Behavioral and neurophysiological evidence suggests affective pain experience in octopus
https://www.cell.com/iscience/fulltext/S2589-0042(21)00197-8Feel the light – sight independent negative phototactic response in octopus' arms | Journal of Experimental Biology
https://jeb.biologists.org/content/early/2021/02/01/jeb.237529Octopus in quiet and active sleep states [video] | EurekAlert! Science News
https://www.eurekalert.org/multimedia/pub/259718.phpOctopuses Have a Secret Sense to Keep Their 8 Arms Out of Trouble - The New York Times
https://www.nytimes.com/2021/02/20/science/octopus-arms-light.htmlOctopuses can feel pain both physically and abstractly - The Academic Times
https://academictimes.com/octopuses-can-feel-pain-both-physically-and-subjectively/Proprioception | Definition of Proprioception at Dictionary.com
https://www.dictionary.com/browse/proprioceptionSleeping Octopuses May Have Dreams, But They're Probably Brief | KASU
https://www.kasu.org/2021-03-25/sleeping-octopuses-may-have-dreams-but-theyre-probably-brief