The neural basis of metacognitive ability

Abstract

Ability in various cognitive domains is often assessed by measuring task performance, such as the accuracy of a perceptual categorization. A similar analysis can be applied to metacognitive reports about a task to quantify the degree to which an individual is aware of his or her success or failure. Here, we review the psychological and neural underpinnings of metacognitive accuracy, drawing on research in memory and decision-making. These data show that metacognitive accuracy is dissociable from task performance and varies across individuals. Convergent evidence indicates that the function of the rostral and dorsal aspect of the lateral prefrontal cortex (PFC) is important for the accuracy of retrospective judgements of performance. In contrast, prospective judgements of performance may depend upon medial PFC. We close with a discussion of how metacognitive processes relate to concepts of cognitive control, and propose a neural synthesis in which dorsolateral and anterior prefrontal cortical subregions interact with interoceptive cortices (cingulate and insula) to promote accurate judgements of performance.

Figure 1.

(a) A schematic adapted from Shimamura [16] showing how the levels of Nelson and Narens' cognitive psychology model of metacognition can be naturally mapped onto a hierarchical brain structure. (b) The left panel shows a first-order process, such as a simple visual discrimination, that may occur in the absence of metacognitive report. The right panel shows the same discrimination, this time with the information available for a second-order commentary about the decision.

Figure 2.

(a) Contingency tables for (i) type 1 SDT, and (ii) type 2 SDT. Rows correspond to objective states of the world; columns correspond to subjects' reports about the world; FA, false alarm; CR, correct rejection. In the type 2 table, ‘high’ and ‘low’ refer to decision confidence. The linking arrow and colour scheme indicates that ‘correct’ and ‘incorrect’ states of the world for the type 2 analysis are derived from averaging particular type 1 outcomes. (b) (i) Example of a type 2 receiver operating characteristic (ROC) function for a single subject in a perceptual decision task where performance is held constant using a staircase procedure. The shaded area indicates the strength of the relationship between performance and confidence. (ii) Theoretical type 2 ROC functions for different levels of type 1 d′ (assuming neutral type 1 response criteria) demonstrating that metacognitive accuracy is predicted to increase as task performance increases.

Figure 3.

Data from a visual decision task demonstrating a dissociation of metacognitive accuracy from task performance. Subjects made a visual decision (either an orientation or contrast judgement) and then provided a retrospective confidence rating. A measure of metacognitive accuracy was derived from these ratings by calculating the area under the type 2 ROC function. Performance on the orientation judgement task did not predict task performance on the contrast judgement task (a). However, metacognitive accuracy was strongly correlated between tasks (b), suggesting that it is both independent of task performance and stable within individuals. Reproduced with permission from Song et al. [70].

Figure 4.

Convergent evidence for a role of rostrolateral PFC in metacognitive accuracy. (a) Across individuals, grey matter volume in rlPFC was found to positively correlate (hot colours) with metacognitive accuracy (type 2 ROC area) after controlling for differences in task performance [21]. (b) In a complementary study, BOLD signal in right posterior-lateral BA10 was positively correlated with metacognitive accuracy (gamma) but not differences in task performance [96]. (c) The necessity of lateral PFC for metacognitive accuracy was confirmed by combining TMS with SDT: following repetitive TMS to bilateral dlPFC, subjects exhibited reduced meta-d′ (the type 2 d′ expected from a given level of type 1 sensitivity) despite intact task performance [20]. Panels reproduced with permission from [21,96,20].