{
  "abstract": "Neural dedifferentiation, characterized by reduced distinctiveness of neural representations, is a robust feature of cognitive aging. Multivoxel pattern analyses often operationalize neural distinctiveness as the difference between within-category similarity (reliability) and between-category similarity (confusability). However, it remains unclear whether age-related reductions in distinctiveness are driven by decreases in reliability, increases in confusability, or both, and whether these components demonstrate similar longitudinal trajectories. Using cross-sectional and longitudinal data from the Michigan Neural Distinctiveness (MiND) study, we decomposed distinctiveness into its two components across visual, auditory, and motor cortex in more than 200 young (18-29 years) and older adults (65-94 years) and estimated cross-sectional between-person age differences and longitudinal within-person change simultaneously in mixed-effects models. We found that reliability was lower in older vs. younger adults cross-sectionally, and this reduction was significantly larger than the corresponding effect on confusability. Moreover, reliability also declined longitudinally within individuals across a mean interval of four years. These findings indicate that age-related dedifferentiation is driven primarily by declining reliability rather than increasing confusability, and that reporting distinctiveness alone can conceal substantial age-related change in its components. Keywords: Dedifferentiation, distinctiveness, reliability, confusability, aging, longitudinal study",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": null,
  "author_total": 5,
  "authors": [
    {
      "name": "Tiantian Yang"
    },
    {
      "name": "Molly Simmonite"
    },
    {
      "name": "Ethan Maddox"
    },
    {
      "name": "Bingjie Liu"
    },
    {
      "name": "Thad Polk"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/7xf74pnb00r4p.bib",
  "cited_by": 0,
  "doi": "10.31234/osf.io/jb5zn_v1",
  "fulltext_url": null,
  "id": "7xf74pnb00r4p",
  "issns": [],
  "landing_url": "https://osf.io/preprints/psyarxiv/jb5zn_v1/",
  "language": null,
  "licence": "CC-BY-4.0",
  "licence_label": "CC BY 4.0",
  "licence_source": "article",
  "licence_url": "https://creativecommons.org/licenses/by/4.0/",
  "metadata_licence": null,
  "native_subjects": [
    [
      "bepress",
      "Cognitive Neuroscience"
    ],
    [
      "bepress",
      "Neuroscience"
    ],
    [
      "openalex",
      "2805|Functional Brain Connectivity Studies"
    ]
  ],
  "openalex": "W7223446058",
  "pdf_url": "https://osf.io/jb5zn/download",
  "pmcid": null,
  "pmid": null,
  "published": "2026-10-24",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/7xf74pnb00r4p.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:19:20Z",
      "native_id": "jb5zn",
      "source": "osf",
      "url": "https://osf.io/preprints/psyarxiv/jb5zn_v1/"
    }
  ],
  "subjects": [
    {
      "field": "biology",
      "origin": "bepress:Cognitive Neuroscience",
      "subfield": "neuroscience"
    }
  ],
  "title": "Age-Related Neural Dedifferentiation Is Driven by Declining Reliability",
  "title_text": "Age-Related Neural Dedifferentiation Is Driven by Declining Reliability",
  "type": "preprint",
  "updated_at": "2026-10-30T12:19:20Z",
  "url": "https://research.draconitic.com/paper/7xf74pnb00r4p",
  "venue": "PsyArXiv",
  "versions": []
}