant actions would be transmitted along chains of 3- and 5-year-old children. Four chains of eight children witnessed a trained “expert” child perform a sequence of actions in order to retrieve a reward from either a transparent or an opaque puzzle box. The action sequence involved both goal relevant and goal irrelevant actions. In the transparent box chains the participants could potentially determine which of the actions were irrelevant as the causal effects were clearly visible. Results indicated that irrelevant actions transmitted down chains of 3-year-old children irrespective of box transparency. In contrast, irrelevant actions dropped out of the transparent box chain extremely quickly at 5 years, but were maintained within the opaque chain. These findings highlight the power of the diffusion chain method as a tool for exploring cultural learning.     

Gross-motor skill acquisition by preschool dance students under self-instruction procedures

The effects of two training procedures--(a) modeling and praise and (b) self-instruction, modeling, and praise--on complex gross-motor chain acquisition for preschool dance class students were evaluated. Six girls participated in the study. A multiple baseline design across six gross-motor chains with a secondary group comparison for treatment order effects was used. Both procedures were effective in teaching the gross-motor chains. Nevertheless, for 4 of the 6 participants, the self-instruction procedure produced a faster acquisition rate in at least two of the three comparable pairs of gross-motor chains. Furthermore, very early in gross-motor chain acquisition, for five of the six gross-motor chains, the self-instruction condition was associated with faster response acquisition.     

Effects of altering outcome expectancies on pigeons' delayed conditional discrimination performance

An outcome-expectancy mediation theory of learning was tested in a series of transfer experiments with pigeons. The principal technique employed was a delayed two-choice conditional discrimination in which the subject's correct choice yielded a food reward on one kind of trial and a feedback tone on the other. According to the theory, this task engenders two-link mediational chains in that each conditional cue controls a particular outcome expectancy (S-E link) and the expectancy, in turn, cues a specific choice response (E-R link). Relative to the hypothetical mediators established by preceding training, transfer problems required either the same mediational chains, the alteration of one link in each chain, or the alteration of both links in both chains for optimal performance. The results of four separate transfer experiments confirmed detailed theoretical predictions, including that of an unusual nonmonotonic transfer effect. The relation of the present theory to earlier mediation theories is discussed.     

Temporal alternation in the white rat?

Four white rats were reinforced after 15 then 45 then 15 then 135 (or 5) responses to a bar under a single exteroceptive stimulus condition. Three came to make long pauses before the longest ratio in the schedule but not before any of the others. Four other rats were reinforced after alternate response chains each made on two bars. The first chain was FR5FR5 for all subjects, the second FR5FR40 for two, and FR40FR5 and FR20FR5 for one subject each. Subjects reinforced on schedule mix (chain FR5FR5 chain FR5FR40) both paused longer after the first than after the second chain relatively early in training. Later, the subject reinforced on mix (chain FR5FR5 chain FR40FR5) also paused longer after the first chain, but pauses of the fourth subject were equally short after both chains. When the ratios in the second chain were reversed the two subjects now reinforced on mix (chain FR5FR5 chain FR40FR5) paused much longer after the first chain, but the other two paused only slightly longer after the first than after the second chain.     

Probability of response and probability of reinforcement in a response-defined analogue of an interval schedule

Variable interval (VI) responding was hypothesized to be a function of differential reinforcement susceptibilities of various unspecified behavior chains that mediate interresponse times (IRTs). To test this hypothesis, probabilities of reinforcement were regulated for the lengths of chains of key pecking responses of pigeons, analogous to the way that VI regulates probabilities of reinforcement for IRTs. This procedure generated a number of VI-like effects, supporting the notion that VI behavior can be construed as a special case of an interaction between the organism's function relating reinforcement susceptibilities to chain length and the experimenter's function relating probabilities of reinforcement to chain length.     

