Sea Lions and Parrots: Smaller Brains, Equivalent Abilities

Sea Lions and Parrots: Smaller Brains, Equivalent Abilities Psych 1090 Lecture 15

A few years after Herman began publishing his work on the dolphins, Schusterman decided to see what a smaller-brained marine mammal might do….a sea lion Schusterman was also trained in the behaviorist tradition

And, to make sure that his techniques would match those of Herman, he went out and actually studied with Herman for awhile And decided to use the gesture language because it required less hardware

He trained a sea lion, Rocky, to do most of the same things that Ake and Phoenix had learned to do with basically the same grammar to act on various items—“frisbee over” meant jump over the frisbee And also taught some relationals

So, like the dolphins, Rocky could understand when to take the frisbee to the surfboard and when to do the reverse action Unlike Herman, Schusterman also taught Rocky relational terms… Bigger/smaller, lighter/darker

Relational terms are really important because they are totally context dependent As we talked about in earlier lectures, what is bigger on trial 1 can be smaller on trial 2 so the subject cannot answer with respect to absolutes;

the subject has to understand the concept that is being tested And, of course, the subject has to be able to transfer to new exemplars without any training And Schusterman and Herman were different in other ways…

They got into quite a battle about ‘grammar’… Herman insisted that what his dolphins were doing was grammar… In fact, one of the reasons he started the research was to show that a nonhuman could learn grammar

But Schusterman argued—correctly—that what had been learned was rule-governed behavior… The first step toward grammar, but nothing quite as complex as what humans use

As an aside, birds engage in such rule-governed behavior in their complex songs and any animal, bird or mammal, and like early humans, that combines a vocalization with a gesture in a standardized manner

is engaging in a primitive grammar: A standardized rule-governed behavior that enables efficient transmission of information They then continued to “duke” it out, arguing over what is or is not grammar in their subjects, Using “anomalous” commands

Now, we talked about the anomalous commands for dolphins awhile back and mentioned that Lana would ‘erase’ anomalous sentences from her computer and we saw that Kanzi would carry out semantically stupid actions that were grammatical…

Only Schusterman tried to make sense of all this in terms of conditional discriminations and something called equivalence class formation The latter is, according to some researchers, the basis for human linguistic competence

Now, we’ll get back to equivalence when we discuss the results of Schusterman’s experiments But now is probably a good time to introduce the concepts BRIEFLY and why it is thought to be important And, as usual, a source of controversy!

In some ways, equivalence is just a special form of transitive inference Only instead of using, e.g., “bigger/smaller”, it uses “equal to” So, if A=B, B=C, A?C

Which suggests that any animal that can do TI should very easily be able to understand equivalence Of course, as with TI, a lot has to do with how the subject is trained or exposed to the stimuli And, of course, there are fancy terms for the various relationships

We’ll get to all that later…for now all we need is to understand what Schusterman means by “functional equivalence”… Which is basically that Rocky understood that some signs related to objects, some to actions and some to attributes

In human language terms, nouns, verbs, and adjectives Note that Schusterman is looking at a very simple form of equivalence here… Just hierarchical categories of how the signs relate to the sea lion’s world

And, an aside…at one point, Schusterman used two-handed actions for one type of sign and one-handed actions for another… I’m not sure that he kept to this, but at least in the beginning it would have been an important cue simplifying what the animal had to learn…

So, in the paper on anomalous sentences, the issue was how Rocky would respond If the sign from one functional class was placed in the spot normally reserved for another functional class or if something was missing in the sentences she was given

Basically, she would balk if given something that didn’t make sense though sometimes she’d do what she could with what she was given Suggesting that she understood enough to know that these weren’t right

Interestingly, she balked appropriately if, for example, an object was missing but did what she could when a modifier was missing Of course, she had learned to work with objects before they had been modified… which may have mattered…

Also is not clear if her dropping first anomalous modifier had to do more with memory… But anyway you look at the data, Rocky had some idea about what was going on… She never performed randomly on nonlabeled items

But whether she had learned a real syntax was still not clear… Was she balking when an action was missing because of syntax or just because she had been trained to station until she saw a verb?

