Metacognitive and online error awareness deficits after prefrontal cortex lesions

► We measured metacognitive and online deficit awareness in focal lesion patients. ► Left and right frontal lobe lesion patients showed reduced metacognitive awareness. ► Left and right frontal lesion patients showed deficits in online error monitoring. ► Right frontal patients had particularly reduced autonomic response to aware errors. ► Metacognitive and online awareness may depend on distinct neuroanatomical areas.