Automatic amygdala response to facial expression in schizophrenia: initial hyperresponsivity followed by hyporesponsivity

摘要

Background It is well established that the amygdala is crucially involved in the processing of facial emotions. In schizophrenia patients, a number of neuroimaging findings suggest hypoactivation of the amygdala in response to facial emotion, while others indicate normal or enhanced recruitment of this region. Some of this variability may be related to the baseline condition used and the length of the experiment. There is evidence that schizophrenia patients display increased activation of the amygdala to neutral faces and that this is predominantly observed during early parts of the experiment. Recent research examining the automatic processing of facial emotion has also reported amygdala hyperactivation in schizophrenia. In the present study, we focused on the time-course of amygdala activation during the automatic processing of emotional facial expression. We hypothesized that in comparison to healthy subjects, patients would initially show hyperresponsivity of the amygdala to masked emotional and neutral faces. In addition, we expected amygdala deactivation in response to masked facial emotions from the first to the second phase to be more pronounced in patients than in controls.