THE NEURAL BASIS OF METACOGNITION IN LESION MODELS

IBAÑEZ AGUSTIN; DOTTORI MARTIN; BABINO ANDRES; MANES FACUNDO; SIGMAN MARIANO; MELLONI MARGHERITA; GARCIA CORDERO, INDIRA; GARCIA ADOLFO; MARTOREL MIQUELL; SEDEÑO LUCAS

Congreso; Society for Neuroscience; 2018

Metacognition, the knowledge about own mental abilities, is strongly linked to self-control and self-awareness. While neuroscientific study on this domain has accrued in recent years, only few studies have compared metacognitive performance across brain pathologies and none has applied the lesion model approach combined with neuroimaging (MRI) analysis. To bridge this gap, we evaluated metacognition in patients with focal frontal-insular lesions (FIS) and dementias ?behavioral variant frontotemporal dementia (bvFTD) and Alzheimer?s disease (AD)?, who present damage in key metacognitive areas. Participants performed a visual perception task and provided two types of metacognitive report: confidence (judgment of trust about the performance) and wagering (betting on their accuracy in the perceptual task). Then, damaged areas were analyzed via structural MRI to identify an association with impaired metacognitive outcomes.Results showed that, relative to controls, FIS and bvFTD patients did not present differences in confidence, whereas AD patients proved significantly overconfident. In contrast, wagering performance was affected in all patient groups. MRI analysis evidenced that lesions in orbitofrontal regions were involved in overconfidence, and damage in dorsolateral regions was associated with excessive wagering. Therefore, this study allowed a differentiation between metacognitive performance (confidence vs. wagering) and pathologies (orbitofrontal lesions vs. dorsolateral lesions).The impairment of confidence and wagering in AD patients evidenced a lack of self-awareness in both types of metacognitive measures. Remarkably, in the frontal pathologies (FIS and bvFTD), confidence was preserved, but wagering was excessive, showing a failure to use metacognitive information to bet adequately. Finally, overconfidence was associated with orbitofrontal damage, while impaired wagering was related with dorsolateral lesions. These results and the application of the lesion model approach across contrastive pathologies contributed to a better understanding of the brain functions, and specifically, of the metacognitive processes.