The role of transmission biases in the cultural diffusion of irrelevant actions

This study used a diffusion chain paradigm to explore the cultural transmission of causally irrelevant tool actions in chains of adult participants. Each chain witnessed an "expert" adult retrieve a reward from inside a puzzle box using a combination of causally relevant actions and causally irrelevant actions. Which of the actions were causally relevant was evident in two of the chains where a transparent box was used. In the other two chains, the causal effectiveness of the tool was hidden inside an opaque version of the box. Results indicated that fewer of the irrelevant actions performed by the expert model were reproduced in the transparent box chains, than the opaque box chains. However, irrelevant actions, although not in their original form, were evident within each chain suggesting that causally irrelevant tool actions can survive within groups of adults. The current article places these results, alongside those from earlier overimitation studies, within a framework of cultural evolution. The proposal here is that the social learning of irrelevant actions is heavily influenced by the interaction between various transmission biases, including frequency-based biases, model-based biases, and content-based biases. It is further proposed that the transmission bias witnessed may differ according to the interplay between characteristics of the model, characteristics of the observer, and the contents of the task.     

Analysis of factors that affect responding in a two-response chain in children with developmental disabilities

A sequence of behaviors consisting of appropriate responses, inappropriate responses, or a combination of both can be linked together in a behavior chain. Several operant processes may disrupt behavior chains. For example, one or more members of the behavior chain may be affected when reinforcement is withheld for the last response in the chain (extinction), when the last response is reinforced even if it occurs without the other responses in the chain (unchaining), or when access to the terminal reinforcer is available independent of responding (satiation). However, few studies have examined the effects of these types of procedures on responding that occurs in the context of behavior chains. The purpose of this study was to examine the effects of three clinically relevant procedures and processes (i.e., extinction, satiation, and unchaining) on behaviors that occur as part of a behavior chain. Overall, extinction and satiation resulted in a decrease in both responses in the chain. During the unchaining procedure, decreases were observed in the first response in the chain but not in the second response.     

The acquisition of behavioral chains

The present investigation was designed to study some conditions which facilitate the acquisition of behavioral chains by young children. Three experiments were performed. In Expt I subjects were required to respond overtly to the internal components of the chain. In Expt II an aversive contingency was imposed following errors. In Expt III instructions were added at the beginning of training. The results supported the following conclusions: (a) Requiring subjects to mark and name the correct stimuli on each trial increased the accuracy of performance; (b) introducing time-out contingent on incorrect responses depressed the error rate; and (c) adding instructions concerning a pending change in the experimental task resulted in a lower error rate following withdrawal of the instructional stimuli.     

PEER MODELING OF RESPONSE CHAINS: OBSERVATIONAL LEARNING BY STUDENTS WITH DISABILITIES

Peer models (classmates without disabilities) who were proficient in performing a task completed one response chain each day and described the steps they performed while their classmates with disabilities observed. Three students with disabilities participated, and their performance of the response chains was assessed immediately prior to and following the peer modeling each day. A multiple probe design across response chains, replicated across children with disabilities, was used. In addition, participation and social interactions of children with disabilities and their peer models were assessed in classroom activities after daily modeling sessions. The results indicate that the peer models performed the response chains accurately and quickly, and students with disabilities acquired the response chains. Across the study, participation in classroom activities was high, social interactions were low, and neither was affected by the peer modeling intervention.     

The effect of causal chain length on counterfactual conditional reasoning

We investigated German and Nichols' finding that 3‐year‐olds could answer counterfactual conditional questions about short causal chains of events, but not long. In four experiments (N =192), we compared 3‐ and 4‐year‐olds' performance on short and long causal chain questions, manipulating whether the child could draw on general knowledge to answer. We failed to replicate German and Nichols' result, finding instead that in two experiments (Experiments 1 and 3) there was no difference in performance on short and long causal chain questions and in two experiments (Experiments 2 and 4) children showed the opposite pattern: short causal chain questions were more difficult than long. These two unexpected patterns of results were replicated in a fifth study (N =97). Children with lower language ability found short causal chains more difficult than long. Performance by children with higher language ability was unaffected by the length of the causal chain they had to consider. We found no evidence that children showed precocious counterfactual thinking when asked about recent events in a causal chain and conclude that counterfactual thinking develops after 4 years of age.     

