Blocking acquisition of the rabbit's nictitating membrane response to serial conditioned stimuli

Three experiments demonstrated that prior training with one stimulus (CS1) would block acquisition of the rabbit's nictitating membrane response (NMR) to another stimulus (CS2) which was more contiguous to the US during serial compound training (CS1-CS2-US). Specifically, the CS1-US interval was 800 msec, which produces only a modest rate of CR acquisition, while the CS2-US interval was 400 msec, which is an optimal value for the NMR preparation. Experiment 1 demonstrated blocking when CS1 overlapped CS2, and Experiment 3 demonstrated blocking when CS1 and CS2 were presented in a strictly sequential fashion. Experiment 2 showed that the magnitude of blocking in the serial compound was comparable to that obtained in a simultaneous compound in which both the CS1-US and CS2-US intervals were 800 msec, thus making CS2 less contiguous with the US than in the serial compound. Moreover, the level of responding to CS2 in all serial compound groups (blocking and control) was lower than in the simultaneous compound groups. The present findings provide further evidence that the associative consequences of CS-US contiguity can be highly attenuated by processes of attention or competition for associative strength.     

Discrete dynamic choice: An extension of the choice models of thurstone and luce

The present paper deals with the extension of two well-known static discrete choice theories to the dynamic situation in which individuals make choices at several points in (continuous) time. A dynamic version of Luce's Axiom, “independence from irrelevant alternatives”, is proposed and some of its implications are derived. In the static case Yellott (J. Math. Psych. 1977, 15, 109–146) and others have demonstrated that an independent random utility model generated from the extreme value distribution exp(?e^?ax?b) becomes equivalent to Luce's Axiom. Yellott also introduced an axiom called “invariance under uniform expansions of the choice set”, and he proved that within the class of random utility models with independent identically distributed utilities (apart from a location shift) this axiom is equivalent to Luce's Axiom. These results are extended to the dynamic situation and it is shown that if the utility processes are expressed by so-called extremal processes the corresponding choice model is Markovian. A nonstationary generalization is proposed which is a substantial interest in applications where the parameters of the choice process are influenced by previous choice experience or by time-varying exogenous variables. In particular, it is demonstrated that the nonstationary model is Markovian if and only if the joint choice probabilities at two points in time have a particular form. Thus, the paper provides a rationale for applying a specific class of Markov models as the point of departure when modelling mobility processes that involve individual discrete decisions over time.     

Contrasting cases of Italian agrammatic aphasia without comprehension disorder

This study examined the effects of different concurrent verbal memory loads on a recognition accuracy task using bilaterally presented nouns. Four different memory load conditions were examined. They varied along a size dimension of either three or six words and along a complexity dimension of either easy concrete nouns or difficult highly abstract nouns. In each of the above conditions and in one control group, order or word report was controlled and in a second control group subjects were free to report the lateralized words in any order they wished. There were 20 subjects in each of the six groups. As expected, a significant right visual field superiority for verbal processing was obtained. there were no main effects of size of memory load nor complexity of m emory load on the laterality patterns. More subtle fluctuations in the patterns were found in the form of significant interactions between memory load, order of word report, and visual field. These interaction effects suggest that words reported second in the bilateral task, are more susceptible to the interfering effects of either larger or more complex memory loads. This is particularly true for right visual field words. While these data generally support a structural model of hemispheric organization, the interaction effects suggest that modifications must be made to the basic model to account for such factors as hemispheric capacity limits and order of report in the bilateral task.     

Attentional biases and the right-ear effect in dichotic listening

Most dichotic listening experiments permit subjects to deploy attention in any way they choose. We argue that this adds uncontrolled variance to the observed right-ear advantage. In the first experiment, more robust laterality effects were obtained in an identification task with focused than with divided attention. Such differences were not found in the second experiment, when a detection procedure was used. Virtually all the laterality effect observed in the second study could be attributed to subjects who were biased attenders, in the sense that they exhibited more intrusions from the right ear to the left than vice versa. However, rather than indicating that laterality effects are simply attentional bias, this effect can be attributed to an asymmetry of perceptual discrimination.     

An observational case study of failure in social problem-solving

An observationally based assessment of social problem-solving skill was contrasted with more traditional testing methods. A preschool child with low social success was chosen for a demonstration profile analysis. The relative frequencies of the social goals, strategies, and targets shown by this child during free play were plotted in relation to that of his same-sex peer group. Parallel profiles of his relative success with specific goals, strategies, and targets were also constructed and compared to relevant group means and standard deviations. Specific social problem-solving strengths and weaknesses were identified from these profiles, using both intra- and interindividual analyses. The benefits and limitations of this approach for measurement and treatment of social problem-solving deficits were discussed.     

Sex differences in the levels of generality of values/preferences related to work

The current literature on sex differences in values/preferences related to work appears polarized around two apparently contradictory sets of findings and conclusions. One set of studies fails to detect sex differences. The other set of studies indicates that males are more concerned about money, independence, security, and career goals, while females appear more concerned about people and environmental issues at work. Following W. D. Siegfried, I. MacFarlane, D. B. Graham, N. A. Moore, and P. L. Young (Journal of Vocational Behavior, 1981, 18, 30–42) it is suggested that level of analysis may be a crucial factor accounting for much of the prevailing confusion in the literature. This study investigated sex differences in values/preferences related to work at various levels of generality. A sample of 1081 senior high school students was administered the Work Aspect Preference Scale (WAPS). Complete-link cluster analyses were performed for males and females separately. Comparison of the two dendrograms reveals the substantial similarity of the preference patterns of males and females. However, the basic difference in the patterns focused on the Altruism and Physical Activity subscales. Females appeared more likely to associate helping others with personal achievement whereas males tended to see helping people in terms of controlling and organizing them. Females also linked physical activity with helping others and self-development whereas males tended to associate physical activity with extrinsic rewards of work. It is concluded that the use of cluster analysis techniques may provide the best procedure to effect an adequate reconciliation of the conflicting results to be found in the current literature.     

Evidence for the self as an imaginal prototype

This study investigated recognition memory of self-photographs which had been previously rated by subjects for their degree of reference to an imaginal prototype of “real self.” The number of false alarms to NEW photographs was found to increase with degree of self-reference to the imaginal prototype with the exception of photographs rated highest in self-reference. Females were reliably superior to males in self-recognition. Males and females also differed in nonverbal behaviors reflecting differences in their image of real self. Results were interpreted as supporting an hypothesis that the self functions as a cognitive prototype which has both imaginal and verbal characteristics.     

The relationship between father absence and children's social problem solving competencies

Predictions of deficits in children's social problem-solving competencies due to early and continuing father absence were investigated. To test these predictions, equal numbers of father-present and father-absent third graders matched on a number of variables were assessed on measures of social problem-solving performance. In Phase 2 of the study, half of the children from the father-absent category received a 15 week intervention programme which was conducted by adult male trainers to provide structured practice in social problem solving. Results demonstrated that father-absent treatment subjects, compared to father-absent control subjects, improved their social problem-solving skills significantly. Despite improvement due to intervention, social problem-solving scores for father-absent treatment subjects were still below those for father-present control subjects. Educational and developmental implications of the findings were discussed.