Babel's Dawn

Autism and Joint Attention

Joint Attention is often thought to require catching another's eye and a willingness to look in the eye.

It has long seemed to me that if we understood the origins of speech, we would better understand what it is that sets humanity apart from the rest of the animal kingdom. Many people come at the issue from the other end. They claim to identify what it is that sets humanity apart, and then try to relate their conclusion to speech. The proposed X factor might be rational thought, recursive syntax, having a theory of mind, symbolic thinking, tool using, etc. Sometimes the proposed X turns out to exist elsewhere in the primate world, but even when the assumption stands, the approach turns the problem of speech origins into a two step affair:

1. Explain the origins of X, and,
2. given X, explain the origins of speech.

I have tried to simplify the problem by coming at from the other end. Learn something about the origins of speech and see what X emerges. After last week’s post (here) it seems to me that an X may have emerged.

How the Brain Supports Conversation

The attention triplet has appeared several times on this blog, and can now be illustrated as including the interaction of different brains.

A visitor to my blog, Janet Kwasniak, tipped me to an article reporting a possible neurological basis for humanity’s unique powers of joint attention. Regulars on this blog will know that it leans toward an attention-based view of language. My working assumptions are that words are tools for piloting attention and that speech requires a speaker and a listener paying joint attention to a topic. Thus, the evolution of speech required the evolution of joint attention, so I was delighted when Janet told me about an article in last October’s Current Directions in Psychological Science, “Attention, Joint Attention, and Social Cognition,” by Peter Mundy and Lisa Newell (abstract here).

The article holds that human brains have two distinct attention systems which, when working together, produce joint attention. The older system, located in the rearward (posterior) part of the brain is reflexive and tracks external stimuli. When something moves, this system responds. A separate, voluntary system is located in the brain's frontal (anterior) region and pays attention to one’s own purposeful behavior.

These systems exist in humans and chimpanzees, but in humans the two can be integrated into one unified system that permits joint attention. For example, two people are seated in a restaurant booth facing one another. Suddenly the posterior attentional system of one customer directs his eyes toward the sight of a waiter pouring soup on a diner’s head. Meanwhile the customer uses his anterior system to say to the companion, “Will you look at that,” and point to the unexpected scene. Joint attention comes from the capacity to integrate these two, separately-developed brain systems.

The Rise of Untranslatability (Part 2)

Red ochre has been used to reveal some untranslatable aspect of the user's identity since before there were Homo sapiens.

Inspired largely by reading Tolstoy’s Anna Karenina and an essay on the problems of translating Dante into Arabic (abstract here), last week’s post (here) asked when and why did languages become untranslatable? This week proposes an answer.

The Origins of Attention

Leopard at Seronera. Could it be that they don't have enough of an attention span to hunt in packs?

Language is unusual in the way so much of it functions on the conscious level. Both speaker and listener (if all goes well) are conscious of what is being said and where their attention is directed. Speech has unconscious supporting elements, but the point of an exchange is to direct and share conscious awareness of some topic. Presumably, it is that shared awareness that long kept philosophers blind to the unconscious elements of behavior, but consciousness itself is such a hazy concept that it had been hard to build on the fact of its importance. So I was glad to see in the Oct. 15 issue of the New Yorker the physician/writer Jerome Groopman discussing an emerging medical definition of consciousness (article available online). The piece provides an introduction to the mental prerequisites for speech’s evolution.

Common Ground

Boston common serves as the metahphor for the shared psychological abstraction where speakers focus their joint attention.

The current (May/June) issue of Child Development has a series of articles on the role of pointing and evolution/development of language. The lead article in the series is “A New Look at Infant Pointing” (abstract here) by Michael Tomasello, Malinda Carpenter, and Ulf Liszkowski. It is largely a repeat of ideas discussed on this blog recently under the title Infant Collaborators. The basic thesis discuss there is that speech is a method for collaborating on a common psychological ground, and that a useful tool in this collaboration is pointing. Humans, according to this view, are unique for sharing purposes and meanings. Thus, the central proposition of the Child Development series is already familiar to regular readers of this blog. The most important contribution of the Child Development series is the range of expert criticisms and extensions of this idea that are offered.

Infant Collaborators

Speaking of collaboration, I found this cartoon over here at the Goodwill site.

The central dispute in today’s study of speech origins concerns the nature of speech itself. The classic position has been that it is a system for expressing and organizing symbolic meanings. Much of twentieth-century philosophy was devoted to figuring out what symbols were and how they worked. Last week’s post on the variety of gestures that chimpanzees and bonobos make reported on a new report arguing “that gesture has become a serious candidate for the origins of expressing ‘symbolic meaning in early hominins.’”

This week’s post looks at the rival understanding of speech, one that says it is a system for directing and sharing attention. An article about “Shared Intentionality” (abstract here) published earlier this year by Michael Tomasello and Malinda Carpenter in the journal Developmental Science contrasts infant/toddler behavior with that of chimpanzees. Unlike the study of gestures, this article finds that there is a very serious difference between human and ape behavior.

More on What Speech Is

Yesterday's post looked at theoretical, empirical, and pragmatic reasons for thinking of speech as an expansion of the powers of joint attention rather than as a system for communicating ideas. It was beginning to run a bit long, so I'm continuing with other pragmatic reasons on this post.

Speech Evolution

Part of the mystery of the origins of speech has been the absence of any likely pathway. We could imagine a series of steps: speaking words, speaking phrases, speaking sentences, but at no point could we imagine a reason for making any of these steps. Joint attention provides a reason.

What Speech Is

This week’s posts are trying to make sense of what this blog has learned since it first appeared last September.

Language is usually defined as a system of communication, which seems obvious enough until you think about it in evolutionary terms. Ape communications consist of involuntary vocalizations. Among humans such vocalizations include things like laughter and sobbing, activities no one is likely to confuse with speech, precisely because they are involuntary. It would be hopelessly paradoxical to deny that language is used to communicate, but at least we can deny that it is anything like ape or computer communications.

The Talking Sociopath

If love makes the world go round, why hasn't selfishness put a stop to the spinning?

A mystery of speech that keeps poking its head into this blog is that it is profoundly unselfish. If you take Darwinian concepts literally (and you should), there seems to be no benefit in blabbing useful secrets. If Joe wants to tell where the wild figs grow, Jacks is happy to listen, but why should Jack respond by telling of an even better fig garden? Selfish rationality should result in everyone keeping mum. Speech should not evolve.

This question is never far from my mind, and comes forward now with double strength because I have been reading a series of articles that appeared in last June’s Behavioral and Brain Sciences (lead article here) on the evolution of cruelty in human affairs. Frankly, the amount of stark cruelty it depicts—ranging from hyenas eating wildebeest alive, to Caesar Augustus amusing himself by watching boxers fighting with a metal studded gloves—is a bit hard to take. But the point is serious. Cruelty we have everywhere. How can something based on its opposite appear and persist in such a world?

The Strangest Taste

This blog has been underway for almost half a year now and, as every reporter knows, there is no better way to find out what is happening in some corner of the world than working a beat. I suppose the first surprise has been that there really can be such a beat. There is a steady flow of news that is relevant to the origins of speech.

Another surprise has been in the range of opinions. I was surprised to find some scholars who still look on speech as a cultural invention, like writing, and then I was surprised again to find scholars who, while accepting evolution and speech’s biological origins, doubted that natural selection had much to do with the story.

But most of all, I have been surprised by three themes that repeat themselves. Roads keep pointing back to Homo habilis. Communities of sharing and emotional bonds never stray far from the spotlight. And the keystone that keeps holding up the structure is our odd taste for joint attention.