Confidence in visual detection, familiarity and recollection judgments is preserved in schizophrenia spectrum disorder.

An effective way to quantify metacognitive performance is to ask participants to estimate their confidence in the accuracy of their response during a cognitive task. A recent meta-analysis1 raised the issue that most assessments of metacognitive performance in schizophrenia spectrum disorders may be confounded with cognitive deficits, which are known to be present in this population. Therefore, it remains unclear whether the reported metacognitive deficits are metacognitive in nature or rather inherited from cognitive deficits. Arbitrating between these two possibilities requires equating task performance between experimental groups. Here, we aimed to characterize metacognitive performance among individuals with schizophrenia across three tasks (visual detection, familiarity, recollection) using a within-subject design while controlling experimentally for intra-individual task performance and statistically for between-subject task performance. In line with our hypotheses, we found no metacognitive deficit for visual detection and familiarity judgments. While we expected metacognition for recollection to be specifically impaired among individuals with schizophrenia, we found evidence in favor of an absence of a deficit in that domain also. We found no specific metacognitive deficit in schizophrenia spectrum disorder in the visual or memory domain. The clinical relevance of our findings is discussed in light of a hierarchical framework of metacognition.

Preserved electrophysiological markers of confidence in schizophrenia spectrum disorder.

A large number of behavioral studies suggest that confidence judgments are impaired in schizophrenia, motivating the search for neural correlates of an underlying metacognitive impairment. Electrophysiological studies suggest that a specific evoked response potential reflecting performance monitoring, namely the error-related negativity (ERN), is blunted in schizophrenia compared to healthy controls. However, attention has recently been drawn to a potential confound in the study of metacognition, namely that lower task-performance in schizophrenia compared to healthy controls involves a decreased index of metacognitive performance (where metacognitive performance is construed as the ability to calibrate one's confidence relative to response correctness), independently of metacognitive abilities among patients. Here, we assessed how this confound might also apply to ERN-blunting in schizophrenia. We used an adaptive staircase procedure to titrate task-performance on a motion discrimination task in which participants (N = 14 patients and 19 controls) had to report their confidence after each trial while we recorded high density EEG. Interestingly, not only metaperceptual abilities were preserved among patients at the behavioral level, but contrary to our hypothesis, we also found no electrophysiological evidence for altered EEG markers of performance monitoring. These results bring additional evidence suggesting an unaltered ability to monitor perceptual performance on a trial by trial basis in schizophrenia.

Metacognitive improvement: Disentangling adaptive training from experimental confounds.

Metacognition is defined as the capacity to monitor and control one's own cognitive processes. Recently, Carpenter and colleagues (2019) reported that metacognitive performance can be improved through adaptive training: healthy participants performed a perceptual discrimination task, and subsequently indicated confidence in their response. Metacognitive performance, defined as how much information these confidence judgments contain about the accuracy of perceptual decisions, was found to increase in a group of participants receiving monetary reward based on their confidence judgments over hundreds of trials and multiple sessions. By contrast, in a control group where only perceptual performance was incentivized, metacognitive performance remained constant across experimental sessions. We identified two possible confounds that may have led to an artificial increase in metacognitive performance, namely the absence of reward in the initial session and an inconsistency between the reward scheme and the instructions about the confidence scale. We thus conducted a preregistered conceptual replication where all sessions were rewarded and where instructions were consistent with the reward scheme. Critically, once these two confounds were corrected we found moderate evidence for an absence of metacognitive training. Our data thus suggest that previous claims about metacognitive training are premature, and calls for more research on how to train individuals to monitor their own performance. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Systematic review and meta-analysis of metacognitive abilities in individuals with schizophrenia spectrum disorders.

Metacognitive deficits are well documented in schizophrenia spectrum disorders as a decreased capacity to adjust confidence to performance in a cognitive task. Because metacognitive ability directly depends on task performance, metacognitive deficits might be driven by lower task performance among patients. To test this hypothesis, we conducted a Bayesian meta-analysis of 42 studies comparing metacognitive abilities in 1425 individuals with schizophrenia compared to 1256 matched controls. We found a global metacognitive deficit in schizophrenia (g = -0.57, 95 % CrI [-0.72, -0.43]), which was driven by studies which did not control task performance (g = -0.63, 95 % CrI [-0.78, -0.49]), and inconclusive among controlled-studies (g = -0.23, 95 % CrI [-0.60, 0.16], BF01 = 2.2). No correlation was found between metacognitive deficit and clinical features. We provide evidence that the metacognitive deficit in schizophrenia is inflated due to non-equated task performance. Thus, efforts should be made to develop experimental protocols accounting for lower task performance in schizophrenia.