RESUMO
Disturbances in recognizing facial expressions of disgust have been reported previously in pre-symptomatic and manifest Huntington's disease. Given the substantial role of the insula and basal ganglia in the perception of disgust as revealed by functional imaging, lesion studies and intracerebral recordings, we propose dysfunction within the insula and/or basal ganglia as the underlying neural substrate. Using functional MRI (fMRI), we studied a group of nine pre-symptomatic Huntington's disease gene carriers and nine healthy controls, matched for age, gender, intelligence and years of education, while they were viewing disgusted facial expressions. As control conditions, surprised and neutral expressions were presented. Compared with healthy controls, Huntington's disease gene carriers showed reduced responses within the left dorsal anterior insula during processing of disgusted facial expressions. Moreover, processing of disgust was associated with significant activation of the left dorsal anterior insula and putamen in healthy controls, but not in Huntington's disease gene carriers. Furthermore, behavioural assessment revealed a selective impairment in recognizing facial expressions displaying disgust in Huntington's disease gene carriers. Our finding of dysfunctional decreased insula activation in pre-symptomatic Huntington's disease provides an explanation for the clinical deficit in recognizing facial expression of disgust. Furthermore, it underscores the role of the insula in the emotion of disgust.
Assuntos
Emoções , Expressão Facial , Doença de Huntington/psicologia , Transtornos da Percepção/etiologia , Adulto , Gânglios da Base/fisiopatologia , Córtex Cerebral/fisiopatologia , Feminino , Heterozigoto , Humanos , Doença de Huntington/genética , Doença de Huntington/fisiopatologia , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Reconhecimento Visual de Modelos , Transtornos da Percepção/fisiopatologia , Percepção SocialRESUMO
BACKGROUND: Deep brain stimulation (DBS) of the subthalamic nucleus (STN) improves motor signs in Parkinson's disease. However, clinical studies suggest that DBS of the STN may also affect cognitive and emotional functions. OBJECTIVE: To study the impact of STN stimulation in Parkinson's disease on perception of facial expressions. RESULTS: There was a selective reduction in recognition of angry faces, but not other expressions, during STN stimulation. CONCLUSIONS: The findings may have important implications for social adjustment in these patients.
