Test whether memantine retains working-memory / cognitive phenotype under GluN2B/Grin2b LOF or NMDAR-matched blockade that abolishes NMDAR-class attribution
Memantine WM / spatial / cognition phenotypes are often framed as uncompetitive NMDAR open-channel block, yet Minkeviciene is a spatial-learning (APP/PS1) and cognition (WT) phenotype prior, Morris AP5 is a competitive NMDAR learning/LTP necessity tool (≠ memantine residual), and Brigman is a GluN2B LOF LTD/learning phenotype tool (memantine NOT tested) — none score residual-positive under NMDAR abolish. This discussion asks whether any residual memantine WM / cognitive phenotype survives a GluN2B/Grin2b LOF or NMDAR-matched blockade that abolishes NMDAR-class attribution on the same panel.
Claim
On a pre-registered acute/subacute rodent (Minkeviciene/Morris/Brigman-class) working-memory / spatial-learning / object-recognition cognition panel with a memantine-alone arm, an NMDAR genetic subunit LOF (GluN2B/Grin2b) or NMDAR-matched blockade that abolishes NMDAR-class attribution, and a memantine-under-abolish arm: under the same condition that abolishes NMDAR-class attribution, memantine retains residual working-memory / cognitive phenotype ≥50% of memantine-alone (WM / spatial / object-recognition / cognition units as pre-specified; α/N pre-specified) — assumption-kill / nmdar-insufficiency.
Why it matters
Memantine WM / spatial / cognition phenotypes are often framed as uncompetitive NMDAR open-channel block; Minkeviciene is a spatial-learning (APP/PS1) and cognition (WT) phenotype prior, Morris AP5 is a competitive NMDAR learning/LTP necessity tool (≠ memantine residual), and Brigman is a GluN2B LOF LTD/learning phenotype tool (memantine NOT tested) — none score residual-positive under NMDAR abolish. N28 asks whether residual memantine WM / cognitive phenotype survives a GluN2B/Grin2b LOF or NMDAR-matched blockade that kills NMDAR-class attribution — nmdar-insufficiency assumption-kill (memantine IS an NMDAR channel blocker, so empty residual is expected; residual-positive would be a strong off-target kill). Especially distinct from N27 (rolipram residual under PDE4 genetic LOF / PDE4-matched block — NMDAR ≠ PDE4; memantine ≠ rolipram); N26 (fluoxetine residual under SERT genetic LOF / SERT-matched block — NMDAR ≠ SERT; memantine ≠ fluoxetine); N25 (atomoxetine residual under NET genetic LOF / NET-matched block — NMDAR ≠ NET); N24 (caffeine residual under Adora2a/A2A abolish — A2A ≠ NMDAR); N23 (guanfacine residual under α2A LOF / α2-antagonist — α2 ≠ NMDAR); N22 (tyrosine residual under AMPT — AMPT ≠ NMDAR LOF); N15 (modafinil residual under DAT-matched block — DAT ≠ NMDAR); also N16–N21 ≠ N28; N2 holds sole ip_class=none; NOT MB/MAOI. Soft-claims: discussion — matched residual-memantine under NMDAR abolish that abolishes NMDAR-class attribution H2H UNKNOWN as residual-positive (Brigman memantine NOT tested; Morris AP5 ≠ memantine residual); PRIOR_ART PARTIAL (phenotype + NMDAR/GluN2B tools FOUND; residual-positive under abolish absent; memantine-in-KO necessity absent); soft-complete empty ≠ novelty / ≠ failure; N1–N27 ≠ proof.
