Conditioned defensive burying in rats: Availability of burying materials

Rats shocked once by a stationary, wire-wrapped prod mounted on the wall of the test chamber incorporated sand, wooden blocks, or commercial bedding material on the floor of the chamber into a defensive response. They moved the available material toward and over the shock prod in all three conditions, adapting the response topography to the particular demands of the available material. In the sand and bedding conditions, the rats buried the prod by pushing and spraying piles of the material with snout and forepaws, whereas, in the blocks condition they picked up the blocks with their teeth and placed them individually around the prod. In Experiment 2, the rats buried the shock prod with blocks even when they had to first carry the blocks to the prod from the back of the chamber. Thus, conditioned defensive burying is not a simple, reflexive response to objects paired with a painful stimulus: it is a complex behavioral sequence that can vary as a function of the availability of burying materials.     

Habituation and dishabituation of rats’ exploration of a novel environment

The habituation of locomotor activity across repeated exposures to a novel maze was studied in a series of experiments using rats as subjects. Habituation, defined as a decrease in ambulation, was greater on a second trial occurring 5 min after a first trial than on one occurring 60 min after. This short-term decrement occurred only when the same maze was used on both trials, and could be dishabituated by intertriai detention in another novel environment. On a delayed test trial, habituation was, in one case, somewhat greater following initial spaced trials, and in another condition, comparable following both massed and spaced trials. The longer term habituation was maze specific, but was not affected by the presence of a dishabituator following either or both of the first two trials. The results were discussed in terms of theories of “priming” and encoding variability.     

A cross-national survey of cultural expectations and sex-role standards in reading

Cultural expectations and sex-role standards about reading in Canada, Denmark, England, Finland, Israel, Japan, and U.S.A. were investigated. A picture test showing various activities and objects including reading and books was administered in each country to six sub-samples that approximated to the levels: students in grades I, IV, VIII, and XII, college students, and adults. Subjects had to ascribe the activity or object as being appropriate for either a boy or a girl. The results were consistent with the hypothesis that cultural expectations and sex-role standards about reading are congruent within one country but that they differ between countries. In particular, boys in Canada and the U.S.A. rapidly learn to perceive reading as a feminine activity, whereas Danish and Japanese males at all ages consistently view reading as acceptable masculine behaviour.     

Attachment behavior: a validation study in two age groups.

To assess the validity of attachment scores derived from the Ainsworth "strange situation," 56 1-year-olds and 79 2-year-olds accompanied by either the mother, the father, or a brief acquaintance were studied. Proximity to the adult, duration of play, crying, activity, and the incidence of looks and distance bids were measured. 1-year-olds were more secure with their parents: they were more active, played more, cried less, and stood closer to their parents than to an acquaintance. 2-year-olds accompanied by their parents were less settled in the presence of a stranger than children accompanied by the acquaintance. The adequacy of current conceptions and measures of attachment was discussed in light of these results.     

Dimensional salience and judgments of bigness by three-year-old children.

3-year-olds were shown triads of rectangles and asked to select the "big" one, where the biggest rectangle in each triad was neither the tallest nor the widest. Dimensional salience and response choice were highly related. In addition, as saliency of a particular dimension increased relative to the other dimension, significantly more responses were based on that dimension. The results support the notion that the young child does not rely on 1 specific dimension to make judgments of bigness but, rather, attends to the most salient differences among stimuli.