In terms of conflicting modifiers, Rocky did about 3/4 with respect to recency… Given that only a fraction of trials were reported, this was probably statistically relevant… But not as strong as argued in the discussion

And, of course, as noted by Schusterman, all that Rocky did was to enable her to get the most fish per session So, were these actions that she performed meaningful in any real sense? Or just actions to be performed in particular ways for food?

Such questions can, of course, never really be answered…. But they were asked by everyone who argued against the results of these ‘animal language’ studies And, of course, the arguments between the researchers didn’t help

Now, such arguments were, in one sense, very good and important Because a field can’t grow and we can’t learn from our mistakes if the mistakes aren’t found The issue is whether there should be a chance to fix the mistakes and continue

I didn’t choose to assign the papers where Herman and Schusterman go after each other They are referenced in the papers that have been assigned for those who are interested I’ll just briefly go over the bit we did read…

In many ways, Rocky did not differ all that much from the dolphins Although Schusterman does see differences…. Primarily with respect to reinforcement issues…

As stated, dolphins were ‘paid’ to guess and the sea lion was not which again brings into focus how different types of training regimes result in different outcomes And the importance of experimental design

While I don’t see either set of experiments as really telling us all that much about the actual ways in which the animals process information… I do see that there isn’t too much basis for a pure linguistic interpretation

Just like the starling-recursion discussion … IF you argue that failure on a task demonstrates lack of linguistic knowledge Then you have to accept that success does demonstrate linguistic ability…

But the real issue is whether the task really was the crucial one… Note, the issue is not whether the CONCEPT was the crucial one… It may still be…. But the task chosen to represent the concept

AND exactly how the task is taught to the subjects e.g., the tamarins were exposed to the task and the starlings taught… And these are the same issues here for the dolphins and sea lions

And this brings us back to the equivalence issues…. And whether one can actually analyze language from the standpoint of equivalence Or if equivalence is one of several issues

So, let’s talk about what all the terms in equivalence mean and how they might relate to language…. for humans and nonhumans alike

So, we start with reflexivity, A=A Which is just another fancy term for identity match-to-sample And, we have seen, most animals are pretty good a learning that and transferring it to totally novel stimuli

Although for some animals what is shown during transfer is just a savings in trials needed to ‘get it’ compared to the number of trials needed to learn the original task But, basically, it isn’t rocket science

The next part is symmetry and that is a bit more difficult Because not only is it a conditional relationship… that is, “if A do B”, but also “if B do A” Many nonhumans have trouble with symmetry

But nonhumans can indeed be trained to respond to symmetry It doesn’t however simply emerge from their initial if A then B knowledge And it really isn’t entirely clear that it emerges for children either

Although various studies suggest that it emerges much more easily for children than for nonhumans

And, of course symmetry is what underlies a lot of what language is about…. Because comprehension-production require symmetry…. And, as we saw, sometimes animals taught only production couldn’t comprehend and vice-versa

The animals’ abilities may have had more to do with the way they were trained than with their innate abilities But you can see why the issue of equivalence is so critical to language A subtle point that is not addressed except by Premack, however,

Is whether even knowing that A and B are related by symmetry means that A is a symbol representing B You could see how just accepting that A and B are interchangeable doesn’t mean they are symbolic representations

Think of it this way…I can give you a token for a cup of coffee, or vice versa But the token doesn’t represent that cup of coffee Unless I know otherwise, the token can instead represent $1

And that’s one of the big issues in the idea of training many equivalences…. Because many things can, for example, cost $1, but the $1 doesn’t really represent them… Except in an odd, basic sense

But let’s go on to transitivity that is the equivalence form of TI… So that the subject, trained on A=B and B=C can, without training, understand that A=C But, again, are we talking about real symbolization or not?

We can see how it might relate to language… in the sense of “key” (the vocal label) = KEY (the written label) = = “key” , etc

But, as with the $1 example, you can see how the issue becomes clouded… Now, some researchers argue that equivalence is a prerequisite for language Others argue that language is a prerequisite for equivalence…

Sea Lions and Parrots: Smaller Brains, Equivalent Abilities