{
  "id": 3955257,
  "title": "Noradrenergic infraslow rhythm during sleep is the critical link between heart-rate dynamics and memory consolidation",
  "url": "https://urgent.news/2026/08/28/noradrenergic-infraslow-rhythm-during-sleep-is-the-critical-link",
  "topic": "health",
  "section": "Health & Medicine",
  "published": "2026-08-28T00:00:00.000Z",
  "source": {
    "name": "eLife",
    "slug": "elife",
    "url": "https://elifesciences.org/articles/110252"
  },
  "original_language": "en",
  "account": "Recent studies reveal the brain's arousal system continues active during slumber, with a rhythmic locus coeruleus (LC) activity influencing sleep structure and aiding memory formation. The LC discharges norepinephrine (NE) in infraslow (~0.02 Hz) pulses that regulate NREM sleep spindles. Our research reveals that heart rate (HR) variations during NREM sleep align tightly with these NE patterns, designating the LC as a primary promoter of very-low-frequency HR variability (VLF-HRV), a lesser-known autonomic signal. Employing optogenetics, we observed that brief LC suppression dampens HR deceleration, while LC stimulation triggers rapid HR acceleration, indicating a direct LC-HR relationship during slumber that persists within a specific LC activity spectrum but falters when LC activity surges. We also discovered that infraslow HR variability serves as a cross-species indicator of spindle-driven memory processing. In mice, the magnitude of HR decelerations during NREM correlates with spindle frequency and subsequent memory performance. Strikingly, human sleepers exhibit the same pattern: larger VLF-HR fluctuations during NREM coincide with heightened spindle generation and superior overnight memory retention. These findings elucidate a mechanism whereby regulated fluctuations in LC activity, up to a critical threshold, modulate autonomic physiology during sleep and establish infraslow HR variability as a non-invasive gauge of brainstem function and memory-enhancing slumber. Given that LC degeneration initiates early in neurodegenerative diseases, sleep-derived HR parameters may function as a scalable signal of incipient neuromodulatory impairment.",
  "summary": "Recent work shows that the brain’s arousal system remains active during sleep, with rhythmic locus coeruleus (LC) activity shaping sleep architecture and supporting memory consolidation. The LC releases norepinephrine (NE) in infraslow (~0.02 Hz) bouts that gate NREM sleep spindles. Here, we demonstrate that heart rate (HR) fluctuations during NREM are tightly phase-locked to these NE rhythms,…",
  "key_points": [],
  "editors_take": null,
  "illustration": null,
  "coverage": {
    "outlets": 1,
    "also_reported_by": []
  },
  "ai_generated": true,
  "disclaimer": "Summaries, key points and the editor’s take are written by software from other outlets’ reporting and may contain errors — always check the linked original."
}