“…We focus on two commonly used RT transformations. The first is to take proportional RT costs, in which the raw RT cost is divided by the mean RT in the baseline condition (e.g., Bialystok, Craik, & Luk, 2008 ; Colcombe, Kramer, Erickson, & Scalf, 2005 ; de Bruin & Della Sala, 2018 ; Gold, Kim, Johnson, Kryscio, & Smith, 2013 ; Gratton, Wee, Rykhlevskaia, Leaver, & Fabiani, 2009 ; Henry et al, 2015 ; Kousaie & Phillips, 2012 ; Lawo & Koch, 2014 ; Mazaheri, Roerdink, Duysens, Beek, & Peper, 2016 ; Truong & Yang, 2014 ; Weissberger, Wierenga, Bondi, & Gollan, 2012 ; Yang & Hasher, 2007 ; Zhu, Zacks, & Slade, 2010 ). The second transformation is the z -score, in which the overall mean RT is subtracted from each trial RT, and the result divided by the overall SD .…”