Category learning in the context of co-presented items

A series of four studies explore how the presentation of multiple items on each trial of a categorization task affects the course of category learning. In a three-category supervised classification task involving multi-dimensionally varying artificial organism-like stimuli, learners are shown a target plus two context items on every trial, with the context items’ category membership explicitly identified. These triads vary in whether one, two, or all three categories are represented. This presentation context can support within-category comparison and/or between-category contrast. The most successful learning occurs when all categories are represented in each trial. This pattern occurs across two different underlying category structures and across variations in learners’ prior knowledge of the relationship between the target and context items. These results appear to contrast with some other recent findings and make clear the potential importance of context-based inter-item evaluation in human category learning, which has implications for psychological theory and for real-world learning environments.     

Reference group data for the Reitan-Indiana Neuropsychological Test Battery for Young Children

This study presents a data set for a reference group on the Reitan-Indiana Neuropsychological Test Battery for Young Children. The data set is based on a sample of 224 children, ages 5 to 8 years, referred to a special services cooperative for academic or behavioral concerns during the years 1980 through 1993. Data are presented in terms of sample size, means, standard deviations, diagnostic classifications, and population characteristics. Previously published data sets are reviewed in comparison to this newly acquired data set. Potential advantages of this data set include the larger sample, contemporary data collection, and a sample drawn from a United States school-referred population.     

The localization over time of exogenous aldosterone and angiotensin II in various organs

Central nervous system effects have been demonstrated for angiotensin II and suggested for aldosterone. In order to determine whether either of these chemicals naturally crosses the blood-brain barrier, radioactive aldosterone and angiotensin II were introduced via intracardiac injections in rats. Samples of blood, liver, kidney, adrenals, cerebral cortex, and hypothalamus were collected at three, 15, and 60 minutes, frozen, dissolved, and counted. Blood levels for aldosterone and angiotensin II remained constant over 60 minutes. Aldosterone accumulated in the liver, kidney, adrenals and hypothalamus three minutes after injection, and levels diminished over time. Angiotensin II levels peaked in the adrenal, kidney, and liver after three minutes, and in the hypothalamus after 15 minutes. Cerebral cortex levels were lower than hypothalamic levels by 30% for aldosterone and 50% for angiotensin II. This suggests that both drugs may enter the central nervous system and selectively accumulate in the hypothalamus.     

Careers education and counselling in Northern Ireland: A historical outline

Vocational guidance services have been developing in Northern Ireland for about thirty years. Recently the careers service has been transferred from an education to a manpower services base, while the schools have been given greater opportunity, and responsibility, for the provision of careers education. The changes have given considerable impetus to careers teacher training, and to the appointment of schools' careers staffs. The possibility of further development of the partnership between careers officers and careers teachers is examined.     

The Effect of Anxiety on the Conditioning Rate and Stability of the PGR

Two separate experiments were completed to test the effect of valence on performance of kindergarten Ss on a conservation task. Forty-eight Ss in Experiment I, with a mean age of 5.5 years, were asked to conserve a volume of liquid. A significant number of Ss failed to conserve the volume (p < .001), but when valence—desirability of the liquid to drink—was added, a significant number of Ss changed their choices (p < .02) to show conservation. Thirty-eight Ss in Experiment II, with a mean age of 5.5 years, were asked to conserve volume of liquid with valence attached to the first choice. A significant (p < .01) number of Ss showed conservation of volume. The results of the two experiments were compared and discussed in relation to valence and language development as relevant variables in conservation tasks.     

Book Reviews

Book Reviews

Book Reviews