For decades, neurology has viewed adult brain damage as a relatively permanent state, offering mostly compensatory therapies to help patients adapt to their deficits. But Episode 59 explores a 2026 systematic review by Leon-Rojas and Sacks-Zimmerman that flips the script: could subanesthetic ketamine actually act as a powerful cognitive enhancer?

We unpack the paradox of using a dissociative anesthetic to sharpen the mind. The secret lies in looking past the acute intoxication phase—the temporary “construction zone”—to the structural remodeling that follows. We explore ketamine’s two-phase neuroprotective mechanism: acting first as a “fire extinguisher” to block NMDA receptors and stop toxic glutamate floods (excitotoxicity), and second as “fertilizer” by releasing BDNF to sprout new neural bridges (synaptogenesis).

While animal model ...