Keeping an eye on the truth? Pupil size changes associated with recognition memory

Abstract

During recognition memory tests participants" pupils dilate more when they view old items compared to novel items. We sought to replicate this "pupil old/new effect" and to determine its relationship to participants" responses. We compared changes in pupil size during recognition when participants were given standard recognition memory instructions, instructions to feign amnesia and instructions to report all items as new. Participants" pupils dilated more to old items compared to new items under all three instruction conditions. This finding suggests that the increase in pupil size that occurs when participants encounter previously studied items is not under conscious control. Given that pupil size can be reliably and simply measured, the pupil old/new effect may have potential in clinical settings as a means for determining whether patients are feigning memory loss.

Emotional arousal and recognition memory are differentially reflected in pupil diameter responses during emotional memory for negative events in younger and older adults

“…Studies investigating PD during memory encoding or recognition tasks have furthermore consistently shown larger PD responses to old as opposed to novel stimuli (recognition effect, also known as familiarity effect) (Heaver and Hutton, 2011;Otero et al, 2011;Võ et al, 2008). These larger PD responses to old compared to new stimuli have been attributed to increased effort necessary for memory retrieval (Võ et al, 2008).…”

Pupil dilation during recognition memory: Isolating unexpected recognition from judgment uncertainty

“…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.…”

Male bisexual arousal: A matter of curiosity?

“…Lammens, Overeem, & Keyser, 2011). Other research suggests that pupil dilation reflects attention that is likely not in the conscious control of participants (Heaver & Hutton, 2011). For these reasons, pupil dilation has been used as an indicator of automatic responses, including responses reflecting sexual arousal (Goldinger & Papesh, 2012;Laeng, Sirois, & Gredebäck, 2012).…”