Categorical shape and color coding by pigeons

Categorical coding is the tendency to respond similarly to discriminated stimuli. Past research indicates that pigeons can categorize colors according to at least three spectral regions. Two present experiments assessed the categorical coding of shapes and the existence of a higher order color category (all colors). Pigeons were trained on two independent tasks (matching-to-sample, and oddity-from-sample). One task involved red and a plus sign, the other a circle and green. On test trials one of the two comparison stimuli from one task was replaced by one of the stimuli from the other task. Differential performance based on which of the two stimuli from the other task was introduced suggested categorical coding rules. In Experiment 1 evidence for the categorical coding of sample shapes was found. Categorical color coding was also found; however, it was the comparison stimuli rather than the samples that were categorically coded. Experiment 2 replicated the categorical shape sample effect and ruled out the possibility that the particular colors used were responsible for the categorical coding of comparison stimuli. Overall, the results indicate that pigeons can develop categorical rules involving shapes and colors and that the color categories can be hierarchical.     

Sex differences in the effects of gonadectomy on amphetamine-induced rotational behavior in rats

The effects of gonadectomy on amphetamine-induced rotational behavior were studied in male and female rats. Different systemic doses were used to produce equivalent brain concentrations of the drug in each group, thereby controlling for sex differences in the metabolism of amphetamine. Ovariectomy of female rats significantly attenuated amphetamine-induced rotation, whereas castration of males was without effect. The results support the idea that in females, the endogenous gonadal hormones facilitate functional activity in the mesostriatal dopamine system.     

Glucose modulation of memory storage processing

Epinephrine, derived from the adrenal medulla, enhances memory storage for several forms of learning. One physiological action of this hormone is to liberate hepatic glucose stores. This experiment tested the possibility that glucose could itself enhance memory. Rats were water deprived, pretrained to drink, pretrained to drink in the behavioral apparatus, and then trained in a one-trial inhibitory (passive) avoidance task. Immediately after the training footshock, the animals each received an injection of glucose (1.0-500 mg/kg). When tested for retention 24 h later, the animals which received 10 or 100 mg/kg doses of glucose exhibited enhanced retention performance; higher and lower doses had no significant effect on the memory tests. Also, glucose injections (100 mg/kg) delayed by 1 h after training had no effect on the retention tests. These findings suggest that the increase in plasma glucose levels subsequent to epinephrine injection may contribute to the effects of epinephrine on memory. In addition, the results suggest that peripheral glucose levels may exert important influences on memory storage.     

Incidental learning,distraction, and sustained attention in hyperactive and control subjects

Thirty-two children designated as hyperactive (ADD) were compared with an equal number of control subjects who were matched for age, sex, and verbal IQ. The subjects were tested on (1) a component selection task, measuring serial memory and incidental learning and (2) a cancellation task, assessing attentional variables and distractibility. No straightforward group differences were found on the component selection task, whereas hyperactive subjects made more omission and commission errors than controls on the cancellation task. It was concluded that a deficit in sustained attention and impulsivity best described the group differences. Age was also found to influence performance on a number of variables, including incidental learning on the component selection task and response rate and omission errors on the cancellation task. Because subjects in the hyperactive group were rated as extreme on a number of subscales not necessarily related to hyperactivity, the data were reexamined by multiple regression analyses. Subscales considered to be related both to hyperactivity and to conduct disorder were associated with different performance variables, indicating that each of these subscales provided some unique information.This study was supported by a grant from the Medical Research Council of New Zeland to the first author. The authors would like to thank the pupils and staff of Mt. Eden Normal Primary School and Newmarket School for taking part in the study, and the Auckland Education Board for granting approval for the study. We also thank Prof. J. S. Werry, Dr. J. Reeves, and Mrs. G. Elkind for assistance in locating some of the control subjects. Special thanks goes to Gail Elkind for assistance with the statistical analysis.     

Assessing depression in community samples of children using self-report inventories: Ethical considerations

Although the methodological problems associated with the use of children's self-report depression inventories have previously been discussed in detail, the ethical problems related to the use of these instruments have been largely ignored. The primary purpose of this survey study was to determine how childhood depression researchers have prepared for and responded to children from community (i.e., nonclinic) samples whose nonanonymous scores on self-report depression inventories have indicated that they might be severely depressed or suicidal. Several recommendations, based upon (a) the results of this survey study, (b) the existing literature relevant to the ethical responsibilities of investigators who conduct research with children, and (c) our own experiences with these instruments and populations, are made to assist researchers in their attempts to use these inventories in an ethical manner.The authors would like to thank those childhood depression researchers who were kind enough to return completed surveys.     

Health as a value: methodological and theoretical considerations

The concept of value placed on health is very important in several different theoretical approaches to the study of health behavior. In practice, however, health value is generally assumed to be universally high rather than being directly measured. If this assumption is incorrect, then theories that include health value have rarely been adequately tested. This paper presents a short 4-item Likert scale designed to measure the value placed on health. Norms from the utilization of this scale in five different samples are presented. Health value is found to increase with age among girls, but the increase apparently stops by late adolescence, before full adult levels of health value are achieved. Middle-aged women place a higher value on health than do middle-aged men, although no comparable sex difference appears in a sample of undergraduates. Consistent with theoretical predictions, both health locus of control beliefs and beliefs in the efficacy of certain preventive health behaviors correlate more highly with the performance of those same behaviors 5 to 9 months later among respondents who place a high value of health relative to those who do not value health so highly. However, this interaction is found only when it can be safely assumed that health is the primary value underlying the behavior. The importance of considering a variety of values in addition to health as possible motivators of preventive health behavior is stressed.     

The three-factor structure of the Eysenck personality inventory revealed by a two-step confirmatory procedure

Evidence for the existence of the assumed three-subscale structure of the Eysenck Personality Inventory has been persistent but tenuous. It was suggested that a substantial reason for this may be the discrepancy between the numbers of items in the Lie (L) scale (9 items) and those in the other two scales [Neuroticism (N) and Extraversion (E)] which have 24 items in each. A two-step confirmatory procedure to circumvent this problem was proposed, involving a two-factor analysis of the Neuroticism and Extraversion items, followed by a three-factor analysis of equal numbers of N, E and L scale items. An analysis of the responses of 386 undergraduates demonstrating the proposed procedure revealed in the first step, quite unequivocally, the presence of Neuroticism and Extraversion factors, and in the second step, a third factor clearly congruent with the L scale.     

Counseling Clients with AIDS

The authors discuss issues and suggestions relative to counseling clients with AIDS. Several psychosocial issues are presented, and a psycho-educational model of treatment to meet the needs of AIDS clients is described.     

A Comparison of Two Cases of Counseling with the Same Counselor

Process analyses revealed that interpretations and exploration of feelings were helpful across two cases. Other interventions were helpful for one case but not the other.