UCLA

This dissertation aims to contribute to the understanding of how biological signals interact to support complex social communication by presenting three papers examining the neural and behavioral impacts of age and neuropeptide hormones on deception detection accuracy. In Paper 1, published in the Proceedings of the National Academy of Science and co-authored by Naomi I. Eisenberger, Teresa E. Seeman, Wesley G. Moons, Ian A. Boggero, Mark S. Grinblatt and Shelley E. Taylor, we use behavioral and neuroimaging methods to identify age differences in judgments of trustworthiness and the neural underpinnings of these patterns. I find that older adults show muted activation of the anterior insula in response to untrustworthy faces, as well as the tendency to rate untrustworthy faces as much more trustworthy than they are, particularly in comparison to younger adults. I discuss the implications of this work for older adults’ vulnerability to fraud. In Paper 2, I build on the findings of Paper 1, by testing whether similar age differences are observed in the context of deception detection and whether older adult’s tendency towards the positivity might compromise their accuracy. I find partial support for this hypothesis, with positive cues predicting decreased accuracy in older adults but not younger adults. In Paper 3, I explore two hormones, oxytocin and vasopressin, and their impact on deception detection. I find that vasopressin, but not oxytocin, improves deception detection. These findings lead us to a better understanding of how neuropeptides support human social regulation.