18FDG PET study of amygdalar activity during facial emotion recognition in schizophrenia

The role of the amygdala during facial emotion recognition (FER) tasks as well as its clinical implications in schizophrenia patients remains unclear. While most of authors have reported hypoactivation, recently it has been suggested that patients may also exhibit hyperactivation. We studied amygdalar response during a previously validated FER task using 18[F] fluorodeoxyglucose positron emission tomography (18FDG-PET) technique in ten right-handed healthy volunteers and 11 right-handed non acute patients with schizophrenia. Both groups underwent two scans on different days in a random order; each consisted of 17 1/2 min of continuous emotional and control tasks. Statistical Parametric Mapping (SPM) 2 analysis with a region of interest approach was carried out. Left amygdalar hyperactivation among the schizophrenia group was shown in both emotional and control tasks when compared to healthy subjects. The right amygdala showed no differential activation in any of the tasks. Patients diagnosed with schizophrenia exhibit a non-task specific amygdalar hyperactivation during a continuous emotional and non-emotional task when compared to matched healthy controls.