“…Alongside an intellectual impairment, typically in the mild to moderate range (Martens, Wilson, & Reutens, 2008), one of the cardinal features of WS is a unique social phenotype, with affected individuals displaying hypersocial behavior and a drive for social engagement and interaction, both with familiar others and with strangers (Bellugi, Adolphs, Cassady, & Chiles, 1999;Doyle, Bellugi, Korenberg, & Graham, 2004;Jones et al, 2000;Thurman & Fisher, 2015). In addition to this hypersociability, empirically, individuals with WS generally display a striking bias toward positive social stimuli, particularly happy facial expressions, which has been demonstrated across neurological (Haas et al, 2009;Haas & Reiss, 2012), physiological (Jarvinen et al, 2015;Plesa Skwerer et al, 2009), and attentional (Dodd & Porter, 2010;Goldman, Shulman, Bar-Haim, Abend, & Burack, 2017) measures. This strong positive bias is thought to at least partially underlie the heightened and indiscriminate social approach (Jarvinen, Korenberg, & Bellugi, 2013) and social trust (Riby, Kirk, Hanley, & Riby, 2014) reported in this population.…”