I think a more obvious candidate is self-selection. People with known mental issues that want a pet are wise to choose those that demand less maintenance. It's

I think a more obvious candidate is self-selection. People with known mental issues that want a pet are wise to choose those that demand less maintenance. It's hard to go walk the dog while undergoing a mental breakdown. Cats, on the other hand, don't require people to walk them, and are mostly self-cleaning. They are a safer pick for people whose routines are subject to sporadic disruption.