Faux pas deficits in people with medial frontal lesions as related to impaired understanding of a speaker's mental state.

This study examined the nature of deficits in mentalizing, the ability to read the mental state of other people, as measured by a faux pas task in people with medial frontal lesions. A total of 56 Mandarin-speaking Chinese individuals participated (9 participants with medial frontal lesions, 12 participants with lateral frontal lesions, 5 participants with non-frontal lesions, and 30 healthy controls). The faux pas test ascertained the participants' ability to identify and understand a social faux pas, and to understand the mental states of the characters (the speaker and the recipient in a conversation with a social faux pas). Although the participants with medial frontal lesions performed less well than the other clinical participants and the control participants on all aspects of the faux pas test, the most significant deficit was observed in understanding mental states and hence inferring the speaker's intentions. The performance on the various aspects of decoding a social faux pas by people with medial frontal lesions suggests that the cognitive processes, and hence the respective neural correlates subserving these various processes, may be different. Our results add to existing literature and illustrate the very nature of deficits of mentalizing, measured by a faux pas test, experienced by people with medial frontal lesions. The data have also prompted that future behavioral and neuroimaging studies may be applied to further decode both the neural mechanisms and the cognitive variables affecting "mentalizing".