Amygdala response in patients with acute PTSD to masked and unmasked emotional facial expressions.

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.