Early auditory middle latency evoked potentials correlates with recovery from aphasia after stroke.

OBJECTIVE: To assess the relationship between the latency of Pa and Nb peaks of the middle latency auditory responses and the score on the Boston Diagnostic Aphasia Examination, during a 6-month follow-up after stroke in the territory of the left mid cerebral artery. METHODS: The middle latency auditory potentials of 10 aphasic stroke patients were recorded within the first 3 days post-onset, at the time of hospital discharge and 2, 4 and 6 months afterwards, along with that of 30 control subjects; in patients, the evolution of aphasia was evaluated using the Boston Diagnostic Aphasia Examination score. RESULTS: During follow-up decreasing potential latencies and increasing language scores were observed (ANCOVA, R(2) 0.75, p<0.01); the Nb peak latency recorded during the first days after stroke was related to the language score difference after 6 months (Pearson, r=0.66, p<0.01). CONCLUSIONS: In patients with aphasia after stroke, the auditory electrical response recorded at hospital discharge, after stroke is related to their recovery from aphasia, evaluated by the Boston Diagnostic Aphasia Examination. SIGNIFICANCE: Early middle latency auditory evoked responses may have a prognostic value in aphasic stroke patients.