Visually guided catching and tracking skills in pigeons: A preliminary analysis

Research on reaching, tracking, and catching in the pigeon has been hampered by limitations of technology. A new system was developed in which the target was a small rectangle presented on a video display terminal and the pecking response was detected with touch technology. The target moved up and down vertically with sinusoidal velocity. A coincidence between the location of the pigeon's beak and the cursor produced reinforcement. The pigeon pecked ahead and behind the target, but most pecks occurred behind the target so the dominant tracking strategy was lagging. The pigeon was adept at “catching” the target at many locations throughout the trajectory. Transfer of motor learning was tested on probe trials during which the trajectory changed from vertical to horizontal. On transfer trials the pigeons' dominant pattern of pecking immediately shifted from vertical to horizontal. The motor skill displayed by the pigeons was flexible and adaptive, suggesting that the pigeons had learned to track the cursor.     

THE USE OF BEHAVIORAL ASSESSMENT TO PRESCRIBE AND EVALUATE TREATMENTS FOR SEVERELY HANDICAPPED CHILDREN

Behavioral assessment procedures were used to prescribe and evaluate treatments of maladaptive behavior for 2 children with severe multiple handicaps. In Experiment 1, the results of an assessment of reinforcer preference were used in conjunction with a functional analysis of the conditions maintaining self-injurious behavior to prescribe a treatment for a child with severe disabilities. The treatment procedure involved the use of a pressure-sensitive microswitch to activate reinforcing stimuli during two solitary conditions, during which self-injurious behavior had occurred at high rates. The results were evaluated with a multiple baseline across settings design and indicated that self-injury decreased with concomitant increases in microswitch activation. Results were maintained at 6 weeks, 8 weeks, and 6 months. In Experiment 2, the results of behavioral assessments of reinforcer preference and self-injurious behavior were combined to develop a treatment for a second severely handicapped child, who exhibited high rates of self-injury in demand situations. This treatment was evaluated with a multiple baseline across tasks design and resulted in the elimination of self-injury for up to 15 months.     

GENERALIZED LANGUAGE LEARNING BY CHILDREN WITH SEVERE MENTAL RETARDATION: EFFECTS OF PEERS' EXPRESSIVE MODELING

In this study, we investigated the conditions that contribute to observational learning of generalized language in children with severe mental retardation. Matrix-training strategies were used to teach 6 children with mental retardation to combine known words into two- or three-word utterances consistent with syntactic rules. Subsequently, the children learned two or more unknown words concurrently, inducing word-referent relations consistent with these word order rules. Generalized learning of responses not taught directly was shown to be under experimental control using a multiple baseline design across submatrices. Expressive modeling of only four or five responses was sufficient to promote recombinative generalization in the expressive and receptive modalities. Thus, 95% to 98% of subjects' learning was attributed to generalization processes. This study demonstrates how the efficiency of language training with children with mental retardation might be enhanced by coupling observational learning and matrix-training strategies.     

DISTRACTION: ITS UTILIZATION AND EFFICACY WITH CHILDREN UNDERGOING DENTAL TREATMENT

We investigated the utilization and efficacy of distraction in reducing the anxious and disruptive behavior of 4 children undergoing dental treatment. During the distraction procedure, the children were shown a poster and told a story about it during dental treatment. They earned a prize if they attended to the poster and story and could correctly answer questions about them following each intervention visit. The children's disruptive behavior was assessed via direct observation, and results were analyzed within a multiple baseline design. The children exhibited high levels of anxious and disruptive behavior across baseline visits, regardless of the length of time in treatment or number of visits. Anxious and disruptive behavior decreased upon introduction of the intervention for all children. This was accompanied by the children meeting the criterion for correct answers on the distraction quiz. However, 2 of the children demonstrated an increase in their anxious and disruptive behavior across intervention visits. Results are discussed in terms of the need to evaluate treatment strategies that promote maintenance as well as initial changes.     

Complex decision making: A longitudinal study of process and performance

Two studies using a computer-simulated, strategy-formulation game and business students were conducted using simultaneous verbal protocols. It was found that a number of information-processing and information-evaluation thought processes were significantly related to game performance. Consistent with what is known about individual decision making, the present results suggest that, for the task used in this study, individuals who engage in causal analysis perform better than those who do not. But those who focus on negative emotions, blindly repeat previously successful decisions, and engage in illogical through processes perform more poorly than those who do not. Causal replication using real managers within organizational settings, however, is needed before firm conclusions can be drawn from this research.     

