Prevailing theories propose that confidence in two-alternative forced-choice decisions is based on the probability that the selected option is correct. However, recent findings from three-alternative tasks suggest that adults' confidence might irrationally reflect the difference between the probabilities of the best and next-best options only, with other options disregarded. Using a novel probability task (in which participants guess the colour of a ball to be randomly selected from varying distributions) and a uniquely sensitive confidence measure, we investigated metacognition in multi-option decision making in children (N = 97, aged 6-9-years) and adults (N = 51). Contrary to previous findings, children's and adults' confidence was primarily explained by the probability of the best option. However, preliminary findings suggest that among older children and adults, additional irrelevant factors also accounted for unique variance in confidence. In some contexts, human confidence might be initially calibrated rationally but increasingly reflect irrational factors over development.

The ‘Self’ has a prioritized cognitive status, attributed to an automatic bottom-up attentional enhancement for self-relevant stimuli. Two predictions follow if self-relevant information is automatically boosted. First, processing should be enhanced for self- compared to other-relevant targets. Second, interference should be greater for self- compared to other-relevant distractors. To investigate these predictions, we adapted a motion reproduction task. Participants first learned to associate a colour (blue, pink) with themselves and a stranger (other), then viewed a label (YOU or OTHER) and two different coloured superimposed random dot kinematograms (RDKs; blue, pink). A response dial recorded participants’ reproduced direction of motion for the coloured RDK associated with the presented label. Facilitation and interference for self- and other-labelled features was assessed by the angular difference between the reported and true direction of motion (signed error magnitude). There was a small, but reliable response bias in direction of distractor motion showing that attentional selection was imperfect. Further regression-based analyses quantified the degree to which self and other-related stimuli influenced responses (decision weights). As predicted, decision weights for target stimuli showed a significant advantage for self- compared with other-relevant motions. By contrast distractor weights did not differ significantly between self- and other-relevant features, suggesting self-relevance did not modulate the degree of interference and self-relevant stimuli did not automatically capture attention. Overall, we show that feature-based attention is enhanced for self-associated sensory input, but only when task-relevant.