Multiphasic memory in O. vulgaris

[hallucigenia]

A couple of cool posts on Cephalove discussing the nature of memory in Octopus vulgaris:

Short and long-term memory in cephalopods
Memory, observation, and consciousness in Octopus Vulgaris

The upshot of the two posts is that there appears to be good evidence for multiphasic memory in octopuses, but also that it doesn't work exactly the way it does in humans and other vertebrates with a working-memory -> long-term-memory model. Instead, the vertical lobe appears to handle something analogous to working memory, on the scale of hours, but the long-term memory system seems to form memories entirely independently of this! And, perhaps even more amazingly, octopuses with functioning vertical lobes also experience faster memory fading! This is some crazy stuff, dudes. Highly recommended reading.

Also, the latter discusses observational learning, which apparently O. vulgaris can do. Pretty neat.

 

[DWhatley]

I will definitely read the articles later tonight. I have often mentioned that I think there is something odd about the way they remember things and that I don't think the researchers have identified their memory capacity correctly. One of the things I THINK we see is a memory loss that is temporary. Often they will "learn" something or show a consistent behavior (particularly when interacting with humans) and then seem to forget for three days or so but then suddenly remember. This might coincide with the short term and independent long term concept you mention but I will read the paper to see if anything they have officially observe would explain this behavior.

Just started the paper and I am quite sure this assumption is incorrect (actually opposite of what happens)

In general, if people cannot remember something for a short time, they cannot thereafter remember it better after a long interval - it is simply gone from the system.

I can't site a paper but I was involved in a graduate study (you the kind you HAVE to participate in as part of a class that is unrelated to the study so that the other students will have available guinea pigs) where they were proving that very short term memory retains little but over a period of time (granted the times were something on the order of immediate and then 30 minutes and not hours and days) memory is better. The test was simple, walk into a room, leave the room, record what you saw, wait 30 minutes and write what you saw again.

Also note that he references nautilus memory studies by a certain Ms. Crook (unfortunately no link) who is currently blogging on her new studies about squid.

 

[CaptFish]

Good stuff I'm reading it now.


The link to Robyn's paper is there.

but here it too:

Crook, R., & Basil, J. (2008). A biphasic memory curve in the chambered nautilus, Nautilus pompilius L. (Cephalopoda: Nautiloidea) Journal of Experimental Biology, 211 (12), 1992-1998 DOI: 10.1242/jeb.018531

 

[Cephalover]

Sorry about skipping the link. I use researchblogging.com to format my citations, and if it doesn't spit out a link, I usually don't bother to fix it.

The whole deal where ablating the vertical lobe improves memory retention just blows my mind. I think J. Z. Young (c'mon, memory, don't fail me now) put forth a theory that the vertical lobe is involved in revising the sensory memory store, and so its activity is responsible for the time-dependent degradation of memories - it's essentially an active "forgetter". Therefore, when you take it out, the octopus loses its ability to forget what it's learned (which might be different from getting better at remembering it, as far as the neural processes it might imply.)

 

[DWhatley]

The forgetter idea is interesting. I recently read that we recreate memories and that they are not only not stagnant but that they can be changed. The premise is that we have to continually rewrite memory to remember it and that we are more or less remembering the memory and not the original incident. Here is a piece by Ed Young's (Not Exactly Rocket Science) describing the research.