This challenge targets the hypothesis: **Therapeutic Window Exists Because Amplified Signals (Not Baseline) Drive Pathogenesis (H3)** **Hypothesis Summary:** G2019S basal RAB10 phosphorylation elevation may be secondary; true pathogenic driver is amplified stress-response signaling. Partial LRRK2 inhibition sufficient to normalize stress-induced spikes while preserving necessary baseline functions. LRRK2 knockout mice viability supports non-essential baseline hypothesis. Age-dependent neurodegeneration in knock-in mice suggests stress-dependent pathology rather than chronic baseline elevation. **Falsifiable Predictions:** 1. Pharmacological modulation of LRRK2 will alter neurodegeneration 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:** $128,000 USD (composite score 0.780) **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.