This study examined the information processing of categorizing line-drawn pictures by preschool (6-year-old) children, using a unique version of a Stroop-like picture-picture categorizing task which was used by Tazume (1999). In this task the participants were divided into two groups: a key press reaction group and a verbal reaction group. They were required to respond with the category of the target pictures (animal or fruit) and ignore the distracting pictures. To clarify the effect of semantic relations on the amount of interference, the following combinations of target and distracting pictures were presented: same stimulus (SS), same category (SC), different category (DC), neutral (N), and control (C). To investigate the time course of processing, the stimulus onset asynchrony (SOA) between the target and distractor was varied. The results indicated a Stroop-like interference effect in both groups. But the difference between the key press group and verbal reaction group was smaller than that of adults, and both were close to the verbal reaction of adults. These results seem to indicate that the ability of children to select the most effective processing route, according to task demand, is more limited than that of adults.
The memories of plans for the future must be represented in their order in time. In the present experiment, the possible effects of differences in retrieval style on the retrieval from memory of future plans were examined. Thirty-six undergraduates students participated and were asked to memorize 15 plans for one day. Each plan consisted of a 'time' and an 'action' phrase. The cued recall test had three different conditions: 'presentation', 'ascending', and 'descending'. In the 'presentation' condition each cue (the time of day) was presented in the same order as that of encoding (i.e., random for the time of day). In the 'ascending' condition each cue was presented according to its sequence in time. However, in the 'descending' condition each cue was presented in a reversed time sequence. The results showed that performance was best when plans were recalled in the 'ascending' condition. This suggests a 'looking-into-the-future' effect, i.e., a superiority of the retrieval of future plans according to their sequence in time.
This study investigated the effect of sodium hunger on sodium aversion learning in rats. The animals were exposed to either to a 0.1 M, 0.2M, or 0.3M sodium chloride solution prior to poisoning in a sodium-deprived or non-deprived state. Taste aversion was assessed by measuring the intake of a 0.2 M sodium chloride solution during a non-deprived state. The test indicated that sodium hunger increased aversion, and that the aversion was a positive function of the sodium concentration used in the learning phase. These results suggest that a sodium hunger increases the intensity of the perception of a salty taste.
This study examined the effect of reinforcer devaluation on within-session response decreases. After 16 rats were trained to press a lever for food pellets, pellets flavored with either cinnamon or cocoa powder were associated with lithium chloride. The rats' responses were then reinforced by one flavor of the pellets during 45-minute sessions in a continuous reinforcement (CRF) schedule for 8 days. The pellet flavor was alternated daily. At the start of the session the response rates were decreased by the taste-aversion learning. However, the manipulation did not alter the rate of the response decrease. The response rates were described by a linear function of the cumulative number of food pellets consumed within sessions. Reinforcer devaluation systematically altered the x- and y-axis intercepts but did not alter the slopes of the regression lines. These results suggest that taste-aversion learning lowered the initial response rate (y-axis intercept), but did not alter the rate of the response decrease produced by the food pellets consumed (slope), thereby reducing the cumulative number of pellets that would reduce the response rate to zero (x-axis intercept). These findings also revealed that the effects of the reinforcer devaluation on the parameters of the regression lines could be dissociated from the hunger attenuation reported elsewhere (Aoyama, 2000).
Two free recall experiments were performed with four emotional conditions. The subjects were given a central and incidental learning task with twenty pairs of emotional words. During the task the subjects studied one word of each pair with their attention focused (central learning) and the other with their attention divided (incidental learning). The central stimuli were underlined. The four conditions were manipulated by the type of emotional word pairs (negative-negative, negative-neutral, neutral-negative, neutral-neutral). During the incidental learning, the recall performance of the subjects was better with negative stimuli than with neutral stimuli. However, during central learning, a difference in their recall performance with these two types of stimuli was not observed. It is suggested that the facilitative effect on memory which was observed in the negative stimulus condition could be related to incidental and automatic attention, but not to selective and conscious attention.
Our COE program aims at creating new research field concerning verbal communication through multidisciplinary approach with researchers from various research fields including linguistics, cognitive neuroscience, cognitive psychology, and information science. Based on evolutionary perspective, my contribution to this program is to elucidate the relationship between cognition and emotion in verbal communication.
This paper outlines the Hokkaido University 21^<st> Century "Center for the Study of Cultural and Ecological Foundations of the Mind". While sharing a research focus on the "fundamental sociality" of the human mind with other top institutions around the world, our center is unique in emphasizing the mutual construction of mind and society, something we call micro-macro dynamics. We view the human mind as a toolbox that contains adaptive tools useful in solving social adaptation tasks. The social environment that engenders social adaptation tasks for our mind to solve, on the other hand, is our creation. Answering the question of how we collectively create and maintain the social environment that in turn provides incentives for us to develop a particular set of psychological tools is the unique goal of our Center.
As the COE program, we are now planning to organize a whole life development research center, which covers the development as a time-axis from "birth" to "death". The purpose of this center is as follows: 1) to conduct empirical studies investigating basic mechanisms of human development from indiviuai-enviornment transactionai point of view; 2) to clarify current condition of life events (e.g., entrance to school, getting a job, marriage, childbirth, retirement) and to explore psychological, social, cultural risk factors which interrupt successful developmental transitions. To achieve this purpose, several longitudinal studies (e.g., from birth to entrance to elementary school, from school to workplace, from middle-age to senescence) have been started and collection of data on life-span human development has begun.
The first half of this paper briefly introduces Center of Excellence for Psychological Studies awarded to Kyoto University as a project supported by the 21st Century COE Program from the MEXT. This project aims at comprehensive understanding of mental functions by integrating experimental, field, and clinical approaches to mind. With the goal set at "knowing mind and fostering mind", we aim to solve social problems invited by the highly information-oriented and aging society of the present days. The second half discusses what psychological science should tackle in this new century. Minds are evolutionary products installed in animate beings and thus are diverse just like other adaptive physical characteristics are. Minds are diverse among species, developmental stages, cultures, and even pathological statuses. Investigating all the possible forms of diverse minds is suggested to be essential in understanding minds as a whole.
COE project titled "Toward construction of an integrated method for understanding of mind" has started in 2002 at Keio University. The project consists of five teams and one of them is a team of evolutionary and developmental study of mind. Here I discussed a role of experimental psychology in this project. First of all, I separated two senses of mind, namely mind in the narrow sense (MNS) and mind in the broad sense (MBS). The former is object of the experimental psychology and the latter object of sciences concerning mental activities of human beings. Expected role of the experimental psychologists is bridging MNS and MBS. We employed two approaches. One is measurement of brain activity by NIRS from humans. The other is comparison of human cognition with animal cognition. During the next two years, we will start integrated researches, such as an integrated research of inference and an integrated research of beauty, as a joint research with several different teams. Finally, we intended to construct a method for understanding both of MNS and MBS.