Showing-off behaviour of nursery children

Assertive behaviours like showing-off have an important role for a child in getting attention from other children in a class without being aggressive. This study presented the showing-off behaviour in an English nursery school, and later it was discussed in comparison with that in the German kindergartens reported by Hold-Cavell. As a result, the English children performed showing-off behaviours at only one-half the frequency of German children. No sex difference was seen in either showing-off or physical aggression in the nursery class. The frequency of showing-off did not correlate with that of physical aggression; this result is discussed in terms of Hinde's motivational postulate. Showing-off behaviour is deserving of the further studies cross-culturally and onto-genetically.     

D-cycloserine facilitates procedural learning but not declarative learning in healthy humans: a randomized controlled trial of the effect of D-cycloserine and valproic acid on overnight properties in the performance of non-emotional memory tasks

Although D-cycloserine (DCS), a partial agonist of the N-methyl-d-aspartate (NMDA) receptor, and valproic acid (VPA), a histone deacetylase inhibitor, have been investigated for their roles in the facilitation of emotional learning, the effects on non-emotional declarative and procedural learning have not been clarified. We performed a randomized, blind, placebo-controlled, 4-arm clinical trial to determine the effects of DCS and VPA on the overnight properties of declarative and procedural learning in 60 healthy adults. Subjects were orally administrated a placebo, 100 mg DCS, 400 mg VPA, or a combination of 100 mg DCS and 400 mg VPA before they performed declarative and procedural learning tasks. Subjects then had their performance retested the following day. We observed that DCS facilitated procedural but not declarative learning and that VPA did not contribute to learning. Surprisingly, however, VPA attenuated the enhancement effect of DCS when coadministered with it. These results suggest that DCS acts as an enhancer of hippocampus-independent learning and that VPA may have an extinguishing pharmacological effect on excitatory post-synaptic action potentials that NMDA receptors regulate within procedural learning.     

Task-dependent changes of the psychophysical motion-tuning functions in the course of perceptual learning

In some cases, perceptual learning is task-specific. However, task-dependent effects of perceptual learning on psychophysical motion-tuning functions have yet to be clarified. In the present study, subjects performed motion detection or discrimination of the same stimulus over the course of four sessions held on separate days. Subjects who performed motion detection showed the most highly improved performance on the trained motion directions. However, after discrimination training, the highest improvement was not observed at the trained directions but shifted away from them. These results can be explained by lateral inhibition. Task demands may differentially modulate excitatory and inhibitory signals to directions in the vicinity of the trained directions.     

Tensile properties of precracked tempered martensitic steel specimens tested at ultralow strain rates in high-pressure hydrogen atmosphere

Tensile tests were performed on precracked Cr–Mo martensitic steel (C: 0.38, Si: 0.22, Mn: 0.84, P: 0.024, S: 0.021, Ni: 0.08, Cr: 1.11, Mo: 0.15, Cu: 0.12, Fe: bal. (wt%)) specimens at various strain rates (ranging from 6.5 × 10^?8 s^?1 to 1.0 × 10^?4 s^?1) in high-pressure (95 MPa) hydrogen and helium atmospheres. Irrespective of the strain rate, the tensile strength in the helium atmosphere was 1400 MPa. In the hydrogen atmosphere, the tensile strength decreased to less than 600 MPa at a strain rate of 2.0 × 10^?5 s^?1. However, the tensile strength increased to 900 MPa when the strain rate was decreased to 6.5 × 10^?8 s^?1. This recovery of the tensile strength was because of the decrease in the local stress in the vicinity of the precrack because of hydrogen.     

Alcohol Use,Acculturative Stress,and Drinking Motivation Among International Community College Students

Alcohol use, acculturative stress, and drinking motivations of 262 students in English as a second language programs in a U.S. community college were explored. Alcohol consumption was generally low, but differences between two groups with different legal statuses indicate the need to consider subgroups of international students for research purposes. Se exploraron el uso de alcohol, el estrés por aculturación y las motivaciones para beber de 262 alumnos en programas de inglés como lengua extranjera en una universidad comunitaria estadounidense. El consumo de alcohol fue moderadamente bajo, pero las diferencias entre dos grupos con diferente estatus legal indican la necesidad de considerar subgrupos de estudiantes internacionales a la hora de realizar investigaciones.     

Intermale aggression in rats selected for emotional reactivity and their reciprocal F1 and F2 hybrids

The aggressive behavior of two selectively bred rat strains (high “H” and low “L” emotional reactivity) and their reciprocal F1 and F2 hybrids were measured during three consecutive days in home-cage intruder tests. In terms of biting, bite latency, on-top-of and aggressive grooming, L males were more aggressive than H and F1 males. There was no difference between H and F1, nor between HLF1 and LHF1 with the exception that LHF1 showed more on-top-of. About one fourth of F2 males were equal to or more aggressive than L in terms of bite latency and number of bites. These findings suggest that aggressiveness was inherited as a recessive, monogenic trait in these rats.     

Effects of semantic context and event-related potentials: N400 correlates with inhibition effect

Two experiments investigated the modulation of event-related brain potentials (ERPs) by semantic context. A prime-target pair was visually presented in each trial of a lexical decision task. For word targets, three types of relatedness conditions were employed: (1) Related word condition (e.g., school-teacher); (2) Neutral word condition (e.g., [symbol: see text] - number); (3) Unrelated word c((e.g., hospital-potato). In Experiment 1, the reaction time for unrelated targets was longer than that for neutral targets (inhibition effect) which was longer than that for related targets (facilitation effect). The N400 amplitude in the unrelated targets was larger compared to those in the related and neutral targets, which did not differ. In Experiment 2, where only the facilitation effect was obtained, the N400 amplitude did not differ among conditions.     

TOWARD A MULTI-LEVEL,MULTI-STAGE MODEL OF MODERNIZATION A CROSS-CULTURAL SOCIAL-PSYCHOLOGY APPROACH1

Le développement économique est présenté comme un processus écologique impliquant des antécédents et conséquents à la fois institutionnels et psychologiques dont les interactions composent un modèle complexe. Sont étudiées plus particulièrement ici les variables psychologiques qui, dans une culture donnée, se révèlent susceptibles d'influencer le phénomène de modernisation. Les attitudes de divers groupes culturels envers certaines valeurs spécifiques ayant trait au développement économique sont mesurées par des différenciateurs sémantiques multilingues. Ces appréciations sont analysées et comparées en fonction du degré d'industrialisation des pays étudiés.