Pragmatics, theory of mind and executive functions after a right-hemisphere lesion: Different patterns of deficits

The occurrence of a right-hemisphere lesion can interfere with pragmatic abilities, and particularly with the processing of non-literal speech acts in which the listener has to identify the speaker's intention. A few studies have shown that RHD individuals may exhibit moderate difficulties in tasks requiring attribution of second-order mental states (ToM), suggesting a link between pragmatic and ToM abilities. Although links seem to exist between pragmatic abilities, ToM and executive functions in other populations, no study had tested those three abilities in RHD individuals to explore the possible co-occurrence of impairments in these three abilities. This study evaluated pragmatic and ToM abilities and executive functions in 15 RHD individuals and 15 healthy control participants. The results suggest that the ability to understand pragmatic aspects of language is closely associated with the ability to make inferences about other people's intentions. More interestingly, the association of ToM deficits with executive dysfunction rather than executive dysfunction alone might be the best predictor of different patterns of pragmatic deficits found in different RHD subgroups of patients.