Lateralization of the Aberrant Amplitude of Low-Frequency Fluctuation within the Default Mode Network in Patients with Mild Cognitive Impairment.
Yongjia Shao, Yan Li, Zijian Wang, Yan Zeng, Yu-Han Yang, Yibin Wang, Gen-lin Zong, Qian Xi
Academic Radiology 2025 DOI: 10.1016/j.acra.2024.12.073 (opens in new tab)
Study at a glance
AI-extracted from the abstract| Characteristics | Case-control imaging study Peer reviewed |
|---|---|
| Sample size | 62 |
| Population | Patients with mild cognitive impairment (n=36) and normal controls (n=26) |
| Measures | Mini-Mental State Examination, Montreal Cognitive Assessment, amplitude of low-frequency fluctuation (ALFF) |
| Topics | Default mode network |
| Key findings | The default mode network showed the most widespread local brain activity changes in patients with mild cognitive impairment, with significant lateralization of amplitude of low-frequency fluctuation (ALFF) values. The authors argue that reduced ALFF changes occur earlier than increased ones, supporting a hypothesis of cerebral functional impairment and compensation, and suggest aberrant default mode network activity might be a specific imaging marker for improving MCI diagnosis. |
Abstract
Rationale: AND OBJECTIVES Alzheimer's disease (AD) is the most common pathogenesis of dementia, and mild cognitive impairment (MCI) is considered as the intermediate stage from normal elderly to AD. Early detection of MCI is an essential step for the timely intervention of AD to slow the progression of this disease. Different form previous studies in the whole-brain spontaneous activities, this research aimed to explore the low-frequency amplitude spectrum activities of patients with MCI within the default mode network (DMN), which has been involved in the process of maintaining normal cognitive function.
Materials and Methods: Based on resting-state functional magnetic resonance imaging, the amplitude of low-frequency fluctuation (ALFF) was used to analyze alterations in brain regions. The Mini-Mental State Examination and Montreal Cognitive Assessment were used for cognitive assessments. The correlation between imaging and behavioral results was analyzed among patients with MCI (n=36) and normal controls (n=26).
Results: The DMN is the highest coverage of brain network regarding changes in local brain activity in patients with MCI. And the MCI group showed significant aberrant lateralization of the ALFF value.
Conclusion: The current results of our study has confirmed the hypothesis of cerebral functional impairment and compensation, and suggests that functional changes in the brain regions with reduced values of the ALFF occurred earlier than those with increased values. In a word, it suggested that the aberrant spontaneous brain activity in the DMN might be a specific imaging marker for improving MCI diagnoses.