Sign language, ASL, and baby signing

September was National Deaf Awareness Month. I tried to post this piece before the month ended, but alas! Better late than never. I’d like to discuss and dispel some of the many misconceptions around signed languages. Here are a few of the most common:

  • Sign language is universal – there is only one
  • Sign languages are not “real” languages
    • They’re simpler and easier to learn than spoken languages; they’re just gestures, or body language, or pantomime
    • They’re not as complex as spoken languages; they don’t have true grammars, or large vocabularies, or the ability to express abstract concepts
    • They were “invented”; they didn’t evolve naturally among communities over time
    • They have to be explicitly taught; they cannot be acquired naturally by children through exposure as with spoken language
  • Sign languages are the visual equivalent of spoken languages – for example, American Sign Language is the visual equivalent of English

I’ll also spend some time discussing “baby sign language” (which is of personal import due to last year’s arrival of my very own teacup human).

Sign languages

Sign languages are natural languages whose modality is visual and kinesthetic instead of speech- and sound-based. They exhibit complexity parallel to that of spoken languages, with rich grammars and lexicons. Sign languages developed and are used among communities of deaf people, but can also be used by hearing individuals. These languages are not composed solely of hand movements. A good deal of their prosody, grammar (e.g. syntax, morphology), modification (adjectives and adverbials), and other features are expressed through head movements, facial expressions, and body postures.

American Sign Language (ASL)

American Sign Language (ASL) is the main language of Deaf communities in the U.S. and Canada. Contrary to what many assume, ASL is not grammatically related to English. From Wikipedia:

“On the whole […] sign languages are independent of spoken languages and follow their own paths of development. For example, British Sign Language (BSL) and American Sign Language (ASL) are quite different and mutually unintelligible, even though the hearing people of the United Kingdom and the United States share the same spoken language. The grammars of sign languages do not usually resemble those of spoken languages used in the same geographical area; in fact, in terms of syntax, ASL shares more with spoken Japanese than it does with English.”

ASL emerged in the early 1800s at the American School for the Deaf in Connecticut, from a mix of Old French Sign Language, village sign languages, and home signs. ASL and French Sign Language (LSF – Langue des Signes Française) still have some overlap, but are not mutually intelligible.

One element of ASL that I find particularly neat is its reduplication (repetition of a morpheme or word to serve a particular grammatical function, like plurality)[1]. Reduplication is a common process in many languages, and it performs several important jobs in ASL. It does things like pluralize nouns, convey intensity, create nouns from verbs (e.g. the noun chair is a repeated, slightly altered version of the verb to sit), and represent verbal aspects such as duration (e.g. VERB + for a long time).

Baby sign language

What is “baby sign language”? I haven’t found a very precise definition. The term seems to basically describe signing between (hearing) parents/caregivers and young children, but whether the signs come from a legitimate sign language like ASL, or are invented idiosyncratically by the family using them (and are maybe more iconic[2]), or some combination of the two, varies from source to source.

Anthropologist-psychologist Gwen Dewar, on her blog, says:

“The term is a bit misleading, since it doesn’t refer to a genuine language. A true language has syntax, a grammatical structure. It has native speakers who converse fluently with each other. By contrast, baby sign language […] usually refers to the act of communicating with babies using a modest number of symbolic gestures.”

When Dr. Dewar mentions symbolic gestures, she is describing things like pointing or other hand motions that accompany speech and make communication with preverbal infants a little easier. Most of the baby sign language resources I’ve come across endorse using ASL as a base, however, so it’s not just “symbolic gestures”. At the same time, the ASL signs are often simplified (both by baby sign teachers and the parents learning), and the fuller grammar is not usually taught to/learned by parents or their children.

In the following post, I’m going to delve further into baby sign language – its supposed benefits, tips, timelines, resources, and my personal experience so far. We’ll look at proponents’ claims versus the scientific research. (Spoiler: Your offspring won’t be the next Einstein just because you taught them how to sign ‘more’ and ‘milk’.)


*Photo attribution: “Learn sign language at the playground”

[1] More on this process in “I heart hangry bagel droids (or: How new words form)” – see #9.

[2] I’ll discuss iconicity in the next post.

Back from hiatus

Why, hello there! It’s been ages since I’ve posted, but I’ve been pretty busy with a tiny new experiment:


Ryden was born in October (the photo was taken at not-quite-two-months) and is now emphatically ingesting solids, crawling (but only backwards), and beginning to babble.

