I have to make a correction. In my post on LeDoux’s views on consciousness and emotions, I made the following statement:
Anyway, LeDoux states that there is “no convincing” evidence for instrumental behavior in pre-mammalian vertebrates, or in invertebrates. In his view, instrumental behavior only exists in mammals and birds.
As it turns out, this is is wrong. In his hierarchy, he makes a distinction between instrumental learning that is habitual versus goal-oriented (action-outcome). On my first pass reading his description of this, I assumed that a habit could only form after initial goal-oriented learning. But while checking back on some details, I realized he actually describes learning that leads directly to habits without the goal-oriented stage.
In practice, an animal may engage in random trial and error behavior, some of which leads to a result that reinforces the behavior. If repeated often enough, a habit develops. Habitual learning can be distinguished from goal-oriented behavior by seeing what happens when the reward is later removed. In goal-oriented behavior, the behavior quickly ends, but habits tend to persist for a while. (Which of course is what a habit is all about.)
Habitual learning is much slower than the goal-oriented version, much more stimulus-response driven, far less flexible, but apparently it does happen. I’ve dug around a bit in the literature, and it appears to be widely accepted.
So to correct the statement above, LeDoux does see instrumental learning as existing in all vertebrates, not just mammals and birds. However, it is the goal-oriented learning he doesn’t see as having been demonstrated in pre-mammalian vertebrates. Fish, amphibians, and reptiles he sees as only having the habit forming version.
I’m not sure what to make of this habitual type of instrumental learning. Habits by and large appear to be largely nonconscious, so would learning them be as well? Of course, LeDoux doesn’t even see goal-oriented instrumental learning as conscious, so in his view this distinction only amounts to different levels of sophistication in nonconscious learning.
As I mentioned in the other post, Feinberg and Mallatt, in The Ancient Origins of Consciousness, do see instrumental learning as indicating what they call affect consciousness, aka sentience. And the indications of instrumental learning in all vertebrates drive their conclusion that all vertebrates are sentient.
But Feinberg and Mallatt don’t get into the distinction between habit and goal-oriented instrumental learning. So I don’t know if this is a difference they overlooked, disagree with, or accept but see even the habit learning version as indicating affect consciousness. A clue might be that, when deciding on their behavioral criteria for affect consciousness, they ruled out “persistence in pursuit of reward” as a criteria, because it “could reflect aroused but unconscious habits.” (Emphasis added.)
A case could be made that even in habit learning, if not in habit persistence, there needs to be a valence, but both LeDoux and the literature make clear this happens in a representation or model free manner, which may not leave much room for it to fall even in primary consciousness.
A question then is, can goal oriented behavior be demonstrated in fish, amphibians, reptiles, or invertebrates? LeDoux doesn’t think so, and notes that habit and goal-oriented behavior look alike without explicit tests to distinguish them, although maybe the rapidity of learning might provide clues.
So, this may complicate my new hierarchy, particularly the level where affects begin. I’m going to have to give this some thought, and additional research, but wanted to get the correction out.