The Evolution of Water

In a recent TedTalk, MIT cognitive scientist Deb Roy gave a presentation entitled “The Birth of a Word,” based on a remarkable study he conducted over the last three years. Roy’s study was motivated by his interest in language acquisition. Specifically, he wanted to know how infants learned individual words over the course of their development. To do so, Roy wired his house with audio/video equipment and  recorded 90,ooo hours of video and 140,000 hours of audio (200 terabytes) to track how his son acquired English. Here is a clip that compiles all the instances from when his son tried to say the word “water,” over a six month stretch (listen for its gradual yet sudden transition from “gaga” to “water”).

Roy’s work is part of a growing body of research that tries to understand language acquisition, which is a hotly debated topic still in its infancy. In my last post I briefly touched on it by explaining why language is so metaphoric and interconnected. However, I realize that if we want to understand how language is acquired it is fruitless to just study syntax. It is like trying to understand planetary motion without mathematical equations; it’s easy to say that planets travel around the sun, but it entirely different explain why they do so. 

Unfortunately, there isn’t a Kepler for language acquisition, so I can’t offer anything novel here. However, it is worth contextualizing two contemporary theories that the language acquisition debate has spawned from. The first comes to us from Steven Pinker, who, in his 1997 book The Language Instinct, suggests that the ability to acquire language is genetic. He doesn’t explicitly state that there is a gene for language, “for any grammar gene that exists in every human being, there is currently no way to verify its existence” (322), but he does say that it is, “a distinct piece of the biological makeup of our brains” (18). So he is advocating that language is genetic in the same way that puberty or yawning is; there certainly isn’t “a gene” for either, but they are part of our genetic code nonetheless.

Park of Pinker’s project aims to figure out if all human languages are unified by some sort of “universal grammar,” (as Chomsky calls it) which holds that all “children must innately be equipped with a plan common to the grammars of all languages… that tells them how to distill the syntactic patterns out of the speech of their parents” (Pinker, 22).  The universal grammar debate is key for the language instinct hypothesis because if language really is instinctual, then you would expect it to be manifested similarly regardless of culture. Chomsky and Pinker have gone to great lengths to prove just that, but I will not get into the details for the sake of space (read Pinker’s book if your really interested).

In contrast, Stephen Jay Gould believes that thinking was an exaptation (a trait evolved for one purpose that later serves another pursue) that led to language. In his words, “natural selection made the human brain big, but most of our mental properties and potentials may be spandrels – that is, nonadaptive side consequences of building a device with such structural complexity” (The Pleasure of Pluralism, p.11). Evolutionarily speaking, Gould’s theory fits a bit better than Pinker who is faced with the Wallace problem, which asks how the Neolithic Revolution could have happened if brains had achieved its modern size roughly a million years ago. Simply put, language was too recent a phenomenon to be explained by natural selection, which is a much more gradual process. Gould accounts for this by saying that language is a byproduct of cognitive abilities that already existed.

Who is correct? Like so many things, the Pinker-Gould debate falls victim to dichotomy-fever i.e., our tendency to categorize things as being this or that. But that is not to say it is not helpful. As V.S Ramachandran explains, “neither of them is [correct], although there is a grain of truth to each… the competence to acquire [language] rules is innate, but exposure is needed to pick up the actual rules” (171). Like others, Rama believes that brains are language-ready, but do not have language built-in. This has been referred to as the still unidentified “language acquisition device,” and Ramachandran uses it to resolve Pinker and Gould’s contrasting views.

The next challenge is to understand exactly how genetics and experience work together to acquire language. This is part of Deb Roy’s project, which I think will turn out to be vitally important in the years to come. It is also a goal of many neuroscience labs out there today. And because they are all showing the brain to be more and more dynamic, it appears that an understanding of language acquisition will involve an understanding of the brain from a botton-up perspective. Unfortunately, this is a long ways off.