Developmental Potassium Channel Maturation Enables Robust and Flexible Learning

SUMMARY Neural maturation must preserve flexible state dynamics while preventing those dynamics from becoming unstable, unreadable, or mismatched to learning. Here, I identify KCNH7, encoding the ERG3/Kv11.3 potassium channel, as a maturation-associated candidate regulator of such operating regimes. Public developmental, single-cell, and Patch-seq analyses linked KCNH7/ERG3 to late postnatal expression and passive-state electrophysiological axes. In conductance-based Purkinje-cell models, ERG3/KCNH7-like conductance increased the threshold for tonic firing while broadening pre-tonic response classes and enhancing target-specific rhythmic recruitment, indicating a regime shift rather than a simple excitability brake. KCNH7-inspired adaptive dynamics stabilized spiking learning and reshaped high-load associative retrieval beyond scalar threshold or temperature control. In recurrent conductance reservoirs, ERG3/KCNH7 scale and half-activation voltage tuned driven dynamical regime, spike-state versus voltage-state memory, and temporal-context-dependent prediction. Under degraded state transmission, moderate WT-like ERG3/KCNH7 conductance converted a vulnerable high-dynamic baseline into a low-fidelity support regime. Public in vivo population and behavioral analyses further supported the view that maturation- and disease-related phenotypes can be interpreted as alterations in operating-regime control rather than simple changes in activity or sensory performance. These results support KCNH7/ERG3 as a model case for linking ion-channel maturation to stable yet flexible neural computation.