{
  "abstract": "Human brain function emerges from the interplay between recurrent local activity and distributed inter-regional interactions. However, a biologically interpretable framework for quantifying this balance between the two factors at the whole-brain level remains lacking. Here, we extended an established biophysical model to quantify inter-regional excitation and newly introduced the recurrent ratio (R-ratio), a measure of the relative balance between intra- and inter-regional excitation. Dynamical analyses showed that an optimal R-ratio supports a trade-off between network stability and flexibility. Applying this framework to healthy aging and Alzheimer's disease revealed progressively increased R-ratios with advancing age and disease severity. In healthy individuals, higher R-ratios were associated with age-related alterations in brain morphology, molecular pathology, and cognitive function, whereas Alzheimer's disease was characterized by increased R-ratios accompanied by reduced dynamical persistence. Together, these findings establish the R-ratio as a biologically interpretable marker of whole-brain excitation balance and demonstrate its utility for linking biophysical mechanisms with large-scale brain dynamics, aging, and neurodegeneration.",
  "abstract_shown": true,
  "affiliations": [
    "Korea University"
  ],
  "article_type": "New results",
  "arxiv": null,
  "author_total": 6,
  "authors": [
    {
      "affs": [
        0
      ],
      "name": "Y. Park"
    },
    {
      "name": "S. Kim"
    },
    {
      "affs": [
        0
      ],
      "name": "H. Park"
    },
    {
      "name": "T. D. Satterthwaite"
    },
    {
      "name": "B. Bernhardt"
    },
    {
      "affs": [
        0
      ],
      "name": "B.-y. Park"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/9z3vjxqksqp9x.bib",
  "cited_by": 0,
  "doi": "10.64898/2026.09.17.752536",
  "fulltext_url": "https://www.biorxiv.org/content/10.64898/2026.09.17.752536v1.full",
  "id": "9z3vjxqksqp9x",
  "issns": [],
  "landing_url": "https://www.biorxiv.org/content/10.64898/2026.09.17.752536v1",
  "language": null,
  "licence": "CC-BY",
  "licence_label": "CC BY",
  "licence_source": "article",
  "licence_url": "https://creativecommons.org/licenses/by/4.0/",
  "metadata_licence": null,
  "native_subjects": [
    [
      "biorxiv",
      "neuroscience"
    ],
    [
      "openalex",
      "2805|Neural dynamics and brain function"
    ]
  ],
  "openalex": "W7214240090",
  "pdf_url": "https://www.biorxiv.org/content/10.64898/2026.09.17.752536v1.full.pdf",
  "pmcid": null,
  "pmid": null,
  "published": "2026-09-17",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/9z3vjxqksqp9x.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:24:22Z",
      "native_id": "10.64898/2026.09.17.752536",
      "source": "biorxiv",
      "url": "https://www.biorxiv.org/content/10.64898/2026.09.17.752536v1"
    }
  ],
  "subjects": [
    {
      "field": "biology",
      "origin": "biorxiv:neuroscience",
      "subfield": "neuroscience"
    }
  ],
  "title": "The balance of local and distributed excitation shapes brain stability and reflects aging- and Alzheimer's disease-related alterations",
  "title_text": "The balance of local and distributed excitation shapes brain stability and reflects aging- and Alzheimer's disease-related alterations",
  "type": "preprint",
  "updated_at": "2026-10-30T12:24:22Z",
  "url": "https://research.draconitic.com/paper/9z3vjxqksqp9x",
  "venue": "bioRxiv",
  "versions": []
}