Developmental expression of defensive responses during exposure to conspecific adults in preweanling rats (Rattus norvegicus).

I examined preweanling rats' (Rattus norvegicus) expression of ultrasounds and secretion of ACTH when exposed to unfamiliar adult male rats or to their mothers. Pups at 7 days of age produced similar levels of ultrasonic vocalization near both unfamiliar males and mothers. However, these pups could discriminate familiar from unfamiliar adults because ACTH was significantly higher in pups near adult males than in those near mothers. At 14 days of age, pups avoided adult males but not their mothers; therefore, adult males represented a significant threat. Importantly, 14-day-old rats significantly reduced ultrasound production only when near adult males. Pups at 21 days of age no longer emitted ultrasounds when socially isolated or when near conspecific adults. In addition, 14- and 21-day-old rats produced similar elevated ACTH levels across stimulus conditions. Results show significant changes in preweanling rats' responses to conspecific adults.     

Structural connectivity between the hippocampus and cortical/subcortical area relates to cognitive impairment in schizophrenia but not in mood disorders

Cognitive impairment in schizophrenia and other psychiatric disorders is a challenge to be overcome in order to maintain patients' quality of life and social function. The neurological pathogenesis of cognitive impairment requires further elucidation. In general, the hippocampus interacts between the cortical and subcortical areas for information processing and consolidation and has an important role in memory. We examined the relationship between structural connectivity of the hippocampus and cortical/subcortical areas and cognitive impairment in schizophrenia, major depressive disorder and bipolar disorder. Subjects comprised 21 healthy controls, 19 patients with schizophrenia, 20 patients with bipolar disorder and 18 patients with major depressive disorder. Diffusion-weighted tensor images data were processed using ProbtrackX2 to calculate the structural connectivity between the hippocampus and cortical/subcortical areas. Cognitive function was assessed using the Brief Assessment of Cognition in schizophrenia composite score. Hippocampal structural connectivity index was significantly correlated with composite score in the schizophrenia group but not in the healthy control, major depressive disorder or bipolar disorder groups. There were no statistically significant differences in hippocampal structural connectivity index between the four groups. Structural connectivity between the hippocampus and cortical/subcortical areas is suggested to be a pathophysiological mechanism of comprehensive cognitive impairment in schizophrenia.     

Effects of target-background luminance ratios upon the autokinetic illusion

This study investigated effects of the target-background luminance ratios upon the autokinetic illusion, with special emphasis on manipulation of the background intensity. Exp. 1, in which the effects of four levels of target luminance were examined against the completely dark background, showed that the target luminance did not affect the illusion as long as the target was small enough in size (0.17 degrees in visual angle). This result confirmed the suggestion by Edwards in 1954. In Exp. II effects of the target-background luminance ratios were examined by varying the luminance of target and background independently. Dominant illusory patterns at the luminance ratio 1 were "pendulum-like" and "bobbing"; these differed from those at higher ratios ("winding"). On the other hand, latency and duration were not affected by the ratios. These findings suggest that the movement pattern is effective in specifying the autokinetic illusion, if it is appropriately categorized and represented.     

Cultural Styles of Conflict Management in Japanese and Americans: Passivity,Covertness, and Effectiveness of Strategies1

We asked 94 Japanese and 98 American students to report their recent experiences with interpersonal conflicts; they reported 476 episodes. The content analyses of these episodes were conducted in terms of desired and engaged conflict management strategies, effectiveness of chosen strategies, covertness of conflicts, and motives for covertness. Strategies other than simple avoidance were coded into four types, based on Falbo and Peplau's (1980) model. As a result, a particularly strong tendency to avoid conflict was found among Japanese subjects, who were motivated by both their desire to preserve relationships and their perceptions of shared responsibility. These findings were interpreted in terms of cross-cultural concepts of collectivism versus individualism (Triandis, 1989a) and independent versus interdependent self (Markus & Kitayama, 1991).     

