“…We first look for evidence that infants use abstract representations in MTS and NMTS tasks, and then ask what those representations might be. While we focus on MTS and NMTS, in the general discussion we also consider the representations that might underlie infants’ success on other tasks that probe repesentations of sameness and difference, including habituation to pairs of objects that are the same or to pairs of different objects (Addyman & Mareschal, 2010; Ferry et al, 2015; Tyrell et al, 1991), habituation to patterns specified by pairs of identical elements; e.g., ABA or ABB (Dawson & Gerken, 2009; Johnson et al, 2009; Marcus et al, 1999; Rabagliati et al, 2012; Saffran et al, 2007), and conditioned responses on pairs of identical elements (Hochmann, 2010; Hochmann et al, 2011; Kovács, 2014; Tyrell et al, 1993; Walker & Gopnik, 2014). …”