Enhanced Hippocampal CA1 LTP but Normal Spatial Learning in Inositol 1,4,5-trisphosphate 3-kinase(A)-Deficient Mice

To define the physiological role of IP₃3-kinase(A) in vivo, we have generated a mouse strain with a null mutation of the IP₃3-kinase(A) locus by gene targeting. Homozygous mutant mice were fully viable, fertile, apparently normal, and did not show any morphological anomaly in brain sections. In the mutant brain, the IP₄ level was significantly decreased whereas the IP₃ level did not change, demonstrating a major role of IP₃3-kinase(A) in the generation of IP₄. Nevertheless, no significant difference was detected in the hippocampal neuronal cells of the wild-type and the mutant mice in the kinetics of Ca²⁺ regulation after glutamate stimulation. Electrophysiological analyses carried out in hippocampal slices showed that the mutation significantly enhanced the LTP in the hippocampal CA1 region, but had no effect on the LTP in dentate gyrus (DG). No difference was noted, however, between the mutant and the wild-type mice in the Morris water maze task. Our results indicate that IP₃3-kinase(A) may play an important role in the regulation of LTP in hippocampal CA1 region through the generation of IP₄, but the enhanced LTP in the hippocampal CA1 does not affect spatial learning and memory.     

Two dissociable aspects of feeling-of-knowing: knowing that you know and knowing that you do not know

Feeling-of-knowing judgement is traditionally regarded as a unitary cognitive process. However, recent research suggests that knowing that you know (positive feeling-of-knowing) and knowing that you do not know (negative feeling-of-knowing) have different neural substrates (Luo, Niki, Ying, & Luo, 2004). In the present study, we used a paradigm adapted from Koriat and Levy-Sadot (2001) to examine whether positive feeling-of-knowing and negative feeling-of-knowing were mediated by distinct cognitive processes. We found that positive and negative feeling-of-knowing were dissociated during immediate feeling-of-knowing judgements (i.e., preliminary feeling-of-knowing) and delayed feeling-of-knowing judgements (i.e., postretrieval feeling-of-knowing). At the judgement intervals, positive feeling-of-knowing was based on partial recovery of the nonrecalled targets, whereas negative feeling-of-knowing was determined by familiarity with the retrieval cues. Our results suggest that feeling-of-knowing is a heterogeneous process.     

Paradoxical Associations of Masculine Ideology and Casual Sex Among Heterosexual Male Geosocial Networking App Users in China

Momo, the most popular geosocial networking app in China, is used as a common platform to seek casual sex. The present study, which is based on the social constructionist view of gender, examines how the endorsement of masculinity among heterosexual male Momo users is associated with the number of casual sex partners they meet on the app. The study also explores the mediating role of the sex motive for using Momo. Analyses of survey data from 125 heterosexual male Momo users showed that the endorsement of masculinity had an indirect positive relationship with the number of sex partners mediated by the sex motive; at the same time, it had a direct but negative association with the number of sex partners. These paradoxical associations were explained by different patterns across the individual dimensions of masculinity ideology. Specifically, the dimension of the Importance of Sex was responsible for the positive indirect association whereas the dimension of Avoidance of Femininity was responsible for the negative direct association. These findings are discussed in relation to the wen-wu dyad of Chinese masculinity. Because unsafe sex has been found to be associated with the use of geosocial networking apps, my study also calls for integrating the concept of practicing safer sex with the cultural ideal of masculinity.

     

Racial and Religious Convergences and Divergences among Christian Students’ Approaches to Color-Blindness,Color-Cognizance,and Race in Christian Organizations

Drawing on survey data of Christian students (N = 4261) enrolled at 11 colleges that are part of the Council for Christian Colleges and Universities, we examine color-blindness, different types of color-cognizance, and views on race in Christian organizations. We find significant differences between students of color and White students in color-blindness and color-cognizance but find racial convergence in the importance of racial reconciliation. Net of controls, greater evangelical orthodoxy is associated with color-cognizant views that perceive prejudicial treatment against White people, undercut the experiences of people of color, and is associated with more positive views of Christian organizations’ roles in race relationships. Concurrently, upper year students differ significantly from first years in their racial attitudes and views on race in Christian organizations, suggesting that Christian education may shape racial views positively. Our findings have implications for theorizing how evangelical Christianity and evangelical colleges maintain and challenge color-blindness and White supremacy.