{
  "abstract": "Parkinson's disease is asymmetric, but representations that collapse left--right measurements discard that direction. We separated overall dopamine-transporter availability from hemispheric distribution: mean putamen specific-binding ratio (SBR) indexed overall DaT signal, whereas signed asymmetry retained which hemisphere was relatively more affected. Signed asymmetry aligned with contralateral MDS-UPDRS Part III laterality in PPMI (n=1,367; r=0.676) and S4 (n=56; r=0.551). In 1,204 PPMI landmarks, each 0.1 asymmetry corresponded to a 0.0507 increase in 12-month laterality (95\\% CI 0.0387--0.0626); held-out \\(R^2\\) improved 0.0176 over non-directional imaging but was uncertain under a bounded link. Exploratory imaging--clinical disagreement marked lower side persistence (OR=0.491 per IQR-standardized unit; 0.297--0.711). Signed direction therefore distinguishes mirror-image and conflicting dopaminergic--motor states erased by mean-only summaries. This is a reproducible biological coordinate, not global progression, treatment benefit or clinical utility.",
  "abstract_shown": true,
  "affiliations": [
    "U Texas"
  ],
  "article_type": "New results",
  "arxiv": null,
  "author_total": 3,
  "authors": [
    {
      "name": "H. Tirhekar"
    },
    {
      "name": "P. Yadav"
    },
    {
      "affs": [
        0
      ],
      "name": "C. Bajaj"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/0rqg2ghkembtj.bib",
  "cited_by": 0,
  "doi": "10.64898/2026.09.23.753983",
  "fulltext_url": "https://www.biorxiv.org/content/10.64898/2026.09.23.753983v1.full",
  "id": "0rqg2ghkembtj",
  "issns": [],
  "landing_url": "https://www.biorxiv.org/content/10.64898/2026.09.23.753983v1",
  "language": null,
  "licence": "CC-BY-NC-ND",
  "licence_label": "CC BY-NC-ND",
  "licence_source": "article",
  "licence_url": "https://creativecommons.org/licenses/by-nc-nd/4.0/",
  "metadata_licence": null,
  "native_subjects": [
    [
      "biorxiv",
      "neuroscience"
    ],
    [
      "openalex",
      "2728|Parkinson's Disease Mechanisms and Treatments"
    ]
  ],
  "openalex": "W7214714264",
  "pdf_url": "https://www.biorxiv.org/content/10.64898/2026.09.23.753983v1.full.pdf",
  "pmcid": null,
  "pmid": null,
  "published": "2026-09-23",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/0rqg2ghkembtj.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:25:15Z",
      "native_id": "10.64898/2026.09.23.753983",
      "source": "biorxiv",
      "url": "https://www.biorxiv.org/content/10.64898/2026.09.23.753983v1"
    }
  ],
  "subjects": [
    {
      "field": "biology",
      "origin": "biorxiv:neuroscience",
      "subfield": "neuroscience"
    }
  ],
  "title": "Signed Dopaminergic Asymmetry Tracks Contralateral Motor Laterality in Parkinsons Disease",
  "title_text": "Signed Dopaminergic Asymmetry Tracks Contralateral Motor Laterality in Parkinsons Disease",
  "type": "preprint",
  "updated_at": "2026-10-30T12:25:15Z",
  "url": "https://research.draconitic.com/paper/0rqg2ghkembtj",
  "venue": "bioRxiv",
  "versions": []
}