Exposure to negative stereotypes influences representations of monetary incentives in the nucleus accumbens

Contemporary society is saturated with negative representations of racial and ethnic minorities. Social science research finds that exposure to such negative stereotypes creates stress above and beyond pre-existing effects of income inequality and structural racism. Neuroscience studies in animals and humans show that life stress modulates brain responses to rewards. However, it is not known whether contending with negative representations of one's social group spills overs to influence reward processing. We used functional magnetic resonance imaging to examine the effects of stigmatizing negative stereotypes on neural responding to the anticipation and consumption of monetary gains and losses in a Mexican American sample. Machine learning analyses indicated that incentive-related patterns of brain activity within the nucleus accumbens differed between Mexican Americans subjected to negative stereotypes and those who were not. This effect occurred for anticipating both gains and losses. Our work suggests that rhetoric stigmatizing Latinos and other minorities could alter how members of such groups process incentives in their environment. These findings contribute to our understanding of the linkage between stigmatizing experiences and motivated behavior, with implications for well-being and health

Performance Comparison of Graphene Nanoribbon FETs with Schottky Contacts and Doped Reservoirs

We present an atomistic 3D simulation study of the performance of graphene nanoribbon (GNR) Schottky barrier (SB) FETs and transistors with doped reservoirs (MOSFETs) by means of the self-consistent solution of the Poisson and Schrodinger equations within the non-equilibrium Green's function (NEGF) formalism. Ideal MOSFETs show slightly better electrical performance, for both digital and THz applications. The impact of non-idealities on device performance has been investigated, taking into account the presence of single vacancy, edge roughness and ionized impurities along the channel. In general, MOSFETs show more robust characteristics than SBFETs. Edge roughness and single vacancy defect largely affect performance of both device types.Comment: to appear in IEEE Trans. on Electron Device

Top-down influences of mere group membership on face representations: The roles of ingroup positivity, category labels, and the self

How do people determine what an ingroup looks like? Past research using a minimal group paradigm suggests that people imbue ingroups with physical features that convey desirable attributes. In this research, I used the classic overestimator versus underestimator and Klee versus Kandinsky minimal group paradigms and the reverse correlation method to examine various top-down influences of mere group membership on face representations of ingroup and outgroup, beyond the well-documented ingroup positivity effect. In Study 1a, I show that participants represented ingroup faces more favorably than outgroup faces, but also represented faces of overestimator and underestimator groups differently. In fact, the category label effect was larger than the ingroup positivity effect. In Study 1b, I demonstrate that faces of Klee and Kandinsky groups were also represented differently at the group-level, but not at the participant-level. This lack of category label effect was in turn related to a stronger ingroup positivity effect. In Study 2a and 2b, I show that people were more likely to use their own self-image to mentally represent ingroup faces than outgroup faces. In Study 3a and 3b, I show that self-evaluation was related to the extent to which ingroup positivity bias was expressed in people’s mental representation of ingroup and outgroup faces, more so than group-evaluation, and also provide a potential alternative explanation for the findings from Study 2. Together, this work advances but does not upend understanding of minimal group effects. I robustly replicate the ingroup positivity effect in face representations. At the same time, I demonstrated other top-down influences of such as category labels as well as the self-knowledge play on how people visually represent faces of minimal ingroup and outgroup members