A CNV-distraction paradigm in combat veterans with posttraumatic stress disorder.
Fourteen veterans with posttraumatic stress disorder (PTSD) and 14 without PTSD participated in a contingent negative variation (CNV)-distraction paradigm. Subjects were instructed to press a button after hearing a high-pitched tone (S2) preceded by a low-pitched tone (S1). One-half of the trials included a white-noise distracter placed in the S1-S2 interval. Posttraumatic stress disorder subjects had larger frontal, but smaller central and parietal CNVs, regardless of condition (distracter, no distracter) or epoch (early CNV, late CNV). In PTSD subjects, the N1/P2 complex was smaller to warning (S1) and distracter stimuli and did not show the extent of facilitation present in non-PTSD subjects. Findings highlight PTSD-related differences in phasic cortical excitability and attention.
School of Psychology, University of Wales, Bangor, United Kingdom. M.Kimble@bangor.ac.uk
Matthew
M
Kimble
Kathryn
K
Ruddy
Patricia
P
Deldin
Milissa
M
Kaufman
D000161:Acoustic Stimulation; D000704:Analysis of Variance; D001288:Attention; D003130:Combat Disorders / Q000503:physiopathology*; D003265:Contingent Negative Variation / Q000502:physiology*; D004569:Electroencephalography; D005072:Evoked Potentials, Auditory; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D010897:Pitch Discrimination; D011597:Psychomotor Performance; D011930:Reaction Time; D013313:Stress Disorders, Post-Traumatic / Q000503:physiopathology*; D014728:Veterans