“…We emphasize, however, that the conceptual issues apply to all psychophysiological studies that correlate individual difference measures with subtraction-based difference scores-a practice that is actually quite common. For instance, recent studies in emotion often subtract neutral from emotional condition averages to quantify individual differences in emotional reactivity (Angus, Kemkes, Schutter, & Harmon-Jones, 2015;Bress, Meyer, & Hajcak, 2015;Burkhouse, Siegle, Woody, Kudinova, & Gibb, 2015;Hoenen, L⏠ubke, & Pause, 2015;Kornilov, Magnuson, Rakhlin, Landi, & Grigorenko, 2015;McTeague, Lang, Laplante, & Bradley, 2011;Meyer, Hajcak, Torpey-Newman, Kujawa, & Klein, 2015;Sylvester, Hudziak, Gaffrey, Barch, & Luby, 2015). Indeed, current recommendations from experts in the field involve "isolating components of interest by creating [subtraction-based] difference waves" (Luck, 2014).…”