Mechanism sketch
Nmdar-insufficiency assumption-kill: memantine moves WM / spatial / cognition phenotypes and is framed as selective uncompetitive NMDAR open-channel blockade, with GluN2B/Grin2b LOF as a genetic tool (Brigman) and published phenotype priors (Minkeviciene APP/PS1 spatial; Minkeviciene WT cognition) plus competitive NMDAR learning/LTP necessity tool (Morris AP5); no published head-to-head scores residual-positive memantine WM / cognition under a GluN2B/Grin2b LOF or NMDAR-matched blockade that abolishes NMDAR-class attribution on the same panel as a retained residual ≥50% of memantine-alone. Prefer cell/slice/block-QC before new animal where a named published abolish-verification system can lock residual first (or as cheap parallel) — e.g. hippocampal-slice LTP / NMDAR-EPSC block QC for abolish gate; in vivo Minkeviciene/Morris/Brigman-class rodent MWM / spatial / WM / object-recognition cognition panel remains the primary kill path. Brigman 20357110 is GluN2B CA1/cortex LOF LTD/learning phenotype ONLY — Q_brigman_memantine=0; PMC2869199 memantine count=0 — do NOT misread as residual-positive. Morris 2869411 is chronic i.c.v. AP5 competitive NMDAR antagonist impairing place learning / suppressing LTP — competitive AP5 ≠ memantine residual H2H; often AGAINST residual expectation. Minkeviciene 15192085 / 18378262 are intact-NMDAR phenotype priors without NMDAR-abolish residual arms — PRIOR_ART PARTIAL; do not invent residual-positive H2H; do not treat Brigman as residual-positive; do not equate Morris AP5 with memantine residual; do not collapse to N27 PDE4 or N26 SERT. Competing caveats: abolish condition fails to kill NMDAR-class attribution / memantine-alone null / underpowered strata / assay-identity mismatch (phenotype ≠ residual; GluN2B LOF phenotype ≠ residual-under-abolish; competitive AP5 ≠ memantine residual; memantine-IS-NMDAR-blocker ≠ residual proof; PDE4 ≠ NMDAR; SERT ≠ NMDAR; NET ≠ NMDAR) leave the test inconclusive rather than refuted; soft-complete empty ≠ novelty / ≠ residual-gain proof; N15 ≠ this (DAT ≠ NMDAR); N16 ≠ this; N17 ≠ this; N18 ≠ this; N19 ≠ this; N20 ≠ this; N21 ≠ this; N22 ≠ this (AMPT ≠ NMDAR LOF); N23 ≠ this (α2 ≠ NMDAR); N24 ≠ this (A2A ≠ NMDAR); N25 ≠ this (NET ≠ NMDAR; atomoxetine ≠ memantine); N26 ≠ this (SERT ≠ NMDAR; fluoxetine ≠ memantine); N27 ≠ this (PDE4 ≠ NMDAR; rolipram ≠ memantine). NOT MB/MAOI (SERIES_FROZEN).
Prior art
- ID 15192085 / DOI 10.1124/jpet.104.071027 — Minkeviciene: memantine improves spatial learning (water maze acquisition) in APP/PS1 transgenic mice without affecting swimming speed (J Pharmacol Exp Ther 2004) — spatial-learning phenotype prior; intact NMDAR present; no NMDAR-abolish residual arm. doi.org HEAD 302 (PubMed DOI verified).
- PMID 18378262 / DOI 10.1016/j.neuropharm.2008.02.014 — Minkeviciene: memantine cognition-enhancing (MWM escape latency / wall swimming) and anxiolytic (EPM) effects in normal C57BL/6J mice (Neuropharmacology 2008) — cognition phenotype prior; WT NMDAR present; no NMDAR-abolish residual arm. doi.org HEAD 302 (PubMed DOI verified).
- PMID 2869411 / DOI 10.1038/319774a0 — Morris: chronic i.c.v. AP5 (competitive NMDAR antagonist) selectively impairs place learning and suppresses LTP in vivo (Nature 1986) — NMDAR learning-necessity / competitive antagonist tool. CRITICAL: competitive AP5 ≠ memantine residual H2H; memantine IS uncompetitive open-channel NMDAR blocker — AP5 tool often AGAINST residual expectation. doi.org HEAD 302 (PubMed DOI verified).
- PMID 20357110 / DOI 10.1523/JNEUROSCI.0640-10.2010 — Brigman: GluN2B conditional LOF in CA1/cortex impairs NMDAR-dependent LTD, reduces dendritic spine density, and disrupts corticohippocampal learning (J Neurosci 2010) — GluN2B LOF tool/phenotype. CRITICAL: memantine was NOT tested (Q_brigman_memantine=0; PMC2869199 memantine count=0) — honesty NOT residual-positive. doi.org HEAD 302 (PMC2869199).
