C29 Preschool brain training
narrowed 1 attack: 1 narrowed · serves Q1 · last change 5 November 2026
Training preschool children's executive functions (ages 3–6) raises their scores on executive-function tests by about a third of a standard deviation, but has not been shown to raise learning-related or academic outcomes reliably compared with control groups: one meta-analysis found no significant extra effect on learning and behaviour outcomes pooled together (g = 0.17, not significant; Scionti et al. 2020), while another found literacy and numeracy gains of about 0.4 standard deviations in 4- to 6-year-olds right after training, resting on very few studies per outcome and including non-randomised ones (Birtwistle et al. 2025).
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Where it holds
All limits (7)
Inside the circle: the core of the claim. Outside: every bound and carve-out in the claim file, numbered, with the attack that forced or added it where the record shows one.
forced by a narrowing attackin the original wordingwritten at creation, or added without a narrowing
Warm cards in the list were added by later attacks; plain cards were in the original draft or written at creation.
Stand-alone cognitive training for ages 3–6 (computer or game-based tasks); not whole curricula such as Tools of the Mind and not physical activity.
Written when the claim was created (29 October 2026); not forced by an attack
Evidence on file: Scionti, Cavallero, Zogmaister & Marzocchi 2020 (Frontiers in Psychology 10, 2812, DOI 10.3389/fpsyg.2019.02812; full text read 2026-11-05, open access, PMC6965160): 32 studies (randomised or pre-post with an active or passive control, at least 10 sessions), 123 effect sizes; executive functions g = 0.352; larger for at-risk children.
Written when the claim was created (29 October 2026); not forced by an attack
Wording changed later: Added with attack #3 (corrected; it did not narrow the claim) · Scionti, Cavallero, Zogmaister & Marzocchi 2020 · 5 November 2026.
Non-EF outcomes (learning-related, behaviour and problem-behaviour measures pooled together): 39 outcomes from 15 studies, g = 0.169 (SE 0.106, 95% CI −0.047 to 0.383, p = .122); the discussion gives g = 0.10 for the same analysis, an inconsistency in the paper; academic outcomes were not pooled on their own.
Added with attack #3 (corrected; it did not narrow the claim) · Scionti, Cavallero, Zogmaister & Marzocchi 2020 · 5 November 2026
Melby-Lervåg & Hulme 2013 (Developmental Psychology; already in the library): working-memory training gave near but not far transfer (adjacent support).
Written when the claim was created (29 October 2026); not forced by an attack
Weakened 2026-10-31 (nightly attacks): Birtwistle, Chernikova, Wünsch & Niklas 2025 (SAGE Open 15(1), DOI 10.1177/21582440241311060; full text, open access): 57 published RCTs and quasi-experiments of EF training (at least 80 minutes) in typically developing children aged 3–14, immediate post-tests only; ages 4–6 (29 studies): near transfer g = 0.25, far transfer g = 0.34 (p = .05), literacy g = 0.40 (df = 4), numeracy g = 0.39 (df = 5), reasoning ns; I² = 84%.
Forced by attack #1 · Birtwistle, Chernikova, Wünsch & Niklas 2025 · 31 October 2026
Melby-Lervåg & Hulme 2013 (full text, corrected 2026-10-31): working-memory training at all ages, mean 12 hours; immediate word decoding d = 0.13 (95% CI −0.07 to 0.35) and arithmetic d = 0.07 (−0.13 to 0.27), both non-significant; follow-ups 3–8 months later all non-significant (Table 4).
Added with attack #2 (corrected; it did not narrow the claim) · Melby-Lervåg & Hulme 2013 · 31 October 2026
The 'no academic gain' side rests on Scionti et al.'s pooled non-EF estimate, which mixes learning-related and behaviour outcomes (full text read 2026-11-05).
Forced by attack #1 · Birtwistle, Chernikova, Wünsch & Niklas 2025 · 31 October 2026
Wording changed later: Added with attack #3 (corrected; it did not narrow the claim) · Scionti, Cavallero, Zogmaister & Marzocchi 2020 · 5 November 2026.
2 of 7 bounds and carve-outs were forced by a specific attack.
How it changed
The ledger records 1 attack (and 2 corrections to our notes), but no earlier wording of C29 is on record, so the text cannot be replayed step by step. Only the current wording is shown.
Training preschool children's executive functions (ages 3–6) raises their scores on executive-function tests by about a third of a standard deviation, but has not been shown to raise learning-related or academic outcomes reliably compared with control groups: one meta-analysis found no significant extra effect on learning and behaviour outcomes pooled together (g = 0.17, not significant; Scionti et al. 2020), while another found literacy and numeracy gains of about 0.4 standard deviations in 4- to 6-year-olds right after training, resting on very few studies per outcome and including non-randomised ones (Birtwistle et al. 2025).
