Abstract Dysfunction in default mode network (DMN) connectivity plays a role in the etiology and maintenance of insomnia symptoms. Negative self-referential thinking is a perpetuating factor of insomnia that has been linked with DMN connectivity. The Bed Nucleus of the Stria Terminalis (BNST), part of the extended-amygdala pathway, facilitates cognitive and physiological hyperarousal. We...
The afferent vagus nerve transmits interoceptive signals to the brain but a systematic understanding of how vagal signals affect brain-wide neuronal dynamics remains elusive. Here, comprehensive spatiotemporal analyses across the entire mouse brain revealed that vagus nerve stimulation activated neuronal ensembles within the default mode network (DMN). In contrast, vagal-independent mechanisms...
Haueis and Colaço distinguish evaluative and generative roles for metabolic considerations in cognitive modeling. I extend this framework to the default mode network, arguing that this network's elevated aerobic glycolysis constitutes a metabolic constraint on spontaneous thought. This constraint shapes the richness of spontaneous thought across varying task demands and predicts load-dependent...
The neural mechanisms underlying spontaneous perceptual switches during bistable perception, particularly the dynamic interplay between large-scale brain networks, remain incompletely understood. Here, using functional magnetic resonance imaging (fMRI) in six participants and a bistable kinetic depth effect (KDE) stimulus, we investigated the spatiotemporal dynamics of brain activity associated...
Background: Chronic pain is understood as a disturbance of large-scale brain-network organization involving systems that coordinate internally and externally oriented processing. In knee osteoarthritis (KOA), altered connectivity involving attention networks and the default mode network (DMN) has been reported, but directed organization and reconfiguration during non-noxious somatosensory input...
The human brain's ability to form and maintain rich internal representations of personally familiar others, even in the absence of direct sensory input, is a prominent feature of social cognition. We tested whether the identity of familiar individuals can be decoded from neural activity patterns elicited during internally generated reflection. Using a round-robin fMRI design (N = 113; 20 groups...
Understanding the neurobiological mechanisms underlying self-referential cognition and baseline self-consciousness remains a fundamental challenge in computational neuroscience. In this work, we propose a large-scale computational model incorporating a 10,000-neuron spiking neural network (SNN) based on Izhikevich dynamics. The network is structured into two interacting subsystems: a sensory...
medRxivSeptember 23, 2026Kevin J. Clancy, Boyu Ren, Isabelle M. Rosso
preprint
Trauma-related intrusive memories (TRIMs) are a core symptom of posttraumatic stress disorder and cause significant distress and impairment for trauma-exposed individuals due to their vivid sensory features that intrude on ongoing thought. These phenomenological properties point to a neuropathology that spans autobiographical memory, spontaneous thought, and sensory perception. The hierarchical...
Type 2 diabetes mellitus-associated cognitive dysfunction (T2DACD) is strongly linked to disruption of cognition-supporting brain networks. Electroacupuncture (EA) has increasingly been examined as a nonpharmacological intervention targeting cognitive impairment; however, the longitudinal neurobiological patterns accompanying EA in T2DACD have not been fully characterized. In this exploratory...
Antidepressant treatments, including conventional antidepressants and (es)ketamine, may reverse default mode network (DMN) resting-state functional connectivity (rsFC) alterations related to major depressive disorder (MDD). Despite these agents having distinct initial action mechanisms, both likely share downstream effects that lead to structural and functional adaptations in MDD-related neural...
Objectives: We investigate the relationship between the loss of consciousness (LOC) and the state of default mode network (DMN) connectivity in diffuse axonal injury (DAI) patients, using diffusion tensor tractography (DTT). Methods: Twenty-one consecutive patients with DAI were recruited in this study. The DMN connectivity [medial prefrontal cortex (mPFC)—posterior cingulate cortex...
Objective This study investigated the macroscopic neural mechanisms of cognitive impairment after Deep Nuclei Intracerebral Hemorrhage (DNICH) from the dimensions of brain activity and brain networks, and further identified characteristic fingerprints of cognitive representation. Method Patients with cognitive impairment after DNICH and healthy controls (HC) were prospectively and consecutively...
Testosterone exerts widespread effects on brain structure and function, yet its influence on large-scale neural networks, particularly the default mode network (DMN), remains poorly understood. The role of the DMN in self-referential processing, social cognition, and mood regulation has been demonstrated over the last decade. Neuroimaging studies suggest a link between testosterone and...
Water-based contemplative and recovery practices — from head-out immersion and cold-water bathing to floatation-based sensory reduction — are consistently associated with shifts in autonomic and, increasingly, brainnetwork activity. This paper synthesizes the physiological literature on hydrostatic, thermal, vestibular, and sensory-attenuation effects of water immersion and evaluates the...
Background: Posterior α suppression, frontal θ enhancement and fronto-posterior α-band coupling are routinely interpreted together as an 'EEG-DMN-like' rest-to-task marker. Whether they replicate as a unitary pattern or dissociate across metric families, task windows and cognitive paradigms remains insufficiently characterised within a single harmonised pipeline. Methods: ds004148 (n = 60;...
Background Accelerated resting-state fMRI (rs-fMRI) may reduce scan time and participant burden, but whether shortened acquisitions preserve functional connectivity profiles and clinical associations remains unclear. This study compared hyperband and conventional acquisitions in characterizing default mode network (DMN) connectivity and associations with substance use. Methods A community...
Repetitive transcranial magnetic stimulation (rTMS) has been explored as an intervention in typical amnestic Alzheimer's Disease (AD). However, its effects on episodic and associative memory in atypical forms of AD are less known. Posterior cortical atrophy (PCA) is primarily characterized by visuospatial and visuoperceptual symptoms, although significant episodic memory deficits are often...
Objective Dysfunction of the default mode network (DMN) is strongly linked to pain processing, as well as onset and progression of chronic pain disorders; however, its specific role in the pathogenesis of tension-type headache (TTH) remains incompletely understood. This study aims to explore the network homogeneity (NH) of the DMN in the pathophysiological mechanisms underlying TTH. Methods...
ExploreAugust 23, 2026Siddhant Nikam, Nimisha S Narayan
Patients undergoing Still Point induction via compression of the fourth ventricle (CV4) in cranial osteopathy commonly report a distinctive quality of profound mental quiet, described as qualitatively different from ordinary relaxation. Cranial osteopathy, however, entered a prolonged crisis of scientific credibility once controlled work indicated that its founding construct, the Primary...