Response Stereotypy in Humans Maintained by Response-Contingent Events

The present study examined stereotyped behaviors developed during human performances that were generated by response-dependent intermittent schedules of reinforcement. Thirty university students were assigned to either fixed-interval 30-s or fixed-ratio 30-s schedules in which points or monetary reinforcers were produced only by presses on the number keys of a 41-key computer keyboard. Behavior patterns developed by all subjects were classified into four categories: optimal, random, unique, and general stereotypes. The general stereotypes category was further subdivided into five idiosyncratic types: connection, order, shift, repeat, and restriction. Analysis of the data demonstrated the role of contiguity: Whatever behavior happened to precede reinforcers was repeated even though reinforcers did not depend on that behavior. These findings support the argument that much of idiosyncratic and stereotyped human behavior is produced and maintained by contingencies of reinforcement, rather than schedule-induced or adjunctive behavior.     

Psychological Essentialism at the Explicit and Implicit Levels: The Unique Status of Social Categories

Psychological essentialism refers to a naive theory concerning fundamental elements that bring a category into its existence. The present study examined the structure of this lay theory as well as its implicitness, with a special focus on social categories. In Study 1, Japanese college students rated a number of categories that were natural‐kind, social, or human artifacts, in terms of different elements of essentialist beliefs. A factor analysis revealed that entitativity and naturalness are the common underlying dimensions across these category domains. We also identified some natural‐kind and human artifact categories that can be used as two extreme referent points for the examination of naturalness perceived in a whole array of social categories. Study 2 assessed implicit and automatic judgments on naturalness using a go/no‐go task, and compared them to explicit judgments. Unlike natural kinds and artifacts, social categories were essentialized to a greater extent at the implicit level. These results suggest a dual process of intuitive and deliberate cognition, particularly involving social categories, with implications concerning the bases of stereotypes and prejudices.     

The social environments of early infancy in Japan and the United States

The social environments of early infancy in Japan and the United States were compared in terms of the context of caregiving and the quality of the month-infant interaction. Mothers of 17 Japanese infants and 17 infants in the United States were interviewed in their homes about the experiences that they provided for their 4-month-old infants, and mother-infant interactions were recorded on videotape. Levels of parents' education were similar in both countries. The context of the infant's development varied substantially with culture. Mothers in the United States provided a greater variety of experiences on the HOME and care of Japanese infants tended to be more exclusively provided by mothers whereas care of infants in the United States was shared by fathers and other caregivers to a greater extent. Examination of behaviour frequencies during mother-infant interaction indicated that mothers in Japan provided their infants with more vocal input and more physical play than mothers in the United States and Japanese mothers were more vocally responsive to their infants' vocalizations.     

Infant responses to maternal still-face at 4 and 9 months

This study investigated developmental changes in infant responses to maternal still-face (SF) situations. Infants (21 males and 25 females) of Japanese mothers were observed in a face-to-face SF paradigm, comprising four phases (normal/SF/normal/SF), at two infant ages (4 and 9 months). The infants' facial expression, gaze direction, and vocalization were coded in both SF and normal interaction conditions. The results indicated that infants at both ages showed a decrease in displaying positive facial expression and gazing at their mothers during SF conditions. The 4-month-old displayed emotional expression and directed their gaze toward their mothers more frequently than the 9-month-old. However, the 9-month-old vocalized more often in SF situations, attempting to elicit responses from their mothers. The "carry-over" effect was observed only in 9-month-old. The results were discussed in the context of developmental changes in infants' social skills to cope with an emotionally stressful situation.     

Stereoillusory motion concomitant with lateral head movements

Stationary objects in a stereogram can appear to move when viewed with lateral head movements. This illusory motion can be explained by the motion-distance invariance hypothesis, which states that illusory motion covaries with perceived depth in accordance with the geometric relationship between the position of the stereo stimuli and the head. We examined two predictions based on the hypothesis. In Experiment 1, illusory motion was studied while varying the magnitude of binocular disparity and the magnitude of lateral head movement, holding viewing distance constant. In Experiment 2, illusory motion was studied while varying binocular disparity and viewing distance, holding magnitude of head movement constant. Ancillary measures of perceived depth, perceived viewing distance, and perceived magnitude of lateral head movement were also obtained. The results from the two experiments show that the extent of illusory motion varies as a function of perceived depth, supporting the motion-distance invariance hypothesis. The results also show that the extent of illusory motion is close to that predicted from the geometry in crossed disparity conditions, whereas it is greater than the predicted motion in uncrossed disparity conditions. Furthermore, predictions based on perceptual variables were no more accurate than predictions based on geometry.     

Enhanced uniform elongation by pre-straining with deformation twinning in high-strength β-titanium alloys with an isothermal ω-phase

It is shown that pre-straining with deformation twinning is a novel approach to enhancing the uniform elongation of a high-strength β-type Ti–15Mo alloy (mass%) with isothermal ω-phase precipitation. Pre-existent mechanical {3?3?2}?1?1?3? twins hinder the early onset of plastic instability (necking) after yielding, which is often caused by the presence of the isothermal ω-phase, and enhance the uniform elongation markedly from 0% to 13% at a yield strength level of 900?MPa.     

Attacked by the gods or by mental illness? Hybridizing mental and spiritual health in Okinawa

In 1972, the reversion to Japanese rule brought with it many changes for Okinawans, among them the widespread introduction of psychiatry. Psychiatry was not well received at first due to the extensive presence of shamans, who had traditionally dealt with Okinawans’ spiritual and psychological afflictions. Both psychiatrists and shamans claimed to be able to heal those who were labelled ‘mentally ill’ or ‘mentally disordered’ by psychiatrists. This conflict between systems over the body of the patient/client is relevant to debates today about both the perceived value of generic mental health diagnosis and treatment regimes compared with indigenous healing,1 See Kleinman (, ); WHO (2001).  [Google Scholar] and the question of isolating how markers or symbols of identity are employed in patients’ help-seeking choices. We examine three cases from the 1970s of patients who were diagnosed as suffering from both schizophrenia and an indigenous condition known as kami daarii.     

<Emphasis Type="Italic">Kowakare:</Emphasis> A New Perspective on the Development of Early Mother–Offspring Relationship

The mother–offspring relationship has components of both positivity and negativity. Kowakare is a new concept introduced to explain an adaptive function of the negativity in the early mother-offspring relationship. Kowakare is the psycho-somatic development of the relationship as the process of accumulation in the otherness of offspring. Early human Kowakare has two frameworks, biological inter-body antagonism and socio-cultural allomothering compensating the antagonism. Some features of feeding/weaning, parental aversion to offspring’s bodily products, and transition from dyad to triad relationship (proto–triad relationship) in tactile play are discussed. Early human Kowakare is promoted by allomothering with the nested systems of objects/persons/institutions as interfaces between mother and offspring. Kowakare makes mother–offspring relationship a mutually autonomous and cooperative companionship.