Extinction of a heterogeneous chain after several reinforcement schedules

Rats were conditioned to emit the following two-member chain of responses on two different operanda always available: responses on a vertical bar produced a discriminative stimulus for food-reinforced responding on a horizontal bar. Responses on the vertical bar produced a discriminative stimulus on a variable-interval 1-min schedule, and the horizontal bar produced food on a variable ratio of 10 responses. Control conditions were included in which vertical bar responses were also food-reinforced simultaneous with the onset of the discriminative stimulus for the horizontal bar response and a tandem schedule which had the same response requirements but without different exteroceptive stimuli associated with the separate components of the response chain. The latter condition greatly retarded acquisition of the response chain compared to the other schedules studied here and compared to reports in the literature on homogeneous (single operandum) response chains. Intermittent reinforcement of the chain led to greater resistance to extinction of both members and the chain remained intact longer in the sense that stimulus control was maintained.     

Responding Under Homogeneous Versus Heterogeneous Chained Schedules

Four pigeons responded under chained variable-interval schedules in which the required response topographies were either similar (i.e., a homogeneous chain) or dissimilar (i.e., a heterogeneous chain). The pigeons were exposed to all possible combinations of initial-link key pecking or treadle pressing and terminal-link pecking or treadling. Three of four birds displayed higher initial-link response rates under the homogeneous chains. These results were explained in terms of an induction effect in which the strengthening effect of reinforcing a particular terminal-link response topography generalizes to similar responses earlier in the chain but not to topographically different responses.

     

Resistance to change produced by access to fixed-delay versus variable-delay terminal links

Pigeons' responding was reinforced on a multiple schedule consisting of two two-link chain schedules presented in regular alternation. Responding in initial links (always variable-interval 60-s) produced a key-color change and access to a terminal link. The terminal link for one chain provided food after a fixed delay (fixed-interval or fixed-time); the terminal link for the other provided food after a variable delay (variable-interval or variable-time). The average duration of the terminal-link schedules was varied across conditions, but in every condition the arithmetic mean of the variable-delay terminal-link schedule was equal to the duration of the fixed delay. Response rates were higher in the initial links of the chains with the variable-delay terminal links. Response-decreasing operations (satiation, extinction) were used after performances reached asymptote. Response rates maintained by access to variable-delay terminal links tended to be more resistant to change than were rates maintained by access to fixed-delay terminal links. These results are consistent with the preference for variable- over fixed-interval terminal links observed with concurrent-chains schedules, suggesting (1) that immediacy of reinforcement influences the conditioned reinforcing potency of access to a terminal link and (2) that choice in concurrent chains and resistance of responding to change may be manifestations of the same effect of reinforcement.     

The effect of behavioral skills training with general‐case training on staff chaining of child vocalizations within natural language paradigm

This study used behavioral skills training (BST) and general‐case training (GCT) in which the experimenter simulated child performance to teach three staff to conduct NLP and response chaining to increase three‐link vocal chains in three children with autism. Staff increased their correct NLP performance during post‐training in comparison to baseline. Two of three children emitted more vocal chains following training. This study demonstrated that BST and GCT were effective in training NLP and response chaining. When assessing social validity, both Board Certified Behavior Analysts (BCBAs) and teachers did not indicate an increase in staff members' teaching skills. Future research should develop effective technologies to chain vocal behavior and to teach staff and parents to implement response chaining. Copyright © 2009 John Wiley & Sons, Ltd.     

