Objective: Conflicting evidence has arisen from the few correlational studies that have examined the relationship between the ability to decode social emotional cues through the eyes and executive functions in individuals with prefrontal cortex damage. The objective of the current study was (1) to investigate the impact of both focal prefrontal and parietal cortex damage on both of these domains; (2) to examine whether impaired ability to decode social emotion cues through the eyes was predicted by executive function deficits and; (3) to explore the neural correlates of both of these components.
Method: Thirty individuals with prefrontal cortex damage, 15 individuals with parietal cortex damage and 30 matched healthy comparison subjects were subjected to a battery of executive tasks assessing inhibition, flexibility, and planning processes and the Reading the Mind in the Eyes Task (RMET) assessing ability to decode social emotion cues through the eyes.
Results: Compared to both comparison groups, individuals with prefrontal cortex damage were impaired in performing RMET and almost all executive tasks. Regression analysis showed that for individuals with prefrontal cortex damage, performance on the Stroop and Hayling tasks predicted scores on the RMET, while for the healthy comparison group, only the verbal fluency performance predicted scores on the RMET. The Voxel lesions-symptom mapping technique showed that both components rely partly on the same neural substrates, reflecting beyond the neural network of RMET per se that of the cognitive processes elicited by this multi-determinant task.
Conclusion: These findings suggest that the ability to read mental states of mind depends on the inhibition and flexibility executive mechanisms.
Keywords: Reading The Mind In The Eyes Task; Theory of mind; executive functions; prefrontal cortex; voxel-lesion symptoms mapping.