The role of dopamine in reinforcement: changes in reinforcement sensitivity induced by D1-type, D2-type, and nonselective dopamine receptor agonists

Dose-dependent changes in sensitivity to reinforcement were found when rats were treated with low, moderate, and high doses of the partial dopamine D1-type receptor agonist SKF38393 and with the nonselective dopamine agonist apomorphine, but did not change when rats were treated with similar doses of the selective dopamine D2-type receptor agonist quinpirole. Estimates of bias did not differ significantly across exposure to SKF38393 or quinpirole, but did change significantly at the high dose of apomorphine. Estimates of goodness of fit (r2) did not change significantly during quinpirole exposure. Poor goodness of fit was obtained for the high doses of SKF38393 and apomorphine. Decrements in absolute rates of responding were observed at the high dose of quinpirole and at the moderate and high doses of SKF38393 and apomorphine. Changes in r2 and absolute responding may be due to increases in stereotyped behavior during SKF38393 and apomorphine exposure that, in contrast to quinpirole, were distant from the response lever. The present data provide evidence that sensitivity to reward is affected more strongly by dopamine D1-like receptors rather than D2-like receptors, consistent with evidence from other studies investigating consummatory dopamine behavior and the tonic/phasic dopamine hypothesis.     

Parent and Child Anxiety Sensitivity: Relationship in a Nonclinical Sample

Little is known about the relationship between parent and child anxiety sensitivity (AS), particularly in nonclinical samples. The present study examined this association in 207 healthy parent-child pairs including 244 children (mean age = 12.3 years, 103 girls) and 226 parent figures (175 mothers). Sequential multiple linear regression revealed that parent AS was significantly associated with child AS in girls, but not in boys. Parent AS accounted for 9% of incremental variance in child AS, after controlling for child age, parent depression, and parent anxiety. Analyses of parent AS dimensions indicated that the social concerns dimension accounted for 14% of incremental variance in child AS in girls only. Parent anxiety and depression showed no association with child AS, once parent AS was taken into account. The findings indicate that parent AS, especially AS social concerns, demonstrates a significant relationship with child AS in this nonclinical sample of girls.     

Stereotype Threat in Men on a Test of Social Sensitivity

This study provides evidence of stereotype threat in men on a test of a feminine ability called social sensitivity, that is, the ability to decode nonverbal cues. Men who were told that the test assessed social sensitivity and produced better scores for women than men performed worse on the test than did men who were told that the test assessed information processing. Because social sensitivity can be an automatic skill and stereotype threat uses mental capacity, this effect was moderated by self-reported strategy usage. Mens performance worsened in the threat condition only when they reported more deliberative and less intuitive strategies for decoding nonverbal cues.     

A cross-sectional evaluation of the factorial invariance of anxiety sensitivity in adolescents and young adults

This study examined the cross-sectional factorial invariance of anxiety sensitivity in an ethnically diverse sample of adolescents (n = 173; mean age 15.5 years) and young adults (n = 291; mean age 20.1 years). Research in adult and youth samples suggests that anxiety sensitivity is best understood as a hierarchical construct with several lower-order factors. Factor models based on previous research using both adult and youth samples were compared and a hierarchical model with three lower-order factors provided the best fit to the data. Results supported the hypothesis that the factor structure of the Anxiety Sensitivity Index was invariant across age and gender. The factor scores also demonstrated differential correlations with symptoms of anxiety and depression. Results are discussed with regard to construct validation and understanding the structure of anxiety sensitivity in youth.     

Training Family Therapists in a Multicultural Setting

Authors describe a multicultural training model for family therapists and psychologists at a traditionally conservative Afrikaans speaking university in South Africa. Black psychologists are now receiving high priority in a masters degree program that leads to professional registration licensure because of the needs of the population. The authors emphasize the importance of being able to think multidimensionally and creating a context in which students can do the same in such contexts.     

The relation between the generalized matching law and signal-detection theory

The generalized matching law can be applied to a signal-detection matrix to give two equations. The first relates responding in the presence of the stimulus to the reinforcements for the responses, and the second relates responding in the absence of the stimulus to the reinforcements for the responses. Evidence for stimulus discrimination is given by biases that are opposite in sign in the two equations. As the logarithmic ratio and z proportion transformations are similar, the combination of the absolute values of the two logarithmic biases gives a measure equivalent to the signal-detection measures d′ and η. The two equations can also be combined to eliminate the biases caused by the signalling stimuli and to produce a generalized matching-law statement relating overall performance to the obtained reinforcements.     

