Understanding how people rate their confidence is critical for characterizing a wide range of perceptual, memory, motor, and cognitive processes. To enable the continued exploration of these processes, we created a large database of confidence studies spanning a broad set of paradigms, participant populations, and fields of study. The data from each study are structured in a common,

Metacognition is the capacity to introspectively monitor and control one's own cognitive processes. Previous anatomical and functional neuroimaging findings implicated the important role of the precuneus in metacognition processing, especially during mnemonic tasks. However, the issue of whether this medial parietal cortex is a domain-specific region that supports mnemonic metacognition remains controversial. Here, we focally disrupted this parietal area with repetitive transcranial magnetic stimulation in healthy human participants of both sexes, seeking to ascertain its functional necessity for metacognition in memory versus perceptual decisions. Perturbing precuneal activity selectively impaired metacognitive efficiency of temporal-order memory judgment, but not perceptual discrimination. Moreover, the correlation in individuals' metacognitive efficiency between domains disappeared when the precuneus was perturbed. Together, these findings provide evidence reinforcing the notion that the precuneal region plays an important role in mediating metacognition of episodic memory retrieval. Theories on the neural basis of metacognition have thus far been largely centered on the role of the prefrontal cortex. Here we refined the theoretical framework through characterizing a unique precuneal involvement in mnemonic metacognition with a noninvasive but inferentially powerful method: transcranial magnetic stimulation. By quantifying metacognitive efficiency across two distinct domains (memory vs perception) that are matched for stimulus characteristics, we reveal an instrumental role of the precuneus in mnemonic metacognition. This causal evidence corroborates ample clinical reports that parietal lobe lesions often produce inaccurate self-reports of confidence in memory recollection and establish the precuneus as a nexus for the introspective ability to evaluate the success of memory judgment in humans.

Background: A recent virtual-lesion study using inhibitory repetitive transcranial magnetic stimulation (rTMS) confirmed the causal behavioral relevance of the precuneus in the evaluation of one's own memory performance (aka mnemonic metacognition).Objective: This study's goal is to elucidate how these TMS-induced neuromodulatory effects might relate to the neural correlates and be modulated by individual anatomical profiles in relation to meta-memory.Methods: In a within-subjects design, we assessed the impact of 20-min rTMS over the precuneus, compared to the vertex, across three magnetic resonance imaging (MRI) neuroprofiles on 18 healthy subjects during a memory versus a perceptual task.Results: Task-based functional MRI revealed that BOLD signal magnitude in the precuneus is associated with variation in individual meta-memory efficiency, and such correlation diminished significantly following TMS targeted at the precuneus. Moreover, individuals with higher resting-state functional connectivity (rs-fcMRI) between the precuneus and the hippocampus, or smaller grey matter volume in the stimulated precuneal region exhibit considerably higher vulnerability to the TMS effect. These effects were not observed in the perceptual domain. Conclusion:We provide compelling evidence in outlining a possible circuit encompassing the precuneus and its mnemonic midbrain neighbor the hippocampus at the service of realizing our meta-awareness during memory recollection of episodic details.

Metacognition is the capacity to introspectively monitor and control 31 one's own cognitive processes. Previous anatomical and functional neuroimaging 32 findings implicated the important role of precuneus in metacognition processing, 33 especially during mnemonic tasks. However, the issue of whether this medial parietal 34 cortex is a domain-specific region that supports mnemonic metacognition remains 35 controversial. Here, we focally disrupted this parietal area with repetitive transcranial 36 magnetic stimulation in healthy participants of both sexes, seeking to ascertain its 37 functional necessity for metacognition for memory versus perceptual decisions. 38Perturbing the precuneal activity impaired the metacognitive efficiency selectively in 39 the memory judgment of temporal-order, but not in perceptual discrimination. 40Moreover, the correlation in individuals' metacognitive efficiency between the domains 41 disappeared when the precuneus was perturbed. Together with the previous finding that 42 lesion to the anterior prefrontal cortex impairs perceptual but not mnemonic 43 metacognition, we double dissociated the macro-anatomical underpinnings for the two 44 kinds of metacognitive capacity in an interconnected network of brain regions. 45 46 47 Mnemonic metacognition in precuneus 3 SIGNIFICANCE STATEMENT: Theories on the neural basis of metacognition have 48 thus far largely centered on the role of prefrontal cortex. Here we refined the theoretical 49 framework through characterizing a unique precuneal involvement in mnemonic 50 metacognition with a noninvasive but inferentially powerful method: transcranial 51 magnetic stimulation. By quantifying meta-cognitive efficiency across two distinct 52 domains (memory vs. perception) that are matched for stimulus characteristics, we 53 reveal an instrumentaland highly selectiverole of the precuneus in mnemonic 54 metacognition. These causal evidence corroborate ample clinical reports that parietal 55 lobe lesions often produce inaccurate self-reports of confidence in memory recollection 56 and establish that the precuneus as a nexus for the introspective ability to evaluate the 57 success of memory judgment in humans. 58 59 60 Mnemonic metacognition in precuneus 4 INTRODUCTION 61 62Metacognition is the ability to introspectively monitor and control one's own 63 cognitive processes, which is important to guide adaptive behavior, social interaction 64 and mental health (Flavell, 1979; Frith, 2012; Nelson, 1990; Teasdale et al., 2002). 65 Metacognitive capacity has been mostly assessed by self-reporting of level of 66 confidence in one's own decisions that correlate with objective performance. The initial 67 task is often called "type 1 task" and the ensuing confidence judgment task is called 68 "type 2 task" (Galvin, Podd, Drga, & Whitmore, 2003). A widely used approach to 69 estimate the metacognitive efficiency without having it confounded by the primary task 70 performance and response bias is to calculate the comparison between the type 1 71 sensitiv...

Our subjective experience of remembering guides and monitors the reconstruction of past and simulation of the future, which enables us to identify mistakes and adjust our behavior accordingly. However, it remains incompletely understood what underlies the process of subjective mnemonic experience. Here, we combined behavior, repetitive TMS, and functional neuroimaging to probe whether vividness and confidence are generated differently during retrieval. We found that preretrieval repetitive TMS targeting the left angular gyrus (AnG) selectively attenuated the vividness efficiency compared with control stimulation while keeping metacognitive efficiency and objective memory accuracy unaffected. Using trialwise data, we showed that AnG stimulation altered the mediating role of vividness in confidence in the accuracy of memory judgment. Moreover, resting-state functional connectivity of hippocampus and AnG was specifically associated with vividness efficiency, but not metacognitive efficiency across individuals. Together, these results identify the causal involvement of AnG in gauging the vividness, but not the confidence, of memory, thereby suggesting a differentiation account of conscious assessment of memory by functionally and anatomically dissociating the monitoring of vividness from confidence.