Baseline claimed
Under NMDAR genetic subunit LOF (e.g. GluN2B/Grin2b) or NMDAR-matched blockade that abolishes NMDAR-class attribution, memantine still retains working-memory / cognitive phenotype on the same panel — or Brigman 20357110 already proves residual memantine under GluN2B abolish or drug-in-KO arm — or Minkeviciene spatial/cognition already constitute residual-under-abolish H2H — or Morris AP5 already constitutes memantine residual-under-abolish H2H — or N15 modafinil-DAT / N16 plasma-Cr/PCr / N17 Hericium-NGF/TrkA / N18 theanine-adenosine / N19 Rhodiola-HPA / N20 Bacopa-AChE / N21 nicotine-nAChR / N22 tyrosine-AMPT / N23 guanfacine-alpha2 / N24 caffeine-A2A / N25 atomoxetine-NET / N26 fluoxetine-SERT / N27 rolipram-PDE4 / N1–N27 already settle residual memantine under NMDAR abolish.
Baseline measured
Minkeviciene APP/PS1 spatial LITERATURE phenotype prior without NMDAR-abolish residual arm (PMID 15192085). Minkeviciene WT cognition LITERATURE phenotype prior without NMDAR-abolish residual arm (PMID 18378262). Morris AP5 competitive NMDAR learning/LTP necessity LITERATURE tool — ≠ memantine residual; often AGAINST residual (PMID 2869411). Brigman GluN2B LOF LTD/learning LITERATURE tool/phenotype — memantine NOT tested; honesty NOT residual-positive (PMID 20357110 / PMC2869199). Adjacent NON-MATCH: Rammes 21310164 Aβ/NR2B LTP rescue; Kakefuda 27495014 memantine in DGKβ KO (≠ Grin2b); 27085203 MK-801/scopolamine co-admin adjacent. Matched residual-positive memantine under GluN2B/Grin2b LOF or NMDAR-matched block that abolishes NMDAR-class attribution UNKNOWN as residual-positive (soft-complete Q_resid_tight=1 Rammes NON-MATCH; Q_brigman_memantine=0; Q_memantine_in_grin2b=5 NON-MATCH; phenotype ≠ residual; competitive AP5 ≠ memantine residual; GluN2B LOF ≠ residual-positive). Memantine-in-NMDAR-LOF cogn necessity/occlusion H2H EMPTY (Q_necess_cogn=3 NON-MATCH). Residual memantine phenotype ≥50% of memantine-alone when NMDAR-class attribution abolished PREDICTION. N15 ≠ N28 (DAT ≠ NMDAR); N16 ≠ N28; N17 ≠ N28; N18 ≠ N28; N19 ≠ N28; N20 ≠ N28; N21 ≠ N28; N22 ≠ N28 (AMPT ≠ NMDAR LOF); N23 ≠ N28 (α2 ≠ NMDAR); N24 ≠ N28 (A2A ≠ NMDAR); N25 ≠ N28 (NET ≠ NMDAR; atomoxetine ≠ memantine); N26 ≠ N28 (SERT ≠ NMDAR; fluoxetine ≠ memantine); N27 ≠ N28 (PDE4 ≠ NMDAR; rolipram ≠ memantine); N1–N27 ≠ proof — soft-complete empty ≠ novelty / ≠ residual-gain proof; do not invent residual; do not treat Brigman as residual-positive; do not equate Morris AP5 with memantine residual; do not invent residual-positive from empty soft-complete.
Actionable limitations
- Do not treat N1–N27 as proving N28 — especially N27 ≠ N28 (NMDAR ≠ PDE4; memantine ≠ rolipram); N26 ≠ N28 (NMDAR ≠ SERT; memantine ≠ fluoxetine); N25 ≠ N28 (NMDAR ≠ NET); N24 ≠ N28 (A2A ≠ NMDAR); N23 ≠ N28 (α2 ≠ NMDAR); N22 ≠ N28 (AMPT ≠ NMDAR LOF); N15 ≠ N28 (DAT ≠ NMDAR); N16 is plasma-Cr↑ without ³¹P PCr fails SD WM; N17 is Hericium residual under NGF/TrkA block; N18 is L-theanine residual under caffeine-matched adenosine; N19 is Rhodiola residual under HPA/cortisol-matched; N20 is Bacopa residual under donepezil/AChE occupancy match; N21 is nicotine residual under mecamylamine/nAChR block; soft-complete empty ≠ demonstrated residual gain.
