Differential Impairments in Irony comprehension in Brain-Damaged Individuals: Insight from contextual processing, theory of mind, and executive functions

Objective: The comprehension of irony can be affected after brain injuries. The cognitive mechanisms
accounting for such disorders remain yet unclear. The heterogeneity of cognitive profiles of braindamaged
individuals and the use of independent tests to measure the links between these mechanisms and
the comprehension of irony might contribute to this lack of clarity. The present study aimed to further
explore the underlying mechanisms of irony-understanding disorders (i.e., context processing, executive
functions [EF], and theory of mind [ToM]) in patients with brain lesions. Method: We used a paradigm
manipulating these mechanisms within an irony task to identify different patterns of pragmatic performance
associated with cognitive profiles. We administered this task and standard neuropsychological
tests assessing EF and ToM to 30 participants with acquired brain injury (ABI) and 30 healthy control
(HC) participants. Results: A cluster analysis revealed that two thirds of the participants with ABI (3
subgroups out of 4) presented atypical pragmatic and neuropsychological patterns. The most severe
disturbances in understanding irony, characterized by insensitivity to the context, were associated with
a joint impairment of ToM and EF in 1 subgroup. In the 2 other context-sensitive subgroups, an isolated
deficit in EF co-occurred with difficulties dealing with literal or ironic statements when the EF demand
of the irony task was increased. However, the effect of this EF demand could be negated by the presence
of markers helping the comprehension of irony. Conclusion: These results have important clinical
implications for the evaluation and therapy of pragmatic disorders in individuals with ABI.