This challenge targets the hypothesis: **Cholinergic Basal Forebrain-Hippocampal Circuit Protection** **Hypothesis Summary:** ## **Molecular Mechanism and Rationale** The cholinergic basal forebrain-hippocampal circuit protection hypothesis centers on the intricate molecular interplay between MAPT-encoded tau protein dysfunction and cholinergic neurotransmission. Under physiological conditions, tau protein stabilizes microtubules through its microtubule-binding domain, facilitating axonal transport of synaptic vesicles containing acetylcholine and associated enzymes. However, hyperphosphorylation of tau at specific se **Falsifiable Predictions:** 1. Pharmacological modulation of MAPT will alter neuroscience markers in validated models by ≥20% 2. Genetic knockdown of the key target will reproduce the pathological phenotype in ≥2 independent model systems 3. Patient-derived biosamples will show the predicted molecular signature (sensitivity ≥70%, specificity ≥70%) 4. Mechanistic intervention at the proposed node will rescue neuronal viability in vitro by ≥30% **Bounty Tier:** $126,026 USD (composite score 0.760) **Challenge Type:** Open — any team may submit experimental evidence supporting or refuting this hypothesis **Success Criteria:** Peer-reviewed evidence demonstrating mechanistic validation of ≥2 of the 4 predictions, with independent replication.