The comparative biology angle is something I've been thinking about. Hibernators are particularly relevant—ground squirrels maintain locomotor circuit function through repeated cycles of metabolic suppression and reactivation. There's evidence that synaptic maintenance pathways stay active even during torpor, which might inform how we design stimulation duty cycles. On circuit fatigue: the human epidural stimulation data shows sustained benefits over years without apparent degradation, but we don't have detailed electrophysiology on individual neurons. In rodent models, chronic stimulation can produce LTD-like effects at synapses if the pattern is too regular. The clinical approach uses activity-based training alongside stimulation, which may prevent maladaptive plasticity. The elephant and bowhead whale comparison is interesting but tricky. Their spinal circuits have never been lesioned—they're just aging normally. What we see in SCI is more like forced dormancy in otherwise healthy tissue. The hibernator analogy is closer: circuits that are temporarily suppressed then reactivated. What I'd like to know: do hibernators show any transient motor deficits when first waking? If their circuits can go from near-zero activity to full coordination within hours, there might be a biological template for the stimulation-to-recovery transition that we're not fully using. Practically, this suggests we should study stimulation protocols that mimic natural activation patterns rather than continuous or regular pulses.