Conceptualizations of valence and instrumentality: A fourfold model

Within the framework of valence-instrumentality (VI) theory, a fourfold model is developed to predict the contribution which is made by one outcome of an alternative to the valence of that alternative. The proposed model uses four subjective conditional probabilities which are based on the presence and absence of an alternative, and on the occurrence and nonoccurrence of an outcome. Valence is defined as the difference between the attractiveness values of the occurrence of an alternative (or an outcome) and the nonoccurrence of an alternative (or an outcome). Also, differences between subjective probabilities replace instrumentalities. Alternative valence-instrumentality formulations are analyzed in relation to the proposed fourfold model. The proposed model can be understood as a consistent application of Vroom's model (1964, Work and motivation, New York: Wiley), while other models are judged to be relatively deficient. The fourfold model, in combination with a matrix formulation of expectancy concepts, addresses a number of criticisms of VI theory and makes possible a test of the theory within the limits of its own assumptions.     

The effects of social motives on behavior in social dilemmas in two cultures

Subjects in Santa Barbara, California, and Groningen, The Netherlands, participated in a seven-person social dilemma game, presented in terms of a conservation of resources problem. Prior to their decision making in the social dilemma game, subject's social motive (altruistic, cooperative, individualistic, competitive) was assessed by means of two different classification procedures. On the basis of previous research findings American subjects were expected to display relatively more competitive social motives, and Dutch subjects relatively more cooperative ones. However, no indications of crosscultural differences were found neither with regard to the distribution of social motives nor with regard to the amount of resources taken for self in the social dilemma game. In both locations, competitive subjects took most resources for self, individualistic subjects took next most, cooperative subjects took less than individualists, and altruistic subjects took the least. In addition to predictive validity, indices of the convergent validity of two social motive assessment procedures were described.     

Expectations,procedural justice,and alternative reactions to being deprived of a desired outcome

People often find that they do not have some positive outcome they once expected to obtain, while others around them have attained that outcome. Two experiments were conducted to assess how four possible responses to such a situation are affected by procedural justice (i.e., the fairness of the procedures by which the object was denied) and by one's expectations about obtaining the outcome in the future. The four possible responses examined were anger responses, achievement strivings, devaluation of the object (X), and self-deprecation. A repeated-measures analysis revealed that the dependent variables were differentially affected in Study 1, but less so in Study 2. Analyses further revealed effects of procedural justice, such that unfair procedures led to more anger, lower achievement strivings, greater devaluation of X, and (in Study 1 only) marginally less self-deprecation. Expectations had only a marginal affect on achievement strivings in Study 1, and an effect on self-deprecation in Study 2, with higher expectations leading to lower achievement strivings and less self-deprecation, respectively. Procedural justice and expectations interacted to affect subjects' derogation of the agent who deprived them (Study 1) and their devaluation of X (Study 2). Implications for future research and for theoretical development are discussed.     

Expectancy,integration, and interactional processes: Age differences in the nature of words affected by sentence context

Two experiments investigated sentence context effects on the naming times of sentence completion words by third-grade children and college students. Across both experiments, the largest age difference in contextual facilitation was obtained for highly predictable, best completion words. Pronounced age differences in facilitation effects were also present for semantically acceptable target words which were much less predictable in the sentence context than the best completion words. However, age differences in contextual facilitation were negligible for target words which were associatively related to the best completion word, but which were not also semantically acceptable in the sentence context. Thus, the semantic acceptability of the word in the sentence context had a much greater influence on children's as compared to adults' word identification times, both when the word was highly predictable, as well as when it was much less predictable in the sentence context.     

Development of organization in recall: A stages-of-learning analysis

An experiment is reported in which the effects of taxonomic organization on 7-year-old and 11-year-old children's free and cued recall of two- and four-category lists were examined. The data were analyzed using a stages-of-learning model that simultaneously delivers estimates of the impact of these manipulations on storage and retrieval components of recall. The results indicated that for the Grade 2 children providing a category label at the time of recall primarily enhanced storage whereas increasing the number of categories primarily enhanced retrieval. For Grade 6 children, on the other hand, the use of category labels to cue recall primarily enhanced retrieval, whereas increasing the number of categories affected both storage and retrieval in free recall, but only retrieval in cued recall. In addition, while older children were superior to younger children at both storing and retrieving information, age differences at retrieval were generally larger than those at storage.