Differences in Neural Response to Romantic Stimuli in Monogamous and Non-Monogamous Men

Understanding identification-based trust in the light of affiliative bonding: Meta-analytic neuroimaging evidence

Trust is vital for establishing social relationships and is a crucial precursor for affiliative bonds. Investigations explored the neuropsychological bases of trust separately (e.g., measured by the trust game) and affiliative bonding (e.g., measured by parental care, pair-bonding, or friendship). However, direct empirical support for the shared neural mechanisms between trust and affiliative bonding is missing. Here, we conducted a coordinate-based meta-analysis on functional magnetic resonance imaging studies on interpersonal trust and affiliative bonding using the activation likelihood estimation method. Our results demonstrated that decisions to trust strangers in repeated interactions (i.e., identification-based trust) engaged the ventral striatum (vSTR, part of the mesolimbic dopaminergic pathway), likely signaling the reward anticipation. Further, both feedbacks in repeated interactions and affiliative bonding engaged the dorsal striatum (dSTR, part of the nigrostriatal dopaminergic pathway), likely encoding learning dynamics. Our findings suggest that identification-based trust can be understood in the light of affiliative bonding, involving the mesocorticolimbic "reward" pathway (vSTR) and nigrostriatal "habit formation" pathway (dSTR) in building and sustaining social relationships.

Behavioral and neural evidence for an evaluative bias against other people's mundane interracial encounters

Evaluating other people’s social encounters from a third-person perspective is an ubiquitous activity of daily life. Yet little is known about how these evaluations are affected by racial bias. To overcome this empirical lacuna, two experiments were conducted. The first experiment used evaluative priming to show that both Black (n = 44) and White Americans (n = 44) assess the same mundane encounters (e.g. two people chatting) less favorably when they involve a Black and a White individual rather than two Black or two White individuals. The second experiment used functional magnetic resonance imaging to demonstrate that both Black (n = 46) and White Americans (n = 42) respond with reduced social reward processing (i.e. lower activity in the ventral striatum) and enhanced mentalizing (e.g. higher activity in the bilateral temporal–parietal junction) toward so-called cross-race relative to same-race encounters. By combining unobtrusive measures from social psychology and social neuroscience, this work demonstrates that racial bias can affect impression formation even at the level of the dyad.