The role of the amygdala in facial emotion recognition in schizophrenia

Abstract:

OBJECTIVE: To provide an update on knowledge of the functions of the amygdala in healthy individuals and schizophrenics, with special emphasis on the process of facial emotion recognition. DEVELOPMENT: The amygdala plays a key role in danger evaluation, including possible external aggressions, novelty in general and especially external stimuli that could pose a threat to survival. Consequently, the amygdala is activated in healthy individuals during facial emotion recognition, acting as a warning sign activator. Patients with schizophrenia have severe emotional difficulties and consequently the amygdala has long been considered a critical structure in investigation of this disorder. To date, structural alterations have been found in the amygdalae of schizophrenic patients, while the findings of functional neuroimaging tests have been much more contradictory, including hypo-, hyper-and normal activation, suggesting overall dysfunction. CONCLUSIONS: The results obtained to date could be due to a deficiency in the amygdalar habituation mechanism in patients with schizophrenia or to the heterogeneity of the disorder. Studies with more homogeneous samples should be performed and different study models are proposed.