They list 8 separate empirical criteria for sentience, and evaluate them each in detail for the different species involved.
1) possession of nociceptors;
2) possession of integrative brain regions;
3) connections between nociceptors and integrative brain regions;
4) responses affected by potential local anaesthetics or analgesics;
5) motivational trade-offs that show a balancing of threat against opportunity for reward;
6) flexible self-protective behaviours in response to injury and threat;
7) associative learning that goes beyond habituation and sensitisation;
8) behaviour that shows the animal values local anaesthetics or analgesics when injured.