RESUMEN
OBJECTIVE: This study used functional magnetic resonance imaging to investigate amygdala response in patients with acute posttraumatic stress disorder (PTSD) to emotional expressions. METHOD: Thirteen medication-free individuals with acute PTSD and no axis I psychiatric comorbidity were scanned while viewing pictures of fearful or happy faces, presented above or below consciousness, with backward masking. RESULTS: There was a significant positive correlation between the severity of PTSD and the difference in amygdala responses between masked fearful and happy faces and a corresponding negative correlation for the difference between unmasked fearful and happy faces. CONCLUSIONS: These findings suggest that functional abnormalities in brain responses to emotional stimuli observed in chronic PTSD are already apparent in its acute phase.
Asunto(s)
Amígdala del Cerebelo/fisiopatología , Emociones/fisiología , Expresión Facial , Enmascaramiento Perceptual/fisiología , Percepción Social , Trastornos por Estrés Postraumático/diagnóstico , Enfermedad Aguda , Adulto , Mapeo Encefálico , Miedo/fisiología , Miedo/psicología , Femenino , Lateralidad Funcional/fisiología , Felicidad , Humanos , Imagen por Resonancia Magnética/estadística & datos numéricos , Masculino , Persona de Mediana Edad , Índice de Severidad de la Enfermedad , Trastornos por Estrés Postraumático/fisiopatología , Trastornos por Estrés Postraumático/psicologíaRESUMEN
BACKGROUND: Two studies found morphological differences in the anterior cingulate cortex (ACC) of individuals with chronic posttraumatic stress disorder (PTSD). We sought to replicate and extend these findings in a sample of individuals with acute PTSD. METHODS: The ACCs of individuals with acute PTSD (n = 14) and matched healthy control subjects (n = 14) were compared using voxel-based morphometry (VBM), semi-automated volumetric analyses, and probabilistic maps. Posttraumatic stress disorder diagnosis was ascertained by a psychologist using a structured interview. RESULTS: Voxel-based morphometry analyses revealed significantly less gray-matter density in the right pregenual ACC and in the left insula of the PTSD group. However, volumetric analyses of the ACC revealed no significant differences between groups. Probabilistic maps of the labels of the pregenual ACC indicated that the difference between groups in gray matter density was due to shape differences. CONCLUSIONS: Although there are no volumetric differences in the ACC of acute PTSD individuals compared with normal control subjects, significant shape differences exist, which might indicate volumetric differences in the surrounding structures.