Double response to Stroop stimuli.

To reexamine Klein's 1964 findings we carried out two experiments on the double response made to Stroop stimuli. In Exp. 1 incongruent color-word stimuli were presented on a CRT online with a microcomputer. A color-word card was used in Exp. 2. Subjects were asked to read words before naming colors or, conversely, to name colors before reading words. An analysis of variance (the task x the type of task) was performed on response times in both experiments. Two main effects and interactions were nonsignificant. Some subjects made an error-like reverse-order response on the double-response task. The present findings do not support Klein's findings or the competition explanation of the Stroop effect.     

Amnesic effect of cycloheximide in the mouse mediated by adrenocortical hormones.

The involvement of adrenocortical hormones in the amnesic effect of cycloheximide was examined in mice. Subcutaneous injection of cycloheximide shortly before a training trial of a passive avoidance task resulted in an amnesia of the avoidance response. However, amnesia was absent in the adrenalectomized animals in which cerebral protein synthesis was suppressed by cycloheximide. Injection of corticosteroids antagonized the amnesic effect, most effecively if the steroids were given immediately after training. The influence of the hormonal treatments upon the amnesic effect was not ascribable to a change in general activity level. The amnesic effect of subcutaneously injected cycloheximide appears to be mediated by hormonal deficiency, and not related to suppression of the cerebral protein synthesis.     

Removal of an obstacle: Problem-solving behavior in pigeons

The importance of a subject's personal history in the solution of an obstruction problem was demonstrated with pigeons. Four birds were trained to peck a key located outside the chamber by poking their heads through an opening in a screen. During tests, a white block was placed in front of the opening, so that it was not possible to peck the key without removing the block. All birds failed to remove the block. However, all birds that were subsequently trained to push the white block around the chamber in the absence of the key and a few of the birds trained similarly but with a black block solved the problem by pushing the block aside and pecking the key. One bird showed the abrupt descent in the learning curve that has been considered a characteristic of “insightful” problem solving. All birds maintained their successful performance after a 1-month interval with no intervening tests.     

Autokinetic movement and inverted vision

It was considered that inverted vision could influence the condition of the subject's relative framework. The aim of this study was to investigate whether autokinetic movement observed during inverted vision might differ from that in normal vision. One subject wearing inverting spectacles and another one subject in normal vision observed autokinetic movement for five days. The results showed that directional changes increased with the time spent in visual inversion, while in normal vision such tendency was not observed. One speculative interpretation was suggested in terms of subject-related framework.     

Renewal of operant performance formerly eliminated by omission or noncontingency training upon return to the acquisition context

Renewal of operant performance formerly eliminated by omission or noncontingency training was explored in two experiments with rats. When pressing a lever was trained with food reinforcement in one context (A) and then eliminated in a second context (B), responding was renewed by returning the rats to the original context (A). This ABA renewal effect was demonstrated in Experiment 1 when the elimination training was an omission procedure (delivery of food for withholding responding) and in Experiment 2 when it was a noncontingency procedure (delivery of food irrespective of responding). Because omission training (differential reinforcement of other behavior) and noncontingency training have been used in applied settings as effective procedures to reduce undesired human behaviors, the clinical implications of our findings for the relapse of undesirable behavior were discussed.     

Differential outcome effect in the horse

Three horses were trained with a discrimination task in which the color (blue or yellow) of a center panel signaled the correct (left or right) response (lever press). Reinforcing outcomes for the two correct color-position combinations (blue-left and yellow-right) were varied across phases. Discrimination performance was better when the combinations were differentially reinforced by two types of food (chopped carrot pieces and a solid food pellet) than when the combinations were randomly reinforced by these outcomes or when there was a common reinforcer for each of the correct combinations. However, the discrimination performance established by the differential outcome procedure was still 80% to 90% correct, and an analysis of two-trial sequences revealed that the stimulus color of the preceding trial interfered with discrimination performance on a given trial. Our demonstration of the differential outcome effect in the horse and its further analysis might contribute to more efficient control of equine behavior in the laboratory as well as in horse sports.     

Cross-cultural Protective Effects of Neighborhood Collective Efficacy on Antisocial Behaviors: Mediating Role of Social Information Processing

Studies on the prevention of antisocial behavior in neighborhoods through efficacious social control have focused on collective efficacy as the theoretical mechanism by which children at the community level can be successfully socialized to develop an aversion to antisocial behaviors. We hypothesized that the effect of collective efficacy within communities on antisocial behaviors could be mediated by social-information-processing biases and tested the generality of these mediation effects for undergraduates (N = 929) in Japan, China, South Korea, and the United States, countries with widely varying cultures and political systems. Structural equation modeling revealed that the effects of collective efficacy on antisocial behaviors were perfectly mediated by social-information-processing biases. Findings also confirmed the generality of these mediational effects in all four countries investigated.     

Gender gaps in cognitive and social‐emotional skills in early primary grades: Evidence from rural Indonesia

This paper examines the magnitude and source of gender gaps in cognitive and social‐emotional skills in early primary grades in rural Indonesia. Relative to boys, girls score more than 0.17 SD higher in tests of language and mathematics (cognitive skills) and between 0.18 and 0.27 SD higher in measures of social competence and emotional maturity (social‐emotional skills). We use Oaxaca–Blinder decomposition to investigate the extent to which gender differences in early schooling and parenting practices explain these gender gaps in skills. For cognitive skills, differences in early schooling between boys and girls explain between 9% and 11% of the gender gap whereas differences in parenting practices explain merely 3%–5% of the gender gap. This decomposition result is driven largely by children living in villages with high‐quality preschools. In contrast, for social‐emotional skills, differences in parenting styles toward boys and girls explain between 13% and 17% of the gender gap, while differences in early schooling explain only 0%–6% of the gender gap.     

Functional magnetic resonance imaging of human cognitive processes

Functional magnetic resonance imaging (fMRI) is now widely accepted as a tool for analyzing human brain function. Since the realization of fMRI in the early 1990s, numerous reports have been published. In this paper, we present three studies. The first examined syntactic processing of Japanese sentences and the results prove that Broca's area is involved in the use of grammar. The second study compared binocular with monocular stereopsis. There were significant activations in the right inferior parietal lobe. The third study concerned the encoding and retrieval processes underlying face recognition. It revealed activations mainly in the right prefrontal areas, which is contrary to the hemispheric encoding and retrieval asymmetry (HERA) theory. fMRI will continue to play an important role in the analysis of human brain function.