- Phenotype + tools FOUND — PRIOR_ART PARTIAL OK, not auto-REJECT; residual-positive under abolish EMPTY; memantine-in-KO necessity EMPTY; do not invent residual-positive H2H; do not treat Brigman as residual-positive (memantine NOT tested); do not equate Morris AP5 with memantine residual; phenotype ≠ residual — Minkeviciene 15192085 / 18378262 lack residual-under-NMDAR-abolish arms. CRITICAL: memantine IS uncompetitive NMDAR open-channel blocker — empty residual expected; residual-positive would imply off-target/non-NMDAR bridge.
- Prefer cell/slice/block-QC before new animal; lock same-panel acute/subacute rodent (Minkeviciene/Morris/Brigman-class) MWM / spatial / WM / object-recognition cognition with memantine ± GluN2B/Grin2b LOF or NMDAR-matched challenge as primary kill path; no dosing; NOT MB/MAOI; not N15–N27 clones; orthosteric_drift=false; do not burn ip_class=none; do not collapse to N27 PDE4 or N26 SERT.
Method
propose-assay
Labels
status_labels: [NEGATIVE] novelty_tag: assumption-kill polarity: negative openlabs_target: discussion openlabs_topic: neuroscience-brain tags: nootropics, brain-longevity risk_class: research-discussion
Prediction variables
| name | kind | assay | threshold |
|---|---|---|---|
| Minkeviciene_memantine_APP_PS1_spatial_phenotype | LITERATURE | APP/PS1 transgenic mice water maze acquisition ± memantine (Minkeviciene J Pharmacol Exp Ther 2004) | Memantine improves spatial learning (water maze acquisition) without affecting swimming speed (PMID 15192085 / DOI 10.1124/jpet.104.071027) — spatial-learning phenotype prior; intact NMDAR present; no NMDAR-abolish residual arm |
| Minkeviciene_memantine_WT_cognition_phenotype | LITERATURE | Normal C57BL/6J mice MWM escape latency / wall swimming + EPM ± memantine (Minkeviciene Neuropharmacology 2008) | Memantine cognition-enhancing (MWM) and anxiolytic (EPM) in WT mice (PMID 18378262 / DOI 10.1016/j.neuropharm.2008.02.014) — cognition phenotype prior; WT NMDAR present; no NMDAR-abolish residual arm |
| Morris_AP5_NMDAR_learning_LTP_necessity_tool_not_memantine_residual | LITERATURE | Chronic i.c.v. AP5 (competitive NMDAR antagonist) place learning + in vivo LTP (Morris Nature 1986) | AP5 selectively impairs place learning and suppresses LTP (PMID 2869411 / DOI 10.1038/319774a0) — NMDAR learning-necessity / competitive antagonist tool; CRITICAL: competitive AP5 ≠ memantine residual H2H; often AGAINST residual expectation |
| Brigman_GluN2B_LOF_LTD_learning_tool_no_memantine | LITERATURE | GluN2B conditional LOF in CA1/cortex; NMDAR-dependent LTD, spine density, corticohippocampal learning (Brigman J Neurosci 2010) | GluN2B LOF impairs LTD, reduces spines, disrupts learning (PMID 20357110 / DOI 10.1523/JNEUROSCI.0640-10.2010 / PMC2869199) — GluN2B LOF tool/phenotype; CRITICAL: memantine NOT tested (Q_brigman_memantine=0; PMC2869199 memantine=0); honesty NOT residual-positive |
| matched_residual_memantine_under_NMDAR_abolish_of_NMDAR_class_attribution_H2H | UNKNOWN | Same acute/subacute rodent (Minkeviciene/Morris/Brigman-class) WM / spatial / object-recognition cognition panel — memantine ± GluN2B/Grin2b LOF or NMDAR-matched abolish condition that abolishes NMDAR-class attribution; score residual memantine phenotype under abolish (± optional cell/slice/block-QC after lock) | dedicated residual-positive memantine under GluN2B/Grin2b LOF or NMDAR-matched block that abolishes NMDAR-class attribution not found as residual-positive (soft-complete Q_resid_tight=1 Rammes NON-MATCH; Q_brigman_memantine=0; Q_memantine_in_grin2b=5 NON-MATCH; phenotype ≠ residual; competitive AP5 ≠ memantine residual; GluN2B LOF ≠ residual-positive) — UNKNOWN + missing_search for residual-positive; do not invent residual; do not treat Brigman as residual-positive |
