“…The predictions of the holographic model have been tested empirically and have been shown to accurately relate to behavioural performance (Nucci & Wagemans, 2007) and neural activity (Makin et al, 2016). Makin et al (2016) conducted a large EEG/ERP study to investigate whether the W-metric predicts the amplitude of the symmetry-related component: the sustained posterior negativity (SPN; Bertamini, Silvanto, Norcia, Makin, & Wagemans, 2018;Höfel & Jacobsen, 2007;Jacobsen & Höfel, 2003;Jacobsen, Klein, & Löw, 2018;Makin, Wilton, Pecchinenda, & Bertamini, 2012;Martinovic, Jennings, Makin, Bertamini, & Angelescu, 2018;Wright, Mitchell, Dering, & Gheorghiu, 2018). Briefly, the SPN is a relative component given by the difference in amplitude between ERPs generated by symmetrical (regular) and asymmetrical (irregular) images with same local information.…”