Individuals with posttraumatic stress disorder (PTSD) have
been found to show several event-related brain potential (ERP)
abnormalities including reduced target P3b amplitude, P50
suppression, and P2 amplitude/intensity slope. Female Vietnam
nurse veterans with (n = 29) and without (n
= 38) current PTSD completed P50 paired-click, three-tone
“oddball” and four-tone stimulus-intensity modulation
procedures. Opposite to previous findings, the current PTSD
group had larger target P3b amplitudes and increased P2
amplitude/intensity slopes. Reduced P50 suppression was associated
with increased severity of general psychopathology, but not
with PTSD diagnosis. Findings suggest that target P3b amplitude
and P2 amplitude/intensity slope abnormalities reflect different
pathophysiological processes. Future research is needed to
determine whether the opposite ERP abnormalities observed in
this PTSD sample reflect gender-, trauma-, or sample-specific
findings.