Abstract: Objective To investigate the feature of event-related potential N400 before and after speech therapy in Chinese aphasia patients.Methods 20 Chinese aphasia patients received speech therapy for 12 weeks. Language function was evaluated with Western Aphasia Battery (WAB), and the latency and amplitude of N400 were monitored before and after treatment. Results Spontaneous speech, retelling,and nomination in WAB and aphasia quotient (AQ) of WAB significantly increased after treatment (P<0.05). N400 latency was shorter and N400 amplitude was lower after treatment (P<0.05). The latency and amplitude of N400 were negatively correlated to the score of AQ in the difference before and after treatment (P<0.001). Conclusion Event-related potential N400 could reflect the improvement of speech function before and after treatment, and it is a valuable index for evaluating the recovery of language function in Chinese aphasia patients.

Key words: aphasia, speech therapy, N400