Animals with Pre frontal Cortex?

skydivephil

Does anyone know how I can find out which animals have a pre frontal cortex and which do not?
I am interested becuase I came across a claim that seems highly suspicous printed in a book by a philosopher named Michael Murray.
He claims animals have pain but they are not aware of their pain becuase this higher levels of awareness requires a pre frontal cortex which most animals dont have.
I actually doubt the second claim too (that we can make such a direct relationshiop between consciouss awareness of pain and the pre frontal cortex) but thats going to be harder to research.
If anyone can shed some light on this it would be much appreciated.

Jobrag

Just a thought; but anyone who has accidently trodden on a cat's tail will be aware that cats feel pain.
Or look at this http://en.wikipedia.org/wiki/Cat_organ

skydivephil

Well of course I agree with you but Im looking for the tools to tackle the specifics of the claim.

apeiron

The prefrontal is found in all mammals. And some claim it has an equivalent in avian brains. It gets more complex as you move up the chain, of course. So the primate prefrontal has a definite dorsolateral area, for example, while in rats it is hard to distinguish.

As far as pain goes, the anterior cingulate cortex is more central to the feeling and noticing. The prefrontal cortex, as the "planning centre", then contributes a complexity of thinking about the pain. It can even help suppress awareness of pain by focusing attention on other more important things.

So all mammals would feel and be aware of pain. But what changes is the complexity of that perception - the ability to anticipate or recall, etc.

Perhaps evidence of the extra richness or complexity due to the expanded human prefrontal is the existence of masochism. I don't think that's been found in lesser brains so far!

skydivephil

Hi Aperion.
Thast great. Is there a source I might be able to use? Either a text book, a journal article or a quote from someone who has some authority in the field? Im thinking of making a little youtube film regarding this bizarre claim (animals dont feel pain) and i do need reliable sources. Cheers

Number Nine

The claim is more complex than you're making it out to be. Pain is a physical sensation shared by most animals, yes, but there's also a subjective conscious experience of pain that may or may not be felt in all of those same animals. Have you ever received morphine for extreme pain? Quite a number of people who receive morphine don't report a ceassation of pain, they just report that the pain no longer bothers them (i.e. their subjective experience of pain is no longer extremely negative). Subjective conscious experience is associated with considerably more advanced brain development than the mere sensation of pain (though not necessarily just the pre-frontal cortex, which would tend to be more involved in abstract and high level information processing).

apeiron

I just said it was complex.

apeiron

You could try.... http://www.ncbi.nlm.nih.gov/books/NBK32655/

Pythagorean

Amphibians effectively have frontal lobes too. They're very small, but the are required by IACUC to be removed before performing physiology experiments. So according to IACUC, amphibians can otherwise experience/feel pain.

for those who have never heard of IACUC:
http://www.iacuc.org/aboutus.htm

To answer your general question "Does anyone know how I can find out which animals have a pre frontal cortex and which do not?" you are in luck! It is very rare for such complex organs to evolve convergently, so everyone with a frontal lobe today probably came from a common ancestor.

atyy

Is there consensus?

http://research.yerkes.emory.edu/Preuss/RWA.html
Preuss, T. M., 1995. Do rats have prefrontal cortex? The Rose-Woolsey-Akert program reconsidered.Journal of Cognitive Neuroscience, 7:1-24.
"A re-evaluation of rat frontal cortex suggests that the medial frontal cortex, usually considered to homologous to the dorsolateral prefrontal cortex of primates, actually consists of cortex homologous to primate premotor and anterior cingulate cortex. The lateral MD-projection cortex of rats resembles portions of primate orbital cortex. If prefrontal cortex is construed broadly enough to include orbital and cingulate cortex, rats can be said to have prefrontal cortex. However, they evidently lack homologues of the dorsolateral prefrontal areas of primates. This assessment suggests that rats probably do not provide useful models of human dorsolateral frontal lobe function and dysfunction, although they might prove valuable for understanding other regions of frontal cortex."

http://www.ncbi.nlm.nih.gov/pubmed/18835649
Wise SP. Forward frontal fields: phylogeny and fundamental function. Trends Neurosci. 2008 Dec;31(12):599-608.
"The largest part of the primate prefrontal cortex has no homolog in other mammals. Accordingly, it probably confers some advantage that other mammals either lack or attain through the function of other structures. Yet, this advantage remains enigmatic. This is not so for other parts of the cortex. For example, certain visual areas encode, represent and store knowledge about objects. By analogy, perhaps the primate prefrontal cortex encodes, represents and stores knowledge about behaviors, including the consequences of doing (or not doing) something in complex and challenging situations. The long list of functions often attributed to the prefrontal cortex could contribute to knowing what to do and what will happen when rare risks arise or outstanding opportunities knock."

Number Nine

That's pretty consistent with what I see in the literature re. animal models of PFC function. They're fairly popular models of anterior cingulate function (I'm buried in the ACC literature at the moment), but outside of the ACC and some motor areas, most of the PFC work seems to take place on primates.

This is actually relevant to the OP's question: Rats are one of several animals that are candidates for meta-cognition (i.e. self-awareness; "thinking about thinking"). We could thus reasonably speculate that they can experience pain subjectively to some extent, and yet their PFC is considerably less developed than ours (though, more developed than most other animals).

apeiron

This review may help clear up that point. It is possible to differentiate between the subjective intensity of a pain as mapped by the somatosensory cortex, versus the subjective feeling of the unpleasantness of that pain as mapped by the anterior cingulate.

http://bscw.rediris.es/pub/bscw.cgi/...modulation.pdf

The prefrontal clearly contributes even more to the whole pain experience on top of this, quite probably wrapping the extra level of self identification around everything - 'this is me that's hurting' - but the ACC looks central to regulating the feelings of suffering.

Pythagorean

Another source: From John Kaas, "Evolutionary Neuroscience", Chapter 43: Frontal Cortex Evolution in Primates:

[my comments in square brackets]
(there's much more interesting discussion in this book, but I don't want to violate copyright by carrying on too long).

http://books.google.com/books?id=dTE...imates&f=false

compared to:

"The largest part of the primate prefrontal cortex has no homolog in other mammals"

I find these bolded statements to be consistent with each other because they answer slightly different questions.