Publications by authors named "Simeng An"

Background: The monoamine system, particularly the serotonergic neurons in the dorsal raphe nucleus (DRN), associated with the synthesis and release of 5-hydroxytryptamine, is crucial for regulating pain. The lateral habenula (LHb) modulates DRN neurons by acting through GABAergic neurons located in the rostromedial tegmental nucleus (RMTg). However, the role of RMTg in mediating the LHb and regulating pain remains unclear.

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Primary dysmenorrhea(PDM) is defined as painful menstrual cramps without any evident pathology, exhibiting central nervous system(CNS) sensitivity and functional and structural changes in brain regions responsible for pain perception and modulation. Previous imaging studies primarily focused on functional changes, with only a limited number of studies investigated changes in brain morphology, and these studies generally used small sample sizes. It remains largely unknown whether brain structural changes are coupled with functional changes in patients with PDM, as well as the association between structural alterations and prostaglandin levels.

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Partial sleep deprivation (PSD) alters neural activity of intrinsic brain networks involved in cognitive functions. However, the age-related time-varying properties of large-scale brain functional networks after PSD remain unknown. Our study applied energy landscape analysis to resting-state functional magnetic resonance imaging data to characterize the dominant brain activity patterns in 36 healthy young (19 females, 23.

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The human brain is a dynamic system that shows frequency-specific features. Neuroimaging studies have shown that both healthy individuals and those with chronic pain disorders experience pain influenced by various processes that fluctuate over time. Primary dysmenorrhea (PDM) is a chronic visceral pain that disrupts the coordinated activity of brain's functional network.

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Background: The brain in resting state has complex dynamic properties and shows frequency dependent characteristics. The frequency-dependent whole-brain dynamic changes of resting state across the scans have been ignored in Alzheimer's disease (AD).

Objective: Coactivation pattern (CAP) analysis can identify different brain states.

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Article Synopsis
  • Research identifies three key brain networks that are affected during resting states in Alzheimer's patients: the default mode network (DMN), salient network (SN), and central executive network (CEN).
  • Using an innovative method called energy landscape, the study examines how these networks function differently in Alzheimer's patients compared to healthy individuals.
  • Findings reveal that Alzheimer's patients exhibit unstable brain dynamics with heightened flexibility in state transitions, which correlates with clinical symptoms, thus shedding light on the underlying mechanisms of brain activity in the condition.
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