Memory, emotion, and pupil diameter: Repetition of natural scenes

Abstract

Recent studies have suggested that pupil diameter, like the "old-new" ERP, may be a measure of memory. Because the amplitude of the old-new ERP is enhanced for items encoded in the context of repetitions that are distributed (spaced), compared to massed (contiguous), we investigated whether pupil diameter is similarly sensitive to repetition. Emotional and neutral pictures of natural scenes were viewed once or repeated with massed (contiguous) or distributed (spaced) repetition during incidental free viewing and then tested on an explicit recognition test. Although an old-new difference in pupil diameter was found during successful recognition, pupil diameter was not enhanced for distributed, compared to massed, repetitions during either recognition or initial free viewing. Moreover, whereas a significant old-new difference was found for erotic scenes that had been seen only once during encoding, this difference was absent when erotic scenes were repeated. Taken together, the data suggest that pupil diameter is not a straightforward index of prior occurrence for natural scenes.

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

“…Finally, in further support that the emotional PD effect observed was driven by the negative emotional impact of the presented pictures, we observed an increased effect of stimulus emotionality on PD for novel pictures in particular (Bradley and Lang, 2015).…”

“…An increased PD response to negative stimuli is a consistent effect in the literature (Bradley et al, 2008;Bradley and Lang, 2015;Partala and Surakka, 2003;van Stegeren, 2008) and thought to reflect phasic bottom-up influences on the LC-NA system elicited by salient stimulus properties (Sara and Bouret, 2012). Furthermore, we add to this literature by showing that an increase in PD to negative stimuli is especially pronounced in older adults who are more susceptible to emotional stimulation, as evident in longer RTs to negative stimuli.…”

Getting directions from the hippocampus: The neural connection between looking and memory

“…When humans freely view images, the pupil diameter is larger for repeated images ~850 ms after image onset, and maintains this relative size differential between novel and repeated images for at least several seconds (Bradley and Lang, 2015). The magnitude and rate of pupil constriction in response to a novel image has also been shown to predict declarative memory for that image (Bradley and Lang, 2015; Kafkas and Montaldi, 2011; Naber, Frässle, Rutishauser, and Einhauser, 2013). …”

“…Supportive of the idea that a single output from the MTL to the LC may cause both memory-dependent behaviors is the fact that these behaviors share an onset time. Pupil constriction with repeated images and the lengthening of fixation duration with repeated images manifest at about the same time (~850 ms after image onset (Bradley and Lang, 2015; Miriam Meister and Seth Koenig, personal communication)). Future research investigating MTL output to oculomotor structures could constitute a major step forward for understanding the generation of eye movements and the general neural mechanisms by which memory influences behavior.…”

The pupil response as an indicator of user experience in a digital exercise game

“…Since it was first discovered that “increases in the size of the pupil of the eye have been found to accompany the viewing of emotionally toned or interesting visual stimuli” (Hess & Polt, , p. 349), the use of pupil reactions for measuring emotions has evolved (Janisse, ; Libby, Lacey, & Lacey, ; Mudd, Conway, & Schindler, ; for an overview of early studies, see Goldwater, ). Today, measuring pupil size variations in response to standardized and typically stationary stimuli (such as IAPS pictures) is an established psychophysiological method for measuring emotions (Bradley & Lang, ; Bradley et al, ; Henderson, Bradley, & Lang, ; Snowden et al, ; van Steenbergen, Band, & Hommel, ). The present study aims to explore whether the pupil response is equally suited to remotely measure (phasic) emotional reactions occurring in a gaming context.…”