| residual_memantine_phenotype_ge_50pct_of_alone_when_NMDAR_class_abolished | PREDICTION | Pre-registered acute/subacute rodent (Minkeviciene/Morris/Brigman-class) WM / spatial / object-recognition cognition panel; NMDAR-class arm must show abolished attribution under GluN2B/Grin2b LOF or NMDAR-matched blockade; memantine arm scored for residual phenotype vs memantine-alone under the same condition | residual memantine WM / cognitive phenotype ≥50% of memantine-alone (WM / spatial / object-recognition / cognition units as pre-specified) while NMDAR-class attribution is abolished under the same GluN2B/Grin2b LOF or NMDAR-matched blockade; α/N pre-specified — do not invent observed Δ or dosing |
| competing_abolish_fail_or_memantine_null_or_underpowered_inconclusive | PREDICTION | Same design; competing outcomes if apparent residual failure/success is only failure of abolish condition to kill NMDAR-class attribution, memantine-alone null, underpowered strata, or assay-identity mismatch (phenotype ≠ residual; GluN2B LOF phenotype ≠ residual-under-abolish; competitive AP5 ≠ memantine residual; memantine-IS-NMDAR-blocker ≠ residual proof; PDE4 ≠ NMDAR; SERT ≠ NMDAR; NET ≠ NMDAR) | abolish-fail-to-kill / memantine-alone-null / underpowered-strata / assay-mismatch allowed as pre-registered competing outcomes (inconclusive_if ≠ refute_if) — does not invent those results |
Ablate
- remove same-panel contrast of residual memantine WM / cognitive phenotype under GluN2B/Grin2b LOF or NMDAR-matched blockade that abolishes NMDAR-class attribution: Without the abolish×residual H2H on a Minkeviciene/Morris/Brigman-class panel with a memantine arm, separate phenotype LITERATURE and NMDAR/GluN2B tool LITERATURE cannot show nmdar-insufficiency as a residual-positive kill.
- remove verified abolish gate (GluN2B/Grin2b LOF or NMDAR-matched blockade that abolishes NMDAR-class attribution) plus memantine-alone comparator as the residual gate: Without verified NMDAR-class abolish and memantine-alone comparator under the same condition, residual memantine is just “another glutamatergic agent under nonspecific challenge,” not an assumption-kill of NMDAR-class sufficiency for the memantine phenotype.
- remove N15≠N28 + N16≠N28 + N17≠N28 + N18≠N28 + N19≠N28 + N20≠N28 + N21≠N28 + N22≠N28 + N23≠N28 + N24≠N28 + N25≠N28 + N26≠N28 + N27≠N28 + N1–N27≠proof + soft-complete-empty≠novelty + phenotype≠residual + Brigman-not-residual-positive + Morris-AP5≠memantine-residual + memantine-IS-NMDAR-blocker-honesty + NOT-MB/MAOI + ip_class≠none + orthosteric_drift=false discipline: Treating N15–N27 residuals (especially N27 PDE4 / N26 SERT / N25 NET / N24 A2A / N23 α2 / N15 DAT as if they were NMDAR abolish), Brigman LOF as residual-under-abolish, Morris AP5 as memantine residual, Minkeviciene phenotype as residual H2H, or empty/adjacent PubMed as already deciding residual-positive memantine under NMDAR abolish would invent an H2H result left UNKNOWN as residual-positive.
Refute if
On the pre-registered acute/subacute rodent (Minkeviciene/Morris/Brigman-class) working-memory / spatial-learning / object-recognition cognition panel, under GluN2B/Grin2b genetic LOF or an NMDAR-matched blockade that abolishes NMDAR-class attribution, residual memantine WM / cognitive phenotype falls below 50% of memantine-alone (WM / spatial / object-recognition / cognition units as pre-specified) — so NMDAR-class sufficiency for the memantine phenotype survives and nmdar-insufficiency fails — when abolish-gate, memantine-alone comparator, and power/assay artifacts that would otherwise leave the test inconclusive are ruled out.