Statistical inference based on ranks

This paper develops a unified approach, based on ranks, to the statistical analysis of data arising from complex experimental designs. In this way we answer a major objection to the use of rank procedures as a major methodology in data analysis. We show that the rank procedures, including testing, estimation and multiple comparisons, are generated in a natural way from a robust measure of scale. The rank methods closely parallel the familiar methods of least squares, so that estimates and tests have natural interpretations.This research was supported in part by grant MCS76-07292 from the National Science Foundation.     

Verbal self-reports about matching to sample: effects of the number of elements in a compound sample stimulus.

Adults' self-reports about their choices in a delayed matching-to-sample task were studied as a function of the number of elements (one, two, or three) in a compound sample stimulus. Signal-detection analyses were used to examine control of self-reports by the number of sample elements, by the speed and accuracy of choices reported about, and by several events contingent on self-reports. On each matching-to-sample trial, a sample element appeared as one of two comparison stimuli. Choice of the matching element, if made within 500 ms of the onset of the comparison stimuli, produced points worth money or chances in a drawing for money, depending on the subject. After each choice, subjects pressed either a "yes" or "no" button to answer a computer-generated query about whether the choice met the point contingency. The number of sample elements in the matching-to-sample task varied across trials, and events contingent on self-reports varied across experimental conditions. In Experiment 1, the conditions were defined by different combinations of feedback messages and point consequences contingent on self-reports, but self-reports were systematically influenced only by the sample-stimulus manipulation. Self-report errors increased with the number of sample elements. False alarms (inaccurate reports of success) were far more common than misses (inaccurate reports of failure), and false alarms were especially likely after choices that were correct but too slow to meet the point contingency. Sensitivity (A') of self-reports decreases as the number of sample elements increased. In addition, self-reports were more sensitive to choice accuracy than to choice speed. All subjects showed a pronounced bias (B'H) for reporting successful responses, although the bias was reduced as the number of sample elements increased and successful choices became less frequent. Experiment 2 demonstrated that the failure of point contingencies to influence self-reports in the first experiment was not due to a general ineffectiveness of the point consequences. Rates of inaccurate self-reports decreased when they resulted in point losses and increased when they resulted in point gains.     

Infant–mother social referencing interactions: Description and antecedents in maternal sensitivity and infant irritability

The purpose of the study was to describe naturally occurring infant and maternal behaviours in terms of social referencing in a stranger wariness situation, and to explore antecedents to such behaviouts in early maternal sensitivity and infant irritability. One hundred and ten 10-months-old infants and their mothers were videotaped. Infant social referencing behaviour was defined as puzzled looks directed at mother's face after the infant had discovered the stranger. Almost half of the infants looked with a puzzled expression at their mothers immediately after discovering the stranger, and a majority of the mothers sent a positive message back to the infants. Twenty per cent of the infants never looked at their mothers and 20% of the mothers did not respond when their infants turned to them. Infants whose mothers had responded positively to the referencing look showed positive responses to the stranger to a higher degree than infants who did not reference or those who were not responded to. Antecedents to infant and mother interactive behaviours were sought in maternal sensitivity (general sensitivity, physical contact, responsiveness, intrusiveness, response to distress, and effectiveness in comforting) and in infant irritability as observed when the infants were 4 months old. It was found that infants who did not reference their mothers for information at 10 months had experienced less sensitive mothering 6 months earlier and had also shown more irritability.     

Transient effects of acquisition history on generalization in a matching-to-sample task

This study examined the role of learning history on the acquisition of a matching-to-sample task. Twelve preschool children learned four stimulus classes through instructions, shaping, or imitation. After reaching criterion, the subjects were exposed to changed discrimination contingencies to determine how each learning history affected the acquisition of responses appropriate to the new contingencies. All subjects reached criterion on the new relations, although the subjects with a shaping history adapted slightly more quickly than those subjects with a history of instructions or imitation. Given sufficient exposure to changed contingencies, rule-driven insensitivity to contingencies was overcome by experience with consequences. This result may be specific to younger subjects, but it suggests that instructions can be used in education without creating insensitivity to contingencies.