Value of conditioned reinforcers as a function of temporal context

In two experiments, pigeons were trained on a multiple-chain schedule, in which the initial link for one chain was a variable-interval (VI) 100 s schedule and for the other chain a VI 10 s schedule. The terminal links were both fixed-time 30 s schedules signaled by differently colored stimuli. Following training, the pigeons had their preference for the terminal-link stimuli tested either by presenting these stimuli in concurrent probes or by presenting these stimuli as reinforcement for completing novel initial links. In Experiment 1, pigeons significantly preferred the terminal-link stimulus that followed the long initial link in three of the five conditions. This preference was observed across all three testing procedures (concurrent chains, concurrent chains probes, and concurrent probes). Experiment 2 was a replication of this effect in one of the conditions from Experiment 1. The results demonstrate that temporal context does impact the value of a conditioned reinforcer in a manner consistent with delay-reduction theory, and inconsistent with other choice theories, such as the contextual choice model and scalar expectancy theory.     

Choice with uncertain outcomes: conditioned reinforcement effects.

Pigeons responded on concurrent chains with equal initial- and terminal-link durations. In all conditions, the terminal links of one chain ended reliably in reinforcement; the terminal links on the alternative chain ended in either food or blackout. In Experiment 1, the terminal-link stimuli were correlated with (signaled) the outcome, and the durations of the initial and terminal links were varied across conditions. Preference did not vary systematically across conditions. In Experiment 2, terminal-link durations were varied under different stimulus conditions. The initial links were variable-interval 80-s schedules. Preference for the reliable alternative was generally higher in unsignaled than in signaled conditions. Preference increased with terminal-link durations only in the unsignaled conditions. There were no consistent differences between conditions with and without a common signal for reinforcement on the two chains. In the first series of conditions in Experiment 3, a single response was required in the initial links, and the stimulus conditions during 50-s terminal links were varied. Preference for the reliable outcome approached 1.0 in unsignaled conditions and was considerably lower (below .50 for 3 of 5 subjects) in signaled conditions. In a final series of signaled conditions with relatively long terminal links, preference varied with duration of the initial links. The results extend previous findings and are discussed in terms of the delay reduction signaled by terminal-link stimuli.     

Preference for fixed-interval terminal links in a three-key concurrent chain schedule

Pigeons were trained on three-key concurrent chain schedules in which the initial links were variable-interval schedules and the terminal links were fixed-interval schedules. In the first experiment, the initial links were all equal and the terminal-link schedule on one key only was varied. In the second part of the experiment, the terminal-link schedules were all fixed, but different, and the initial-link schedule on one key was varied. Relative response rates in the initial links did not match either the relative arranged, nor the relative obtained, terminal-link reinforcement rates. The relations between independent and dependent variables in three-key concurrent chains were similar to, but not identical with, those found in two-key chains comprising the same schedule types.     

Interaction-priming: a method of reinstating patient-family relationships

The probability of successful discharge for long-term mental hospital patients has been found to depend on strong family and social relationships (Chapman, Day and Burstein, 1961 ; Chase and Silverman, 1943; Paul, 1969; Meichenbaum, 1966; Ullmann, 1967). Yet, long-term institutionalization often results in the weakening of these relationships. These findings suggest that successful discharge would be facilitated by procedures that maintained or restored these social relationships. The present study attempted to develop such a procedure, based on the principles of Response Priming (O'Brien, Azrin and Henson, 1969) and Reinforcer Sampling (Ayllon and Azrin, 1968). Response Priming views complex behavior such as family visits as chains of responses and states that the probability of the completion of the chain (visit) increases during later portions of the chain. The present procedure applies this principle by not requiring visitors to engage in those behaviors remote from the completion of the chain, but rather, by making visits available to them at the terminal portion of the chain. This was done by not requiring visitors to come to the hospital to visit the patient, but rather, by directly transporting the patient to the visitor's home. The Reinforcer Sampling rationale (Ayllon and Azrin, 1968) suggests that future visits would likely increase if visits were reinforcing to the family and the patient. Thus, the patients' behavior was analyzed during visits in the families' homes. Between visits, instruction was given to the patients for improving the reinforcing quality of these types of behavior for subsequent visits. The rationale was that the Response Priming Procedure would produce visits and the Reinforcer Sampling Procedure would show the families and patients that being together was enjoyable. The relationships should, therefore, be maintained and, hopefully, thereby increase the likelihood of successful discharge for the long-term hospitalized patients.