The Best Kind of Aging Brain

Cuttlefish, with their blimp-shaped bodies and eight squiggly arms, don’t age like people do. Sexual maturity tends to come late for them—about three-quarters of the way through their two-year lives, the rough equivalent of a human hitting puberty in their 60s. The geriatric cephalopods will then spend several weeks on an absolute bender, coupling up with as many partners as they can. Only after the close of these frenetic sexual bonanzas does true decrepitude come to claim them: Their feeding tentacles go limp; their appetite deserts them; their color-changing skin flickers like a television on the fritz. The animals pivot almost instantaneously from their sexual prime into the throes of infirmity, and within days, they are dead. “They really go out with a bang,” Alex Schnell, a cuttlefish biologist at the University of Cambridge and the Marine Biological Laboratory, in Massachusetts, told me.

Before this rapid denouement, though, that common cuttlefish () can still form and retain crystal-clear memories of personal experiences just a month before their death. They can catalog the ,,and of recent events, and use that knowledge to inform their actions in the present. It’s an animal approximation of what’s called episodic memory in humans, an ability that’s often billed as a sort of mental time travel that allows creatures to relive past experiences. For us, episodic memory usually starts to . But the cuttlefish version appears to persist deep into their golden months. “I’m not familiar with any other animal model that has shown episodic-like memory still intact” this late in life, Gabriel Nah, a neurobiologist who studies rat memory at Indiana University and wasn’t involved in Schnell’s work, told me.