Active Confirmation Bias in the Evaluative Processing of Food Images

Abstract

Predictive processing is fundamental to many aspects of the human mind, including perception and decision-making. It remains to be elucidated, however, in which way predictive information impacts on evaluative processing, particularly in tasks that employ bivalent stimulus sets. Various accounts, including framing, proactive interference, and cognitive control, appear to imply contradictory proposals on the relation between prediction and preference formation. To disambiguate whether predictive cues produce congruent biases versus opponent mechanisms in evaluative processing, we conducted two experiments in which participants were asked to rate individual food images. The image database included appetitive and aversive items. In each trial, a cue predicted, with varying degrees of reliability, the valence of the impending food image. In both experiments, we found that the ratings exhibited congruent biases as a function of the reliability of the predictive cue, with the highest evaluations following the most reliable positive-valence predictions. Eye prepositioning further showed a selective spatial bias suggestive of response preparation in line with the predictions. The response times also exhibited a pattern of results consistent with selective preparation, producing slow responses following invalid predictions. The data suggested an active form of evaluative processing, implementing a confirmation bias that aims to accommodate the prediction.

Tracking the Influence of Predictive Cues on the Evaluation of Food Images: Volatility Enables Nudging

“…In our previous study (Ounjai et al, 2018), analysis of the reaction times further showed that valid predictions (e.g., a positive prediction followed by an appetitive food image) produced faster evaluations than invalid predictions. Moreover, during the waiting period between the predictive cue and the target image, we observed gaze biases indicative of a preparatory process in line with the prediction.…”

“…Would we see bias in line with the prediction (higher ratings for expected treats) or an opposite effect (higher ratings for surprise treats)? In our previous study, we asked this question empirically, using an evaluation task with a bivalent set of food images (Ounjai et al, 2018). Our data showed that appetitive food images were rated higher following a positive prediction than following a negative prediction, and vice versa for aversive food images.…”

“…Bivalent predictive cues produce an active confirmation bias in a value-based judgment task with naturalistic food images (Ounjai et al, 2018). Here, we investigated the operation of the confirmation bias as a function of the size of the expectation violation.…”

“…The current study is based on a reanalysis of the data set that was published previously by Ounjai et al (2018). For present purposes, we considered only the manual joystick responses with the evaluative ratings, particularly in trials with positive or negative predictive cues that could produce expectation violations.…”

“…Analogous to the concept of nudging in behavioral economics (Thaler and Sunstein, 2008; see also Noggle, 2018), we label this hypothesis as "nudging in volatility." Concretely, reanalyzing our previous data (Ounjai et al, 2018), we investigate in the present study how the confirmation bias operates with strong versus mild images. According to the predictive dissonance hypothesis, the confirmation bias should be more pronounced for strongly polarized food images than for less polarized food images.…”