Now that my life has gone from hallucinatorily topsy-turvy to relatively stable (in a pandemic – yes, that’s how childbirth and newborn-land will relativize things), I plan on posting again more regularly. Coming up, stuff on:

  • frame semantics and FrameNet
  • “parentese” (apropos, yes?)
  • another linguist career interview
  • “crashblossoms”



Koko and animal “language”

Can animals have language the way humans have language? From recent news headlines about a famous ape and her passing, one might conclude: yes. Titles such as “Koko: Gorilla who mastered sign language dies in California” and “Koko, the Gorilla Who Knew Sign Language, Dies at 46” imply that non-human primates, at least, can learn and use language as humans do. So once again I’d like to call the media out on their frustrating inaccuracy.[1]

From the BBC (first article linked above):

“Koko the gorilla, who is said to have been able to communicate by using more than 1,000 hand signs, has died in California at the age of 46. Instructors taught her a version of American Sign Language and say she used it to convey thoughts and feelings. […] The gorilla […] could understand 2,000 words of spoken English.”

From NBC (older article linked to second one above):

“In 2001, Williams visited the Gorilla Foundation in Northern California, where he met Koko, a gorilla who is fluent in American sign language”

By choosing words like master and know and fluent, journalists are misinforming readers (whether this is intentional or out of ignorance, I’m not sure). There are many differences between how Koko understood and used language and how humans understand and use it. Two obvious areas jump to mind: (1) vocabulary size; and (2) ease of learning. Regarding point one – adult native English speakers know between 270% – 500% more words than Koko[2]. A 2016 study found that 20-year-olds were able to identify an average of 42,000 lemmas (dictionary headwords, e.g. run for run, runs, ran, and running). The lowest 5% of the population in the study recognized 27,100 lemmas, and the highest 5% understood 51,700.[3] While I couldn’t find numbers for American Sign Language (ASL) speakers, I assume they would not be too far from the numbers for speakers of English. (Most ASL speakers are bilingual anyway, since they have learned English to read and interact with non-signers.)

As for point two, the ease of learning – Koko had to be explicitly instructed over many years. Human children acquire a relatively complete grammar within about 5-8 years of being born, and they do this even in the absence of active teaching.

More generally, major properties of human language which distinguish it from animal communication are:

  1. Arbitrariness – the relationship between sounds/signs and their meanings is random.
    • Ex.: There’s no reason for why the sound sequence cat has to mean those furry purring domesticated felines.
  2. Productivity/Creativity – people can understand and create an unlimited number of new utterances.
    • Ex. 1: Novel sentences. I bet you’ve never heard the following, although you can easily understand its meaning.
      • Her pet squid squirted aquamarine ink all over the plaid sofa.
    • Ex. 2: Endless modifiers (adjectives, adverbs, etc.).
      • I thought he was really, really, really, really, really, very, super, exceedingly funny.
    • Ex. 3: Subordinate clauses (the below is one type, called a relative clause).
      • This is the dog that worried the cat that killed the rat that ate the malt that lay in the house that Jack built.
  3. Discreteness – human languages are composed of distinct units that combine according to grammatical rules to create meaning.
    • Ex.: Cat is made up of the phonemes /k/ + /æ/ + /t/; cats is made up of the morphemes cat + -s (pluralizes nouns); and on and on into larger and larger units.
  4. Displacement – we have the capacity to talk or sign about things unrelated to “the here and now” (the present space and time).
    • Ex. 1: When he was little he loved turtles.
    • Ex. 2: If I could do anything, I’d become an astronaut and travel to Mars.

Of course, animal communication has been shown to exhibit one or two of the above properties in specific contexts; you may have heard about such research on bird song, bee dances, and the communicative systems of elephants, bats, dolphins, squids, and apes. But at this point we don’t have evidence to suggest that any non-human form of communication displays all of these aspects simultaneously, or to the extent that human language does. That’s not to say that informational exchanges between other species aren’t complex. And this post is not meant to detract from Koko’s life or death. She and her trainers taught us invaluable things about the depth of gorilla intelligence and emotionality. Certainly, as we learn more about how various species communicate, we may need to update our definition of “language”. We’re just not there yet.


[1] The widely-read Language Log also posted on this topic, taking a similar stance: The (Non-) Evolution of language
[2] I won’t get into how “word” is defined, since that by itself would be a very long post.