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Frequency-dependent changes in the regional amplitude and synchronization of resting-state functional MRI in stroke.

Zhu J, Jin Y, Wang K, Zhou Y, Feng Y, Yu M, Jin X - PLoS ONE (2015)

Bottom Line: Both the ALFF and ReHo analyses revealed changes in brain activity in a number of brain regions, particularly the parietal cortex, in stroke patients compared with healthy controls.Remarkably, the regions with changed activity as detected by the slow-5 band data were more extensive, and this finding was true for both the ALFF and ReHo analyses.These results not only confirm previous studies showing abnormality in the parietal cortex in patients with stroke, but also suggest that R-fMRI studies of stroke should take frequency effects into account when measuring intrinsic brain activity.

View Article: PubMed Central - PubMed

Affiliation: Department of Acupuncture and Moxibustion, Zhejiang Hospital, Number 12, Lingyin Road, Xihu District, Hangzhou, China.

ABSTRACT
Resting-state functional magnetic resonance imaging (R-fMRI) has been intensively used to assess alterations of inter-regional functional connectivity in patients with stroke, but the regional properties of brain activity in stroke have not yet been fully investigated. Additionally, no study has examined a frequency effect on such regional properties in stroke patients, although this effect has been shown to play important roles in both normal brain functioning and functional abnormalities. Here we utilized R-fMRI to measure the amplitude of low-frequency fluctuations (ALFF) and regional homogeneity (ReHo), two major methods for characterizing the regional properties of R-fMRI, in three different frequency bands (slow-5: 0.01-0.027 Hz; slow-4: 0.027-0.73 Hz; and typical band: 0.01-0.1 Hz) in 19 stroke patients and 15 healthy controls. Both the ALFF and ReHo analyses revealed changes in brain activity in a number of brain regions, particularly the parietal cortex, in stroke patients compared with healthy controls. Remarkably, the regions with changed activity as detected by the slow-5 band data were more extensive, and this finding was true for both the ALFF and ReHo analyses. These results not only confirm previous studies showing abnormality in the parietal cortex in patients with stroke, but also suggest that R-fMRI studies of stroke should take frequency effects into account when measuring intrinsic brain activity.

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Related in: MedlinePlus

Relationships between ALFF and ReHo for regions showing abnormal ALFF and ReHo in patients.Significantly negative correlations were found between these two measures in stroke patients.
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pone.0123850.g003: Relationships between ALFF and ReHo for regions showing abnormal ALFF and ReHo in patients.Significantly negative correlations were found between these two measures in stroke patients.

Mentions: We found that several regions simultaneously exhibited abnormalities of decreased ALFF and increased ReHo in patients compared with healthy controls. Thus, we further examined the relationships between ALFF and ReHo for these regions in the patients. As shown in Fig 3, significant negative correlations were found between these two measures in stroke patients.


Frequency-dependent changes in the regional amplitude and synchronization of resting-state functional MRI in stroke.

Zhu J, Jin Y, Wang K, Zhou Y, Feng Y, Yu M, Jin X - PLoS ONE (2015)

Relationships between ALFF and ReHo for regions showing abnormal ALFF and ReHo in patients.Significantly negative correlations were found between these two measures in stroke patients.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4401774&req=5

pone.0123850.g003: Relationships between ALFF and ReHo for regions showing abnormal ALFF and ReHo in patients.Significantly negative correlations were found between these two measures in stroke patients.
Mentions: We found that several regions simultaneously exhibited abnormalities of decreased ALFF and increased ReHo in patients compared with healthy controls. Thus, we further examined the relationships between ALFF and ReHo for these regions in the patients. As shown in Fig 3, significant negative correlations were found between these two measures in stroke patients.

Bottom Line: Both the ALFF and ReHo analyses revealed changes in brain activity in a number of brain regions, particularly the parietal cortex, in stroke patients compared with healthy controls.Remarkably, the regions with changed activity as detected by the slow-5 band data were more extensive, and this finding was true for both the ALFF and ReHo analyses.These results not only confirm previous studies showing abnormality in the parietal cortex in patients with stroke, but also suggest that R-fMRI studies of stroke should take frequency effects into account when measuring intrinsic brain activity.

View Article: PubMed Central - PubMed

Affiliation: Department of Acupuncture and Moxibustion, Zhejiang Hospital, Number 12, Lingyin Road, Xihu District, Hangzhou, China.

ABSTRACT
Resting-state functional magnetic resonance imaging (R-fMRI) has been intensively used to assess alterations of inter-regional functional connectivity in patients with stroke, but the regional properties of brain activity in stroke have not yet been fully investigated. Additionally, no study has examined a frequency effect on such regional properties in stroke patients, although this effect has been shown to play important roles in both normal brain functioning and functional abnormalities. Here we utilized R-fMRI to measure the amplitude of low-frequency fluctuations (ALFF) and regional homogeneity (ReHo), two major methods for characterizing the regional properties of R-fMRI, in three different frequency bands (slow-5: 0.01-0.027 Hz; slow-4: 0.027-0.73 Hz; and typical band: 0.01-0.1 Hz) in 19 stroke patients and 15 healthy controls. Both the ALFF and ReHo analyses revealed changes in brain activity in a number of brain regions, particularly the parietal cortex, in stroke patients compared with healthy controls. Remarkably, the regions with changed activity as detected by the slow-5 band data were more extensive, and this finding was true for both the ALFF and ReHo analyses. These results not only confirm previous studies showing abnormality in the parietal cortex in patients with stroke, but also suggest that R-fMRI studies of stroke should take frequency effects into account when measuring intrinsic brain activity.

Show MeSH
Related in: MedlinePlus