Frequency-dependent Alterations in Amplitude of Low-frequency Fluctuations in Resting-state Functional Magnetic Resonance Imaging of Post Stroke Aphasia / 中国康复理论与实践

ABSTRACT

Objective:To explore the characteristics of local brain neural activity in post stroke aphasia (PSA) patients in different frequency bands and the relationship between Western Aphasia Battery (WAB) scores and specific frequency bands. Methods:From March, 2015 to May, 2018, 15 PSA patients, and 15 healthy adults as controls matched for age, gender and education were recruited. They were assessed with WAB and scaned with resting-state functional magnetic resonance imaging. The amplitude of low-frequency fluctuation (ALFF) and fractional amplitude of low-frequency fluctuation (fALFF) on the frequency bands of 0.01-0.08 Hz, 0.027-0.073 Hz, and 0.01-0.027 Hz were calculated. The ALFF and fALFF in different frequency bands were extracted and the correlation with the WAB scores in the patients were analyzed. Results:On 0.01-0.08 Hz, ALFF increased in the right precentral gyrus in the patients. On 0.027-0.073 Hz, ALFF increased values in the right precentral gyrus, and fALFF decreased in the right cerebellar Crus2 region; fALFF in the right cerebellar Crus2 region negatively correlated with the scores of information content (r = -0.576, P = 0.025), auditory comprehension (r = -0.658, P = 0.008), repetition (r = -0.616, P = 0.014) and aphasia quotient (r = -0.611, P = 0.016) of WAB. On 0.01-0.027 Hz, the fALFF decreased in the left inferior parietal limbic gyrus, and positively correlated with the scores of information content (r = 0.538, P = 0.039) and aphasia quotient (r = 0.526, P = 0.044). Conclusion:Resting-state fALFF abnormalities in PSA patients are frequency-dependent, which associate with some frequency-specific neurofunctional alterations.