Phonetics of Signed Languages: Production and Perception

Phonetics of Signed Languages

Producing and Perceiving Signs

  • This lecture discusses the phonetics of signed languages, focusing on how signs are produced and perceived.

Acknowledgement

  • Images are from Crasborn, Onno & Els van der Kooij. 2016. “Chapter 10: Phonetics”. In The Linguistics of Sign Languages: An Introduction, ed. by Anne Baker, Beppe van den Boegaerde, Roland Pfau & Trude Schermer, pp. 229–249. John Benjamins.
  • The book is accessible through Library Online Course Reserves on the course website in Canvas.

The Speech and Sign Chain

  • Speech Chain
    • Speech Organs --> Sound Waves --> Ears
  • Sign Chain
    • Hands, Upper Body, Head --> Light Waves --> Eyes

Components of a Sign

  • Main parameters in American Sign Language (ASL) include:
    1. Handshape
    2. Palm Orientation
    3. Location (on upper body/head)
    4. Type of Movement (or lack thereof)
    5. Facial Expressions (“non-manual signals”)

Handshape

  • Handshape is a key component of a sign.

Orientation

  • Palm orientation is a key component of a sign.

Location

  • Location is a key component of a sign.
  • Example: SUMMER is signed in a specific location.

Location Example

  • Location is a key component of a sign.
    • Example: DRY is signed in a specific location.

Movement

  • Movement is a key component of a sign.
  • Example: CHAIR vs. SIT demonstrate differences through movement.

Movement Example

  • Movement is a key component of a sign.
    • Example: TRAIN is signed with a specific movement.

Facial Expressions

  • Facial expressions are a key component of a sign.

Facial Expressions Example

  • Facial expressions are a key component of a sign.

Components of a Sign (Revisited)

  • Main parameters in American Sign Language (ASL) include:
    1. Handshape
    2. Palm Orientation
    3. Location (on upper body/head)
    4. Type of Movement (or lack thereof)
    5. Facial Expressions (“non-manual signals”)

Distal vs. Proximal Movement

  • Distal movement is generally easier than proximal movement.
    • Requires less energy.
  • However, this is not the case for young children.
    • Fine motor control is still underdeveloped.

Finger Extension

  • Index and little fingers each have their own dedicated extensor muscle.
  • Middle and ring fingers do not; it is much harder to extend them alone.

One-Handed vs. Two-Handed Signs

  • Vocal Tract: 1
  • Hands: 2
  • One-handed signs are typically produced with the signer’s dominant hand.
  • In two-handed signs, certain patterns of coordination between the two hands’ movement are preferred (easier for the brain!).
    • Synchronous (a)
    • Alternating (b)
    • Only one hand moves; the other is stationary (c)

Sign Language Perception

  • Finer-grained / smaller contrasts can be made near the center of the visual field.
    • These are still robustly perceived as distinct from each other.
    • e.g., [mouth] vs. [cheek] vs. [chin] as distinct locations
      • All very close to each other.

Sign Language Perception Example

  • [mouth] vs. [chin] vs. [cheek] used as distinct locations in Sign Language Netherlands (SLN).
  • cf. periphery of visual field: just [shoulders] vs. [chest] vs. [belly]

Similarities (and Differences)

  • In both spoken and signed languages:
    • There are physical constraints on the parts of the body that are used for production and perception.
    • These constraints seem to shape the types of gestures/sounds/signals etc. that tend to get utilized in languages, and their implementation.
  • However, the nature of those constraints may differ between the two modalities.
  • We can study these physical details of production and perception in signed languages no less than in spoken languages!