Intergroup fairness and bias in children

In recent years in research on intergroup relationships, the assumption has increasingly been made that discrimination dominates decisions when individuals allocate resources between (members of) own and other group. Conversely, in empirical studies of interpersonal decision-making, including an extensive literature on the development of children's allocation rules within dyadic relationships, it has been repeatedly observed that in dyadic relationships choices though responsive to various changes in the environment, are more strongly governed by fairness rules. The present research extends the interpersonal fairness paradigm to the intergroup case, and examines the effects of some of those variables, namely, children's age, input and attitudes toward other, that have been observed to influence choice behaviour within interpersonal relationships. The findings indicate that as children are socialized, fairness rules also play an increasing dominant role in intergroup allocation decisions, and that both relative input and the language of the outgroup influence such decisions. At the same time, there is some preliminary evidence to indicate that the relative strength of self-interest may be somewhat stronger in intergroup than in interpersonal relationships. Finally, a number of the issues that must be confronted in comparing the two more important forms of human social choices, interpersonal and intergroup decision-making, are considered.     

Processing resources and age differences in working memory

This study investigated the performance of young and old subjects on a modified version of the working memory task developed by Baddeley and Hitch (1974). Subjects were required to verify a set of sentences of varying complexity while they repeated aloud zero, two, or four words. The older subjects took longer to verify the sentences, especially when the sentences were grammatically complex, but the effect of concurrent memory load on verification latency was the same in both groups. These results cast doubt on the notion that there is an age-related decline in one general pool of processing resources. They also suggest that older people have greater difficulty with the active processing aspects, rather than with the passive holding aspects, of working memory tasks.     

Hindsight bias: An interaction of automatic and motivational factors?

If subjects are asked to recollect a former response after having been informed about the correct response, their recollection tends to approach the correct response. This effect has been termedhindsight bias. We studied hindsight bias in an experiment requiring numerical responses to almanac-type questions for physical quantities. We varied (1) the time at which the correct information was provided, (2) the encoding of the original responses by asking/not asking subjects to give a reason for the respective response, and (3) the motivation to recall correctly. We found that hindsight is less biased if reasons are given and if the correct information is provided at an earlier time. Motivation had only interactive effects: (1) With high motivation to recall correctly, the time the correct information was provided had no influence. (2) With reasons given, the variation of motivation showed no effect. These results rule out purely motivational and purely automatic explanations.     

A comparison of alternative theoretical approaches to smoking cessation and relapse

Two theoretical approaches to smoking cessation were compared. Participants were randomly assigned either to (a) a traditional treatment program that used contingency contracting and that emphasized the necessity for absolute abstinence (AA) or to (b) a relapse-prevention (RP) treatment that focused on gradual acquisition of nonsmoking skills. It was hypothesized that participants in the RP treatment would be less successful initially but would have better maintenance skills and thus would relapse less during a 1-year follow-up period. Each program was evaluated in two formats: group-based treatment and self-help materials. Results indicated comparable 1-year abstinence rates for all treatments, although more participants dropped out of the self-help formats. Participants in the RP intervention were more likely to lapse sooner after quitting and were more likely to quit again during the 1-year maintenance period. Exploratory analyses of successful participants suggested that women were more successful in the RP program and that men had greater success with the AA approach.     

The discrimination of human odour by the dog

In reply to a suggestion made by Galton in 1875, the ability of dogs to discriminate between the odour of human twins was investigated. In a matching-to-sample simultaneous discrimination task, dogs were tested on their ability to discriminate odours from twins differing only in genetic relatedness or only in environmental factors, particularly diet, or from twins identical in both genetic relatedness and environmental factors. Dogs could discriminate between the odours from twins who differed only in environmental factors and between the odours of twins who differed only in genetic relatedness. However, they were unable to discriminate between odours produced by infant twins identical in both genetic relatedness and environmental factors. Thus twins may be discriminated by dogs as long as they differ in genetic relatedness or environmental factors. The possible source of discriminable odours is discussed and how the effects of genes and environment are mediated considered.     

The perception of an optical flow projected on the ground surface

In most experiments in which the importance of visual control on postural stability is studied, optical stimuli attached to vertical surfaces are used. Analyses of long-term standing readjustments generally involve back-and-forth movements of a visual scene or its projection on vertical circular screens. In a natural environment, however, visual information is largely available from the ground. The aim of the experiment reported was to assess the effect of a flow pattern simulating an open outdoor setting on motion perception and postural control. Subjects were presented with an optical texture projected onto the ground. Periods of motionless texture alternated with equivalent durations of unidirectional flows. The change of position of the subject's centre of gravity over time was recorded on a force platform. Results show that the direction of body sway corresponded with that of texture motion. Important aftereffects, as shown in linear vection experiments, were also observed. However, the latency of postural responses was much shorter than with prolonged unidirectional flows produced in other locations of the visual environment. The hypothesis of an ecological specificity of the flows perceived on the ground during terrestrial displacements is discussed.     

Association between anxiety and depression in children and adolescents with anxiety disorders

The relationship between anxiety and depression was examined in a sample of 106 children and adolescents referred to an outpatient anxiety disorder clinic for children. Twenty-eight percent of patients with DSM-III diagnoses of anxiety disorders displayed a concurrent major depression. Children with anxiety disorders plus major depression were found (1) to be older, (2) to demonstrate more severe anxiety symptomatology, and (3) to be diagnosed with different rates of certain anxiety-disorder subtypes, when compared to anxious patients without major depression. Nondepressed anxious children and adolescents did not differ from a psychopathological control group in severity of either anxiety or depression symptoms.     

Force variability in isometric responses

In the present study we examined the contribution of different impulse parameters to peak force variability in an isometric task. Five experiments are reported that each held constant a different impulse parameter while allowing the other impulse parameters to vary. The results indicate that change in force level is the parameter that has the greatest effect on peak force variability, although time to peak force and preload also systematically influence response variability. A formula that accommodates the relation between impulse parameters and force variability is proposed. The data suggest that even in isometric tasks, it is the force-time properties of the impulse, rather than discrete parameters such as peak force, that determine the outcome variability.