Objective
To verify the correlation between auditory event-related potential and Cognitive Capacity Screening Examination (CCSE) in patients with brain lesion.

Method
P300 study using an auditory paradigm was performed in thirty patients with brain lesion, age ranged from thirteen to seventy-three years-old, and then was compared with the score of CCSE.

Results
The mean latency of P300 was 383.07⁑50.63 msec. The mean score of CCSE was 17.10⁑8.62. There was no significant difference in P300 latency and score of CCSE between male and female, and among the types of brain lesion. There was significant negative correlation between P300 latency and score of CCSE (p＜0.05, r=⁣0.686), between score of CCSE and age (p＜0.05, r=⁣0.364). There was significantly high intra-rater reliability in P300 latency study (alpha=0.9771).

Conclusion
We conclude that P300 electrodiagnostic study is useful for reflection of cognitive function in patients with brain lesion.