“…The pupil is also sensitive to episodic memory judgments, dilating more for recognition probes identified as studied (old) versus unstudied (new) (Gardner, Mo, & Borrego, 1974;Heaver & Hutton, 2011;Naber, Frassle, Rutishauser, & Einhauser, 2013;Papesh, Goldinger, & Hout, 2012;Vo et al, 2008). As an extension of earlier work linking pupillary dilation to cognition (Beatty, 1982;Kahneman, 1973), this 'pupil old/new effect' has been suggested to reflect the increased 'cognitive load' or voluntary effort required during the successful retrieval of episodic content.…”