Tufted capuchin monkeys (<Emphasis Type="Italic">Cebus apella</Emphasis>) show understanding of human attentional states when requesting food held by a human

Researchers have investigated to what extent non-human primates understand others’ attentional states, as this ability is considered an important prerequisite for theory of mind. However, previous studies using food requesting tasks have failed to show that non-human primates attribute perception to others as a function of their attentional states. One possible reason is that food requesting tasks may require subjects not only to take into account an experimenter’s attentional state but also to direct it toward the food. The present study tested tufted capuchin monkeys’ (Cebus apella) understanding of others’ attentional states in a food requesting task. In the first situation, monkeys were required only to attract an experimenter’s attention. In the second situation, the monkeys were required to both attract the experimenter’s attention and direct it toward food on a table. The results revealed that capuchin monkeys showed evidence of understanding the experimenter’s attentional variations only in the former condition. This suggests that previous tasks, requiring referential gestures, lacking in most non-human primates, failed to reveal sensitivity to human attentional states because the subjects might not have understood the requesting situation. In conclusion, capuchin monkeys can understand variations in others’ attentional states, although this ability appears limited compared to what is seen in humans.     

Item–trait association, scale multidimensionality, and differential item functioning identification in personality assessment

This report documents relationships between differential item functioning (DIF) identification and: (1) item–trait association, and (2) scale multidimensionality in personality assessment. Applying [Zumbo, B. D. (1999). A handbook on the theory and methods of differential item functioning (DIF): Logistic regression modeling as a unitary framework for binary and Likert-type (ordinal) item scores. Ottawa, ON: Directorate of Human Resources Research and Evaluation, Department of National Defense.] logistic regression model, DIF effect size is found to become increasingly inflated as investigated item associations with trait scores decrease. Similar patterns were noted for the influence of scale multidimensionality on DIF identification. Individuals who investigate DIF in personality assessment applications are provided with estimates regarding the impact of the magnitude of item and trait association and scale multidimensionality on DIF occurrence and effect size. The results emphasize the importance of excluding investigated items in focal trait identification prior to conducting DIF analyses and reporting item and scale psychometric properties in DIF reports.     

From grammatical number to exact numbers: early meanings of 'one', 'two', and 'three' in English, Russian, and Japanese

This study examined whether singular/plural marking in a language helps children learn the meanings of the words 'one,' 'two,' and 'three.' First, CHILDES data in English, Russian (which marks singular/plural), and Japanese (which does not) were compared for frequency, variability, and contexts of number-word use. Then young children in the USA, Russia, and Japan were tested on Counting and Give-N tasks. More English and Russian learners knew the meaning of each number word than Japanese learners, regardless of whether singular/plural cues appeared in the task itself (e.g., "Give two apples" vs. "Give two"). These results suggest that the learning of "one," "two" and "three" is supported by the conceptual framework of grammatical number, rather than that of integers.     

Why do children perseverate when they seem to know better: Graded working memory,or directed inhibition?

Children sometimes have trouble switching from one task to another, despite demonstrating an awareness of current task demands. This behavior could reflect problems either directly inhibiting previously relevant information or sufficiently activating graded working memory representations for the current task. We tested competing predictions from each account, using a computerized card-sorting task in which we assessed children’s task switching abilities and their response speed to simple questions about current task demands. All children answered these questions correctly, but children who successfully switched tasks responded more quickly to questions than did children who perseverated on previous tasks, even after factoring out processing speed and age. This reaction time difference supports graded working memory accounts, with stronger representations of current task demands aiding both task-switching and responses to questions. This result poses a challenge for directed inhibition accounts, because nothing needs to be inhibited to answer simple questions that lack conflicting information.     