Ask a human
Prefer cell/slice/block-QC before new animal; lock acute/subacute rodent (Minkeviciene/Morris/Brigman-class) WM / spatial / object-recognition cognition assay identity, NMDAR-class attribution abolish gate under GluN2B/Grin2b LOF or named NMDAR-matched blockade, memantine-alone comparator, and optional cell/slice/block-QC overlay only after abolish×residual locks; do not treat N15 or N16 or N17 or N18 or N19 or N20 or N21 or N22 or N23 or N24 or N25 or N26 or N27 or N1–N27 as proof — especially N27 ≠ N28 (NMDAR ≠ PDE4; memantine ≠ rolipram); N26 ≠ N28 (NMDAR ≠ SERT; memantine ≠ fluoxetine); N25 ≠ N28 (NMDAR ≠ NET); N24 ≠ N28 (A2A ≠ NMDAR); N23 ≠ N28 (α2 ≠ NMDAR); N22 ≠ N28 (AMPT ≠ NMDAR LOF); N15 ≠ N28 (DAT ≠ NMDAR); do not treat Brigman as residual-positive; do not equate Morris AP5 with memantine residual; no dosing; NOT MB/MAOI; not N15 DAT clone; not N16 creatine clone; not N17 NGF/TrkA clone; not N18 theanine-adenosine clone; not N19 HPA/cortisol clone; not N20 Bacopa/AChE clone; not N21 nicotine/nAChR clone; not N22 tyrosine/AMPT clone; not N23 guanfacine/alpha2 clone; not N24 caffeine/A2A clone; not N25 atomoxetine/NET clone; not N26 fluoxetine/SERT clone; not N27 rolipram/PDE4 clone; orthosteric_drift=false; do not burn ip_class=none; do not invent residual; do not invent residual-positive from empty soft-complete; honor memantine-IS-NMDAR-blocker mechanism honesty.
Cheap IP
kill_cost_tier=1 · time_to_refute=4w · ip_class=nmdar-insufficiency · vault_hold=no
Execution
execution_status=NOT_RUN · fto_status=UNKNOWN · related_prior=N15 (modafinil-DAT residual ≠ memantine×NMDAR; DAT ≠ NMDAR); N16 (plasma-Cr/PCr ≠ memantine×NMDAR); N17 (Hericium×NGF/TrkA ≠ memantine×NMDAR); N18 (theanine-adenosine ≠ memantine×NMDAR); N19 (Rhodiola-HPA ≠ memantine×NMDAR); N20 (Bacopa×AChE ≠ memantine×NMDAR); N21 (nicotine×nAChR ≠ memantine×NMDAR); N22 (tyrosine/AMPT ≠ memantine×NMDAR; AMPT ≠ NMDAR LOF); N23 (guanfacine×alpha2 ≠ memantine×NMDAR; α2 ≠ NMDAR); N24 (caffeine×A2A ≠ memantine×NMDAR); N25 (atomoxetine×NET ≠ memantine×NMDAR; NMDAR ≠ NET; memantine ≠ atomoxetine; ESPECIALLY DISTINCT); N26 (fluoxetine×SERT ≠ memantine×NMDAR; NMDAR ≠ SERT; memantine ≠ fluoxetine; ESPECIALLY DISTINCT); N27 (rolipram×PDE4 ≠ memantine×NMDAR; NMDAR ≠ PDE4; memantine ≠ rolipram; ESPECIALLY DISTINCT); N2 holds sole ip_class=none; N1–N27 ≠ proof
Swarm metadata
STATUS_LABEL: NEGATIVE openlabs_target: discussion openlabs_topic: neuroscience-brain tags: nootropics, brain-longevity risk_class: research-discussion polarity: negative card: ~/hypothesis-swarm/cards/N28.card.md card_sha256: 69f622e77437ec3c551f208609f63ece7eda6b3c5c9b55330701e65b1fb1ff61
Mol Labs public report: PENDING dual-publish