Assessing Representations of Close Relationships Among Chinese and Japanese Adolescents and Young Adults: Commonalities and Differences in the Two Confucian Cultures

This article proposed an affective relationships model with its assessment instrument and examined how Chinese and Japanese adolescents and young adults construct mental representations of their close relationships, and the influence of Confucian cultural beliefs on these representations. The participants were 1,565 students aged 14 to 24 years living in China or Japan. The students were asked about their relationships with four figures: mother, father, closest friend, and romantic partner. We found that: (a) adolescents and young adults in both cultures constructed constellations of relationships containing multiple figures, and they articulated reasons for each figure's significance; and (b) there were between-group differences in the relationships with the father and the romantic partner for Chinese versus Japanese adolescents and young adults. These differences were partly explained by the influence of Confucianism on the Chinese participants’ cultural beliefs that retained the patriarchal values.     

Self-rated autistic-like traits and capacity of visual working memory

The effect on the capacity of visual working memory of spatial complexity (as defined by Garner's principle) in rotation and reflection transformation was examined in persons differing along the Autism Spectrum Quotient (AQ), using a change-detection task. On each trial, nine line segments were arrayed in simple, medium, and complex configurations, which were presented in memory and test displays. 27 participants (8 men, 19 women; M age = 22.3 yr., SD = 2.7) were asked whether the orientations of stimuli between two displays were the same or different. On the basis of their AQ scores out of 50 (M AQ scores = 20.9, SD = 6.3), the participants were divided into groups with high (n = 13; M AQ scores = 26.2, SD = 4.1) and low (n = 12; M AQ scores = 15.3, SD = 2.7) self-reported autistic-like traits (High and Low AQ groups, 2 excluded for scores at the median). The results showed that spatial complexity affects the capacity of visual working memory for the Low AQ group but not for the High AQ group, suggesting the functional dissociation of spatial configuration and visual working memory in the High AQ group.     

The Protective Effects of Religious Beliefs on Behavioral Health Factors Among Low Income African American Adolescents in Chicago

Religious involvement has long been argued to have protective effects for negative behavioral health outcomes for vulnerable youth. This study builds on the existing resilience literature and need for more studies that examine protective factors associated with behavioral health. A sample of 638 low-income African American adolescents in Chicago to examine within group variations of the influence of religious involvement on delinquency, school engagement, substance use and sexual risk behaviors, and whether such relationships differ by gender, sexual orientation, and socioeconomic status. Logistic regression findings documented that greater religious involvement was protective with regards to lower rates of delinquency, drug use, risky sexual behaviors and higher rates of school engagement, and that gender, sexual orientation and socioeconomic status varied for several of these relationships. Overall findings are discussed with regards to future research.     

Stability of recent and remote contextual fear memory

Following initial encoding, memories undergo a prolonged period of reorganization. While such reorganization may occur in many different memory systems, its purpose is not clear. Previously, we have shown that recall of recent contextual fear memories engages the dorsal hippocampus (dHPC). In contrast, recall of remote contextual fear memories engages a number of different cortical regions, including the anterior cingulate cortex (ACC). To examine whether this reorganization leads to greater memory stability, we examined reconsolidation of 1 d-old (recent) and 36 d-old (remote) contextual fear memory in mice. We infused the protein synthesis inhibitor, anisomycin (ANI), into either the dHPC or ACC immediately following retrieval of either a recent or remote contextual fear memory. In the dHPC, ANI infusions disrupted subsequent expression of recent, but not remote, contextual fear memory. Similar infusions into the ACC had no effect on either recent or remote contextual fear memories, whereas systemically applied ANI blocked subsequent remote memory expression when long re-exposure durations were used. Together, these data suggest that as memories mature they become increasingly stable. Furthermore, the dissociation between the effects of systemically and centrally administered ANI on remote memory suggests that stability is due, in part, to the distributed nature of remote contextual fear memories.     

One percent ability and ninety-nine percent perspiration: a study of a Japanese memorist

In 1987, Hideaki Tomoyori, a Japanese memorist, set a world record for reciting the first 40,000 digits of pi. The authors report results from a series of tests that give a view of Tomoyori's memory performance compared with that of a control group, matched for age and educational level. He showed very good scores on tasks with digits, such as digit memory span tasks and 5 x 5 number matrix learning, although some of the control participants were nearly as good. In contrast, his performance was not particularly good for learning word lists and story recall. Overall, his performance on the tasks does not suggest that he has superior cognitive abilities. We believe that his extraordinary memory performance in reciting the digits of pi results from his effective use of a combination of digit-syllable transformations and imagery mnemonics developed from extensive practice. These results are consistent with the skilled memory framework.