title: Amplitude of low-frequency oscillations in first-episode, treatment-naive patients with major depressive disorder: a resting-state functional MRI study.
abstract: BACKGROUND
  Resting-state fMRI is a novel approach to measure spontaneous brain activity in patients with major depressive disorder (MDD). Although most resting-state fMRI studies have focused on the examination of temporal correlations between low-frequency oscillations (LFOs), few studies have explored the amplitude of these LFOs in MDD. In this study, we applied the approaches of amplitude of low-frequency fluctuation (ALFF) and fractional ALFF to examine the amplitude of LFOs in MDD.
  
  
  RESULTS
  A total of 36 subjects, 18 first-episode, treatment-naive patients with MDD matched with 18 healthy controls (HCs) completed the fMRI scans. Compared with HCs, MDD patients showed increased ALFF in the right fusiform gyrus and the right anterior and posterior lobes of the cerebellum but decreased ALFF in the left inferior temporal gyrus, bilateral inferior parietal lobule, and right lingual gyrus. The fALFF in patients was significantly increased in the right precentral gyrus, right inferior temporal gyrus, bilateral fusiform gyrus, and bilateral anterior and posterior lobes of the cerebellum but was decreased in the left dorsolateral prefrontal cortex, bilateral medial orbitofrontal cortex, bilateral middle temporal gyrus, left inferior temporal gyrus, and right inferior parietal lobule. After taking gray matter (GM) volume as a covariate, the results still remained.
  
  
  CONCLUSIONS
  These findings indicate that MDD patients have altered LFO amplitude in a number of regions distributed over the frontal, temporal, parietal, and occipital cortices and the cerebellum. These aberrant regions may be related to the disturbances of multiple emotion- and cognition-related networks observed in MDD and the apparent heterogeneity in depressive symptom domains. Such brain functional alteration of MDD may contribute to further understanding of MDD-related network imbalances demonstrated in previous fMRI studies.
authors.affiliation: Institute of Mental Health, Peking University, Beijing, China.
authors.forename: Li
authors.initials: L
authors.lastname: Wang
authors.forename: Wenji
authors.initials: W
authors.lastname: Dai
authors.forename: Yunai
authors.initials: Y
authors.lastname: Su
authors.forename: Gang
authors.initials: G
authors.lastname: Wang
authors.forename: Yunlong
authors.initials: Y
authors.lastname: Tan
authors.forename: Zhen
authors.initials: Z
authors.lastname: Jin
authors.forename: Yawei
authors.initials: Y
authors.lastname: Zeng
authors.forename: Xin
authors.initials: X
authors.lastname: Yu
authors.forename: Wei
authors.initials: W
authors.lastname: Chen
authors.forename: Xiaodong
authors.initials: X
authors.lastname: Wang
authors.forename: Tianmei
authors.initials: T
authors.lastname: Si
mesh_terms: D000328:Adult; D001921:Brain / Q000473:pathology / Q000503:physiopathology*; D001931:Brain Mapping; D002531:Cerebellum / Q000473:pathology / Q000503:physiopathology; D003865:Major Depressive Disorder / Q000473:pathology / Q000503:physiopathology*; D005260:Female; D005625:Frontal Lobe; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D009010:Monte Carlo Method; D009778:Occipital Lobe / Q000473:pathology / Q000503:physiopathology; D010296:Parietal Lobe / Q000473:pathology / Q000503:physiopathology; D012146:Rest / Q000502:physiology*; D012720:Severity of Illness Index; D013702:Temporal Lobe / Q000473:pathology / Q000503:physiopathology; D055815:Young Adult