Four documented cases of circuit theory preceding its anatomy cannot be distinguished from survivorship bias, because no survey counts the denominator of all proposed circuit theories

The vault now holds four independently-sourced cases of a systems-neuroscience circuit theory proposed as pure computation and confirmed by anatomy or connectomics only after a multi-decade wait: sound localization (Jeffress 1948 → Carr & Konishi 1990, ~42y, claim-jeffress-1948-place-theory-waited-decades-for-anatomical-confirmation); head-direction coding (Zhang 1996 → Turner-Evans et al. 2020, ~24y, claim-drosophila-connectome-confirmed-zhang-1996-ring-attractor); retinal direction selectivity (Barlow & Levick 1965 → Briggman et al. 2011, ~46y, claim-barlow-levick-1965-direction-selectivity-confirmed-briggman-2011); and cerebellar motor learning (Marr/Ito 1969–70 → Ito & Kano 1982, ~12y, claim-marr-ito-cerebellar-ltd-1969-confirmed-ito-kano-1982). Four cases across independent brain systems and research lineages make "two cherry-picked cases" a harder objection to sustain than it was for the original two-instance synthesis, claim-neural-circuit-theories-wait-decades-for-anatomical-confirmation.

But no source located in this search performs the survey that would settle the strong claim: a count of all circuit theories proposed in systems neuroscience, tracking which were later confirmed, which disconfirmed, which revised, and which remain untested. Without that denominator, four documented successes cannot distinguish two very different explanations: (a) circuit theories genuinely tend to run ahead of the instruments that could test them, or (b) theories that later get vindicated are simply the ones retold in reviews and textbooks, while disconfirmed or complicated theories quietly drop out of the story. The vindicated cases are precisely the ones that acquire anniversary retrospectives (the Marr/Ito/Albus "fifty years since" review; a full Nature Reviews treatment of Barlow-Levick) — which is the exact mechanism by which survivorship bias would produce an apparent pattern with no underlying regularity.

This is a specific instance of the epistemics in claim-mcgrew-humans-systematically-over-trust-arguments-from-silence and the moc-argument-from-silence cluster: a search that returns only successes is not evidence that failures are rare. One suggestive counter-pointer — the "canonical cortical microcircuit," where connectomic study reportedly found cortical wiring more heterogeneous than the canonical model implied — was flagged as a lead but not developed here. The core question remains routed at question-do-neural-circuit-theories-systematically-precede-their-anatomy.