Dissertation

Summary

Signers and linguists have noticed for a long time that many signs look like what they mean. In linguistics, a sign that resembles its meaning is called an iconic sign. For example, in a sign in American Sign Language (ASL) that means "banana" (click here to see a video from ASL Signbank (Hochgesang et al., 2023), the pointer finger of one hand resembles a banana and the fingers and movement of the other hand resemble a hand peeling a banana. Spoken languages also have iconic words. Onomatopoeia is an example of this: a word like "splash" sounds a lot like the noise that splashing water makes. But many linguists think that iconicity is more common in signed languages than in spoken languages. If that's true, it could be because signed languages are visual, and many of the things we have words for can be described in terms of how they look. 

Historically, the large number of iconic signs made some people think that signed languages weren't real languages but more like miming or charades. They believed that, in order to be a true language, words had to be collections of sounds that have no relationship to  their meaning. Signed languages don't use sounds, but, rather, configurations and movements of the signer's hands and body. Even though these configurations and movements often "mimic" something about the sign's meaning, each signed language has its own set of handshapes, movements, and locations, and patterns of how these sign parts fit together. So even if the sign for "banana" also like a person peeling a banana in another signed language, it still wouldn't look exactly the same as the ASL sign for "banana." In spoken language, we see this with words for animal noises: the words can sound different in different languages but still all be examples of onomatopoeia. Iconic signs are also used consistently within a signing community; signers don't make up a gesture that looks like peeling a banana each time they talk about a banana. They use the same sign they've learned and that others in their language community understand. And finally, iconic words and signs follow the same grammatical patterns as other words in the language, even when that makes them less iconic. For example, in English when I talk about the past, I can say, "They splashed water all over the room." In this sentence, the word "splash" is less iconic, because adding "-ed" makes the word sound less like real water splashing.

Now that we know that signed languages are real languages, and that both signs and spoken language words can have iconicity, we still have a big question:

Do our minds treat iconic signs any differently than non-iconic signs?

If the answer to this question is "yes," one way we might be able to tell is by asking how the same sign can be produced differently in different contexts, and whether a sign's iconicity has anything to do with this. We've already said that even if a sign is iconic, it follows patterns that are specific to that signed language and are used consistently within a community. But the example we talked about above of "splash" and the past tense "splashed" is required for a sentence to be correct in some (but not all!) dialects of English. In everyday language, it's common for words to be said or signed in different ways that aren't required but are more likely in certain circumstances than others. In English, the word "memory", for example, sometimes sounds like "mem-ree" and other times sounds like "mem-or-ee." Factors like how fast you're talking, who you're talking to, or just individual preference could affect which version you use. Both would make sense and sound natural. The same is true in signed languages. An ASL sign that's usually made with the hand touching the forehead, for example, might be signed with the hand near the chin if someone is signing quickly, if another sign in the sentence is lower on the body, or if the person signs a certain dialect where this version of the sign is common. 

The specific question my dissertation tries to answer is:

Are signers less likely to apply optional changes to iconic signs if that change makes the sign less iconic?

To answer this question, I looked at examples of two kinds of changes that can happen to ASL signs. One is a change in the location where the sign is made. For example, in ASL, the sign that means "think" (click here for an example) is usually produced on the forehead. This location is iconic, because we think with our brains and our brains are in our heads. But I might sign "think" at a lower location if I'm signing quickly, and this would make the sign less iconic. Other signs are also produced at the forehead, but this location isn't iconic for all of them. The sign that means "lettuce," for example (click here to see a video), happens on the forehead, but there's nothing about lettuce that makes the forehead iconic in that sign. Are signers less likely to sign "think" at a lower location than they are to sign "lettuce" at a lower location, since "think" would become less iconic but "lettuce" would not? If that's true, that might mean that our brains treat iconic signs and non-iconic signs differently. 

The second kind of change I looked at is when a sign is usually two-handed but gets signed with only one hand.  This is a process that can happen 

For example, the ASL sign that means "chop" (see a video here)