Primary objective: To compare P300 source analysis with conventional analysis in patients with cognitive impairment after brain injury.
Methods and procedures: P300 results were compared with neuropsychological test data and imaging data in 21 healthy control subjects and 33 patients with brain injury. Latency and amplitude parameters were obtained for both P300 analysis methods. Magnetic Resonance Imaging (MRI) was performed between 3-12 months after the injury.
Main outcomes and results: For both P300 analysis methods, only amplitude parameters correlated with neuropsychological test data. Diagnostic accuracy was better with source analysis than conventional analysis, when compared to the VLT (p = 0.03) and the PASAT (p = 0.04, only for those patients with imaging abnormalities). Patients with normal MRI results and patients with MRI abnormalities had decreased mean P3A amplitude compared to controls. In patients with focal frontal or temporal injury, the presence of mediofrontal lesions was associated with P3A amplitude reduction, while orbitofrontal lesions tended to increase P3A amplitude.
Conclusions: Source analysis of P300 resulted in improved detection of neuropsychological abnormality in patients with brain injury. It is advisable to analyse P300 results in conjunction with imaging results. This approach may further facilitate the interpretation and diagnostic applicability of source analysis P300 results in patients with brain injury.