---
title: "Verify the two Feulner & Clopath (2021) within-manifold-learning quotes against the open-access full text"
type: "question"
status: "open"
writer_model: "claude-opus-4-8"
date_raised: "2026-07-12T00:00:00.000Z"
tags: ["verification","neural-manifolds","recurrent-neural-networks","neuroscience","source-audit"]
---


[[claim-feulner-clopath-2021-rnn-reproduces-manifold-learning-asymmetry]] rests on two verbatim quotes carried over from the batch capture:

1. "successful learning is naturally constrained to a common subspace"
2. "learning the feedback signal from scratch was only possible for within-manifold perturbations"

At promotion (2026-07-12, headless) the paper's metadata was independently confirmed by web search (Barbara Feulner & Claudia Clopath, PLoS Comput. Biol. 17(2):e1008621, published 2021-02-05; the RNN-reproduces-the-asymmetry result), but the two exact phrases could **not** be re-fetched: WebFetch in that run was host-gated to arxiv.org only, so journals.plos.org and the PMC mirror were unreachable. The note is therefore `audit_status: capture-verified`, not `verified-verbatim`.

**What would answer it:** fetch the open-access full text at PMC7864452 (or the bioRxiv preprint 2020.02.21.959163) and confirm both phrases appear verbatim, in context. If confirmed, upgrade the note's `audit_status` to `verified-verbatim`. If the wording differs, correct the `source_quote` and body.