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This study's objectives were to characterize the frequency and profile of behavioral and cognitive dysexecutive syndromes in patients with focal prefrontal cortex damage and how these syndromes overlap. We also examined the contribution of the prefrontal brain regions to these syndromes. Therefore, thirty patients with prefrontal cortex damage and thirty control subjects were compared on their performances using the GREFEX battery assessing the dysexecutive syndromes. The results showed that combined behavioral and cognitive dysexecutive syndrome was observed in 53.33%, while pure cognitive dysexecutive syndrome was observed in 20% and behavioral in 26.67%. Also, almost all behavioral and cognitive dysexecutive disorders discriminated frontal patients from controls. Moreover, correlations and regression analyses between task scores in both domains of dysexecutive syndromes showed that the spectrum of behavioral disorders was differentially associated with cognitive impairment of initiation, inhibition, generation, deduction, coordination, flexibility and the planning process. Furthermore, the patterns of cognitive and behavioral dysexecutive syndrome were both predictors of impairment in daily living activities and loss of autonomy. Finally, frontal regions contributing to different dysexecutive syndromes assessed by MRI voxel lesion symptom analysis indicate several overlapping regions centered on the ventromedial and dorsomedial prefrontal cortex for both domains of dysexecutive syndrome. This study concludes that damage to the frontal structures may lead to a diverse set of changes in both cognitive and behavioral domains which both contribute to loss of autonomy. The association of the ventromedial and dorsomedial prefrontal regions to both domains of dysexecutive syndrome suggests a higher integrative role of these regions in processing cognition and behavior. [ABSTRACT FROM AUTHOR]

Few studies have examined the specific contribution of focal damage of the prefrontal cortex and executive dysfunction to emotion recognition deficits, with results reporting controversial findings. This study investigated the performance of 30 patients with prefrontal cortex damage and 30 matched controls on a battery of executive measures assessing processes of inhibition, flexibility, and planning and a task of emotion recognition with also a particular attention to the examination of the association between these domains. The results showed that compared with control participants, patients with prefrontal cortex damage were impaired in recognizing the three negative emotions of fear, sadness, and anger and were also impaired on all executive measures. Moreover, by examining the association between both these domains, using correlation and regression analyses, we noted that impaired performance in recognizing emotions of fear, sadness, and anger was predicted by impaired performances on the measures of inhibition and flexibility or "set-shifting" suggesting that the ability to recognize emotions could be at least to some extent cognitively mediated. Finally, using a voxel-based lesion technique, we identified a partially common prefrontal network underlying deficits on executive functions and emotions recognition centered on the ventral and medial parts of the prefrontal cortex, reflecting beyond the neural network involved in recognizing negative emotions per se that of the cognitive processes elicited by this emotion task. [ABSTRACT FROM AUTHOR]

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. 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. 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. These findings suggest that the ability to read mental states of mind depends on the inhibition and flexibility executive mechanisms. [ABSTRACT FROM AUTHOR]