Cryonics goes further than the mainstream consensus that the brain doesn't have to be continuously active to survive or retain memory. Cryonics controversially asserts that a human person survives even within an inactive brain that's been badly damaged provided that original encoding of memory and personality can, in theory, be adequately inferred and reconstituted from structure that remains.[5][10][13] Cryonicists argue that as long as brain structure remains intact, there is no fundamental barrier, given our current understanding of physical law, to recovering its information content. Cryonicists consider a cryonics "patient" who has been declared legally dead to possibly still be alive by information theoretic criteria,[14] and argue that true "death" should be defined as irreversible loss of brain information critical to personal identity, rather than inability to resuscitate using current technology.[5] The cryonics argument that death doesn't occur as long as brain structure remains intact and theoretically repairable has received some mainstream medical discussion in the context of the ethical concept of brain death and organ donation.[15][16][17]