Electrophysiological Differences in the Processing of Affect Misattribution

Yohei Hashimoto,Shigeki Nakauchi,Tetsuto Minami,Thomas Koenig

doi:10.1371/journal.pone.0049132

Yohei Hashimoto, Shigeki Nakauchi + Show 2 more

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https://doi.org/10.1371/journal.pone.0049132

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Journal: PloS one	Publication Date: Nov 7, 2012
Citations: 38	License type: CC BY 4.0

Affiliation: Toyohashi University of Technology

Abstract

The affect misattribution procedure (AMP) was proposed as a technique to measure an implicit attitude to a prime image [1]. In the AMP, neutral symbols (e.g., a Chinese pictograph, called the target) are presented, following an emotional stimulus (known as the prime). Participants often misattribute the positive or negative affect of the priming images to the targets in spite of receiving an instruction to ignore the primes. The AMP effect has been investigated using behavioral measures; however, it is difficult to identify when the AMP effect occurs in emotional processing—whether the effect may occur in the earlier attention allocation stage or in the later evaluation stage. In this study, we examined the neural correlates of affect misattribution, using event-related potential (ERP) dividing the participants into two groups based on their tendency toward affect misattribution. The ERP results showed that the amplitude of P2 was larger for the prime at the parietal location in participants showing a low tendency to misattribution than for those showing a high tendency, while the effect of judging neutral targets amiss according to the primes was reflected in the late processing of targets (LPP). In addition, the topographic pattern analysis revealed that EPN-like component to targets was correlated with the difference of AMP tendency as well as P2 to primes and LPP to targets. Taken together, the mechanism of the affective misattribution was closely related to the attention allocation processing. Our findings provide neural evidence that evaluations of neutral targets are misattributed to emotional primes.

Highlights

IntroductionPrevious studies [3,4,5] have demonstrated that the time to evaluate a target item as either ‘‘happy’’ or ‘‘sad’’ is shorter when the prime and target pairs are affectively congruent (e.g., positive-positive) than when they are affectively incongruent (e.g., positive-negative)
The behavioral approach has provided important information concerning the affect misattribution procedure (AMP) effect; it is difficult to identify when the AMP effect occurs in emotional processing—whether the effect may occur in the earlier attention allocation stage or in the later evaluation stage
As to the reaction times, there is no significant main effect [prime valence: F (2, 36) = 0.41, p = 0.42, and misattribution tendency: F (1, 18) = 0.44, p = 0.38] and interaction [F(2, 36) = 0.89, p = 0.42 ]. These results indicate that the misattribution index (Mindex) was suitable for the classification of AMP effects

Summary

Introduction

Previous studies [3,4,5] have demonstrated that the time to evaluate a target item as either ‘‘happy’’ or ‘‘sad’’ is shorter when the prime and target pairs are affectively congruent (e.g., positive-positive) than when they are affectively incongruent (e.g., positive-negative) This phenomenon is referred to as an affective priming effect. Participants are instructed to ignore the prime picture and to rate the pleasantness (i.e., whether like or dislike) of the target pictographs During these trials, they often misattribute the positive or negative affect of the priming images to the targets in spite of the instruction to ignore the primes (e.g., a positive response to a neutral target that follows positive primes)

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