Shaping of scientific psychology in Japan

Japanese scientific psychology began with Y. Motora's lecture on pyschophysics at the University of Tokyo in 1888. He had just received his PhD under G.S. Hall at Johns Hopkins University, in the USA. He became the first professor of psychology in 1890 and founded the first psychological laboratory at the University of Tokyo in 1903. He studied many psychological problems, including attention, experimentally and theoretically. One of his first students, Matataro Matsumoto, founded the second psychological laboratory at Kyoto University and then succeeded to Motora's position in Tokyo. Matsumoto was interested in experimental studies of human performance and their applications. He trained many able psychologists and organized the Japanese Psychological Association in 1927. Some of his students founded more psychological laboratories in major universities of Japan. They introduced psychological tests, Gestalt psychology, and behaviourism in the 1920s and 1930s. Psychoanalysis was introduced through mainly nonacademic roots and became familiar to Japanese psychologists in the 1930s. After World War II, a strong influence of American psychology came to Japanese psychologists who had already trained in scientific methodology. The areas of research and applications have been greatly widened and the number of psychologists has increased rapidly up to the present day. Promotion of international interactions and indigenous traditions are both expected.     

The effects of culture on beliefs about stress and coping: Causal attribution of Anglo-American and Japanese persons

This study investigated the effects of culture on beliefs about stress and successful coping. Anglo-American and Japanese samples responded to a questionnaire, and engaged in subsequent interviews as a means of measuring how they would attribute the cause of stress and successful coping. The Japanese subjects were found more likely than Anglo-Americans to attribute successful coping to good luck and to see stress as caused by bad luck. The Japanese persons also showed a stronger tendency to see their lack of carefulness as a cause of stress than American subjects. The implications of the findings of this research study for psychotherapists who treat non-Western clients is also discussed.     

Familiarity breeds searching: infants reverse their novelty preferences when reaching for hidden objects

What infants appear to know depends heavily on how they are tested. For example, infants seem to understand object permanence (that objects continue to exist when no longer perceptible) within the first few months of life when this understanding is assessed through looking measures, but not until several months later when it is assessed through search measures. One explanation of such results is that infants gradually develop stronger representations of objects through experience, and that stronger representations are required for some tasks than for others. The current study confirms one prediction from this account: Stronger representations of familiar objects (relative to novel objects) should support greater sensitivity to their continued existence. After seeing objects hidden, infants reached more for familiar than novel objects, in striking contrast to their robust novelty preferences with visible objects. Theoretical implications concerning the origins of knowledge are discussed.     

Cooperative problem solving by tufted capuchin monkeys (Cebus apella): spontaneous division of labor, communication, and reciprocal altruism

Using an experimentally induced cooperation task, the authors investigated whether tufted capuchin monkeys (Cebus apella) share the following 3 characteristics of cooperation with humans: division of labor, communication, and reciprocal altruism. In Experiment 1, the authors trained individual monkeys to perform the necessary sequence of actions for rewards and tested them in pairs to assess whether they could solve the task by spontaneously dividing the sequence of actions. All pairs solved this task. In Experiment 2, monkeys worked in the cooperation task and a task requiring no partner help. They looked at the partner significantly longer in the former task than in the latter, but communicative intent could not be determined. In Experiment 3, only 1 of 2 participants obtained a reward on each trial. Monkeys maintained cooperation when their roles were reversed on alternate trials. Their cooperative performances demonstrated division of labor; results suggest task-related communication and reciprocal altruism.     

Developmental cognitive neuroscience: progress and potential

Developmental cognitive neuroscience is an evolving field that investigates the relations between neural and cognitive development. Lying at the intersection of diverse disciplines, work in this area promises to shed light on classic developmental questions, mechanisms subserving developmental change, diagnosis and treatment of developmental disorders, and cognitive and neuroscientific topics traditionally considered outside the domain of development. Fundamental questions include: What are the interrelations between developmental changes in the brain (e.g. in connectivity, chemistry, morphology) and developmental changes in children's behavior and cognitive abilities (e.g. representational complexity, ability to sustain selective attention, speed of processing)? Why, and how, is learning enhanced during certain periods in development? How is our knowledge organized, and how does this change with development? We discuss preliminary investigations of such questions and directions for future work.