Consistent patterns of distractor effects during decision making

Abstract

<jats:p>The value of a third potential option or distractor can alter the way in which decisions are made between two other options. Two hypotheses have received empirical support: that a high value distractor improves the accuracy with which decisions between two other options are made and that it impairs accuracy. Recently, however, it has been argued that neither observation is replicable. Inspired by neuroimaging data showing that high value distractors have different impacts on prefrontal and parietal regions, we designed a dual route decision-making model that mimics the neural signals of these regions. Here we show in the dual route model and empirical data that both enhancement and impairment effects are robust phenomena but predominate in different parts of the decision space defined by the options' and the distractor's values. However, beyond these constraints, both effects co-exist under similar conditions. Moreover, both effects are robust and observable in six experiments.</jats:p>

Intraparietal stimulation disrupts negative distractor effects in human multi-alternative decision-making

“…Eye-tracking Data Analysis. Apart from the MIP-related negative distractor effect, the MIP-unrelated positive distractor effect is associated with overt attention that is re ected by eye-movement 6,19 . Here, we hypothesise that this effect is increased when TMS is applied over MIP, disrupting the positive distractor effect's antagonist.…”

“…Speci cally, the negative distractor effect is most prominent in decisions that are easy or with options that are generally poor; whereas the positive distractor effect is most prominent in decisions that are di cult or with options that are generally valuable (Figures 2c, d and S1). These variations in the distractor effects are captured by a dual-route model that simply incorporates both a divisive normalisation mechanism and a mutual inhibition mechanism in separate decision routes 19 . The current results again suggest an association between these different routes and different brain regions.…”

“…In addition, divisive normalisation models also predict that the size of the negative distractor effect should be smaller when the total HV+LV is large 19 . This is because the variance in D then makes a smaller contribution to the overall normalisation effect that depends on HV+LV+D.…”

“…Participants completed a multi-alternative value-based decision-making task that was similar to that of previous studies 6,19 (Figure 1a). In each trial, three coloured rectangles were presented and participants were asked to choose the best option.…”

Dissociable mechanisms of reward learning co-mature during human adolescence as predicted by macaque lesion models

“…By contrast, if the more medial orbitofrontal regions mature faster than the lateral regions, as visually suggested by current developmental maps (Gogtay et al ., 2004), then we hypothesize that decision-making processes linked to these regions may not show similar developmental changes during adolescence. We test this hypothesis by examining a type of decision-making bias that occurs in multi-option environments and depends on medial prefrontal cortex: how the comparison of two option is influenced by an irrelevant third alternative (Ray, 1973; Noonan et al ., 2010; Louie et al ., 2011; Louie et al ., 2013; Chau et al ., 2014; Noonan et al ., 2017; Chau et al ., 2020).…”