Authors
- Lew, Henry L. MD, PhD
- Gray, Max BA
- Poole, John H. PhD
- Salerno, Rose Marie RN
Article Content
Objectives: Prior research has examined cognitive Event-related Potential (ERP) waveforms in either healthy individuals or patients with traumatic brain injury (TBI), but the reliability of these measures over time has not been systematically evaluated. Hypothesis: We predicted that early components would be reliable over time for both groups and later components would be more variable across time. Participants: Sixteen healthy controls and 6 patients with moderate to severe TBI. Methods: We examined the middle and late ERP components to stimuli in an auditory oddball task. Subjects were retested 7 to 10 days later. Results: The N1 was stable across time in both groups. Later components differed. Controls produced typical ERP waveforms at both times. The TBI patients' P3 to rare target stimuli were reliable across time. The TBI group produced an atypical P3-like response to nontarget stimuli, with an increase at time 2. The N4 to rare stimuli showed a reduction across time in the controls but not the TBI group. Conclusions: This pattern suggests that the N4 component may reflect carryover learning, which is typically impaired in TBI patients. Together, these findings indicate that the later ERP components can reliably measure higher order cognitive processing in healthy individuals and TBI patients.
REFERENCES
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