Do cephs sleep?

Octavarium

Wonderpus
Registered
Joined
Feb 9, 2008
Messages
235
I assume so because of their advanced brain, but I can't find out much on this issue. It appears my hummelincki goes to the same area every night after 12 and doesn't move at all or react to my finger (when blue LEDs are on until 12:30). Does anyone know about the sleeping habits of different cephs?
 

Jean

Colossal Squid
Registered
Joined
Nov 19, 2002
Messages
4,218
'tis hard to say. I'm not sure anyone has done sleep studies on octopus. Certainly they seem to have a definite resting phase. Even in fish there is huge argument on whether or not they sleep, some say yes some say no. There is a lack of features in brain wave activity (such as REM sleep) that you would expect to see in a sleeping human.....but should we expect to see the same patterns in a creature that is so very different to us?
 

monty

TONMO Supporter
Staff member
Registered
Joined
Mar 8, 2004
Messages
4,884
Although ceph brains are very complex and can do impressive things, they are organized so differently from vertebrate brains I would be surprised if they had something exactly like sleep, and very curious about the similarities and differences. I certainly don't think that the argument about "advanced brains" needing sleep is necessarily valid: our last common ancestor was some precambrian thingie somewhere between a leech and a limpet, probably something worm-like... I doubt it needed to sleep, so sleep would have evolved separately... which would imply that it's somehow fundamental in advanced intelligence, whereas I think it's more likely that it's a quirk of the vertebrate nervous system... As Jean says, I'm not sure it's clear that fish (or amphibians, or even all reptiles) sleep-- this only lists mammals, and this has some comments on birds and mammals, but not reptiles, amphibians, and fish showing REM sleep signs (although they have a rather naive interpretation of birds descending from reptiles: my impression is that modern classifications have birds descending from dinosaurs having split off from the cold-blooded reptiles quite a bit earlier.)

Anyway, as in the discussion of cephalopod consciousness it's very interesting to consider the similarities and differences in diverse animals with advanced brains, so if cephs are found to sleep in ways that correspond to mammal sleep, it would be very interesting to compare-and-contrast the elements that are similar and different: is sleep important for converting short-term memory to long-term memory? Is this necessary for any memory system based on nerves?
 

DWhatley

Kraken
Staff member
Moderator
Joined
Sep 4, 2006
Messages
20,999
Without being able to define sleep, observation of inactive times will have to do. Both my Mercs and my Hummelincki sleep on a regular basis at regular times taking a pose and location different from their active time habits. The Mercs do not always choose the same place but do leave the open water for a sheltered environment and take the same position. The Hummelincki takes both the same place and position in his/her inactive state.
 

Brown

Hatchling
Registered
Joined
Feb 18, 2004
Messages
5
We now have reasonably strong evidence (behavioural, attentional and electrical) that Octopus do a kind of sleep. See the paper

Brown ER, et al 2006 Behav Brain Res.;172(2):355-9.

Octopus vulgaris maintained under a 12/12h light/dark cycle exhibit a pronounced nocturnal activity pattern. Animals deprived of rest during the light period show a marked 'rebound' in activity in the following 24h. 'Active' octopuses attack faster than 'quiet' animals and brain activity recorded electrically intensifies during 'quiet' behaviour. Thus, in Octopus as in vertebrates, brain areas involved in memory or 'higher' processes exhibit 'off-line' activity during rest periods.

If you would like a copy of this paper I can forward it

E
 
Joined
Nov 20, 2002
Messages
1,073
Oh my -- had I done a keyword search before initiating the new To sleep, perchance to dream thread, I would've continued the discussion on this one instead! At any rate, this old thread is particularly helpful and relevant to my query, and if anyone is following it, please continue the discussion on the new thread.... this is a great subject!
 

Decay

Blue Ring
Registered
Joined
Oct 19, 2008
Messages
37
does anybody know how well, if at all, octopuses adjust to shift work? can they easily bounce around their inactive period and match the owner no matter what the routine, or to they need a period of adjustment? im not after any real scientific studies, just curious about wether anyone here works shifts, and how their animal coped.
 

Latest Posts


Top