Is there an age-related attentional bias towards positive information presented outside focussed attention?

Abstract

Cognitive aging is typically associated with improved emotional regulation and increased positive affect. It is theorized that this results from age-related positivity bias in attention. Although there is some evidence of positivity bias in controlled attention, it remains unclear whether positivity bias extends to the attentional processing of affective stimuli outside focussed attention. To address this question two experiments asked: Firstly, do to-be-ignored affective images presented outside focussed attention receive attentional processing? Secondly, does interference (or facilitation) of directed-task performance vary as a function of to-be-ignored flanker valence? Thirdly, do young and older adults differ in respect to interference (or facilitation) from affective distractors? In the first experiment, 26 older adults, and 30 young adults, performed a multi-source interference task embedded within a flanker paradigm. The directed task involved identifying a target digit within a centrally presented three digit array. Flankers were images with positive, neutral, or negative valence taken from the International Affective Picture System (IAPS). There were no significant differences in response times for either age group when comparing positive and neutral, or negative and neutral flanker trials. This suggests, task-irrelevant affective stimuli are not unconditionally processed outside focussed attention. In a second experiment, 30 older adults, and 30 young adults, made speeded valence judgements for centrally presented positive and negative IAPS images that were flanked above and below by to-be-ignored negative, neutral, or positive IAPS images. Flankers were task-relevant because both target and flankers possessed affective valence, and because the directed task required participants to make valence judgements. There was evidence of interference in negative target with incongruent (positive) flanker trials and facilitation in positive target with congruent (positive) flanker, indicating task-relevant affective stimuli outside of focussed attention were processed. Experiment 2 did not provide evidence of the positivity effect outside controlled attention because young and older adults did not differ significantly in respect to distractor effects from positive or negative affective stimuli. Consistent with age-related positivity bias in controlled attention, older, but not young adults responded faster in positive relative to negative target trials. These findings are consistent with the view that positivity effect is reliant on controlled attention however further research is needed to determine whether this is the case for all classes of affective stimuli unconditionally.