Emotional Modulation of the Late Positive Potential during Picture Free Viewing in Older and Young Adults.

Jenna B Renfroe,Margaret M Bradley,Christopher T Sege,Dawn Bowers,Linda Chao

doi:10.1371/journal.pone.0162323

Abstract

Hedonic bias during free viewing of novel emotional and neutral scenes was investigated in older adults and college students. A neurophysiological index of emotional picture processing–the amplitude of the centroparietal late positive potential (LPP)–was recorded from the scalp using a dense sensor array while participants (29 older adults; 21 college students) viewed emotionally engaging or mundane natural scenes that varied in specific content. Both students and older adults showed LPP enhancement when viewing affective, compared to neutral, scenes, and there was no difference in LPP amplitude between older individuals and college students when viewing neutral everyday scenes. However, compared to the college students, older individuals showed attenuated LPP amplitude when viewing emotional scenes, regardless of hedonic valence or specific content. Age related differences could be mediated by a reduction in reactive emotional arousal with age, possible mediated by repeated life exposure to emotional stimuli.

Highlights

There is some evidence that older, relative to younger, adults show a positivity bias during emotional processing, as evidenced by reports of enhanced well being [1], better recall of positive autobiographical events [2], and longer duration of considering positive, relative to negative, attributes of a potential purchase [3]
There was no evidence of hedonic bias in late positive potential (LPP) amplitude during free viewing of novel emotional scenes in older adults or in college students
LPP amplitude was significantly enhanced when viewing pleasant or unpleasant, compared to neutral, scenes, for both college students and older individuals, with neither group showing a significant difference in LPP enhancement when viewing pleasant or unpleasant scenes

Summary

Introduction

There is some evidence that older, relative to younger, adults show a positivity bias during emotional processing, as evidenced by reports of enhanced well being [1], better recall of positive autobiographical events [2], and longer duration of considering positive, relative to negative, attributes of a potential purchase [3]. On the other hand, using three pictures of each hedonic content and a framing task, older adults showed enhanced LPP amplitude for pleasant, compared to unpleasant, scenes regardless of framing instuctions, whereas younger individuals were influenced by the task [16] Each of these findings have been interpreted as supporting a positivity bias in older individuals, the pattern of ERP modulation providing evidence for that interpretation, as well as the paradigm, has varied across studies. The amplitude of the LPP was assessed as older individuals and college students viewed novel pictures depicting erotic couples, romance, nude women, nude men, recreation, snacks, loss, contamination, animal threat, animal threat, and mutilated bodies, together with neutral, scenes depicting everyday people, events, and objects

Participants

Experimental Procedure

Results

Discussion