What would change this
What would kill it: A meta-analysis of randomised preschool cognitive-training trials finds a reliable gain on academic or learning-related outcomes, not only on executive-function tests, on a delayed test or with enough studies per outcome that the gain does not rest on a handful (sharpened 2026-10-31 with the weaken: Birtwistle et al. 2025 mixes randomised and quasi-experimental studies and reports immediate tests only). Added as a claim on 29 October 2026, promoted from a candidate belief in the evidence library.
Attack record
1 attack: 1 narrowed. Counts of attacks, not a score.
Full attack list (1)
A 2025 meta-analysis of 57 executive-function training studies in typically developing children found that 4- to 6-year-olds improved on literacy (g = 0.40) and numeracy (g = 0.39) tests right after training, not only on executive-function tests, so C29's flat statement that such training "does not raise learning-related or academic outcomes" is not established.
Strongest reading and verdict reasoning
Steelmans to: C29's academic prong rests on one meta-analysis read only in its abstract (Scionti et al. 2020: "no significant extra effect"); a newer, larger meta-analysis covering the same age band and the same kind of stand-alone cognitive training reports positive academic estimates of about 0.4 SD for ages 4–6, near-and-far transfer not significantly different, and no sign of publication bias, so the most the evidence supports is that academic gains are unproven, not that they are absent.
Why: Nightly-attacks 2026-10-31 Europe/Stockholm. Full text: 57 published RCTs or quasi-experiments with a treated or untreated control and pre/post tests; typically developing children aged 3–14; at least 80 minutes of training; immediate post-tests only. Overall g = .23 (95% CI .09 to .37). Ages 4–6 (29 studies): near transfer g = 0.25 (p = .004), far transfer g = 0.34 (SE .15, p = .05, df = 11), literacy g = 0.40 (SE .09, p = .01, df = 4), numeracy g = 0.39 (SE .08, p = .003, df = 5), reasoning 0.33 (ns); I² = 84%; funnel, asymmetry test and p-curve showed no publication bias; type of control not a significant predictor. Kill withheld: C29's kill line asks for randomised trials, and this pool mixes in quasi-experiments; tests were immediate only; the age-band literacy and numeracy estimates rest on 4 and 5 degrees of freedom; far transfer for ages 4–6 was only marginal (p = .05). So the claim narrows from "does not raise" to "has not been shown to raise reliably". Not a duplicate (empty ledger before tonight); not a restatement (Bounds named no positive academic estimate). Not a preprint. Status alive → weakened. Claim field, Bounds and kill line rewritten in the same turn; brief and diagram core rewritten (C29 has no front-page rule).
Corrections to our notes
These fix a number or a fact in our notes. They are not attacks and do not count toward the floor of 3 survivals.
- — Checked against the full text of the study: facts behind the "adjacent support" line.
Details
What was checked: facts behind the "adjacent support" line; no kill-condition test.
Why: Full text: working-memory training at all ages, mean training 12 hours; immediate word decoding d = 0.13 (95% CI −0.07 to 0.35) and arithmetic d = 0.07 (−0.13 to 0.27), both non-significant (forest-plot sections for decoding and arithmetic); pretest-to-follow-up differences 3–8 months later all non-significant (Table 4: decoding 0.13, arithmetic 0.18). The CI sentence that mining flagged as looking swapped (p. 10) was not quoted. Claim text, Status and kill line unchanged by this entry. Not a survival; does not count toward the floor.
- — Limits and claim-text fact fix from the full text of Scionti et al. 2020, which C29 cited as "read only in its abstract".
Details
What was checked: facts behind the "no significant extra effect" clause; no kill-condition test.
Why: Nightly-attacks 2026-11-05 Europe/Stockholm. Full text, Results ("Effect of EF Training on Additional Non-EF Outcomes"): 39 outcomes from 15 studies, learning-related, behaviour and problem-behaviour measures pooled together, g = 0.169 (SE 0.106, t(38) = 1.583, p = .122, 95% CI −0.047 to 0.383); the discussion reports g = 0.10 for the same analysis (internal inconsistency, noted); academic outcomes were not pooled separately; designs were randomised or pre-post with a control, at least 10 sessions. The clause stays true but its basis is now stated exactly. Claim meaning unchanged (same or narrower); Status and kill line unchanged. Not a survival; does not reset C29's streak.
Evidence
4 linked sources: 3 supports, 1 limits (first-pass draft, pending human review). supports: Scionti et al. 2020, Melby-Lervåg & Hulme 2013, Kassai et al. 2019 · limits: Birtwistle et al. 2025