Brain networks functional connectivity (FC) (FC)

Brain networks functional connectivity (FC) refers to the statistical temporal correlation between neurophysiological signals originating from anatomically distinct regions of the brain (PLOS Computational Biology, 2012). Unlike structural connectivity, which maps physical axonal pathways, functional connectivity reflects the degree of synchronized activity and information flow between neural populations, often organized into large-scale "resting-state networks" such as the Default Mode Network (DMN), Executive Control Network (ECN), and Salience Network (PubMed, 2025). It is a systems-level property essential for complex biological functions, including executive control, memory consolidation, and emotional processing (MDPI, 2024). Dysregulation of these connectivity patterns is a hallmark of various neurological and psychiatric disorders; for instance, Major Depressive Disorder is often associated with DMN hyperactivity, while Alzheimer’s disease is characterized by network fragmentation and reduced global efficiency (PMC, 2018). While not a classical molecular target like a receptor or enzyme, functional connectivity serves as a critical biomarker and a "systemic target" for pharmacological interventions—such as Ketamine or Donepezil—and neuromodulation techniques like Repetitive Transcranial Magnetic Stimulation (rTMS) that aim to restore healthy brain network dynamics by altering neurotransmitter balance and synaptic plasticity (Neurology Today, 2024).

Other names

Resting-state functional connectivityIntrinsic brain connectivityNeural network synchronyRSFCLarge-scale functional connectivityFunctional brain network topology

Modulation of synaptic weights and neurotransmitter concentrations (e.g., glutamate, GABA, and serotonin) to shift the temporal synchronization and coherence of large-scale neural oscillators across spatially distant brain regions.