deaf language develpment2
saif29
454_chpt_2_pp1-1.pptxChapter 2: Structural Bases of Human Communication
SPCE 454
McLaughlin
p. 54-61
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Speech mechanism = structures for speech production
Anatomical Structures for Speech p.54
Respiration = process of ventilating the body to inhale fresh air and exhale used air
Lungs
Two sponge-like structures encased in the ribcage
Primary purpose is to serve respiration
Humans have adapted them for communication
Breathing for speech is the same as respiration
The difference is the duration of the cycle
For respiration = same duration for inward and outward breathing
For speech = outward breathing is controlled and extended
The Lungs and Respiration
Larynx “voice box”
Responsible for transforming the airstream into phonation
Vocal Folds
Vibrating elastic-like structure
Close to keep away foreign objects
Closed (adducted) until forced open by subglottal air pressure
Both protect the airway, specifically the trachea and lungs
The Larynx and Phonation
Vocal Tract
Pharynx (throat)
Oral cavity
Nasal cavity
These resonate and modify sound of the basic vocal tone based on shape and size
Oral and Nasal Cavities
Articulators = structures that can be manipulated to make sounds
Lips
Tongue
Jaw
Teeth
Soft palate (velum)
For vowels, the sound passes through an open oral tract, other than the lips which move to accommodate the vowel sound.
Consonant sounds are much more restricted by the articulators
Oral Structures and Articulation
Our ears play a role in communication that is no less important than the mouth
Infants must hear the sounds, words, and phrases of a language if they are eventually to reproduce them
It becomes difficult to communicate if children cannot hear models or feedback
Anatomy and Physiology of Hearing
Auricle/pinna
Most visible feature of the outer ear
Minimally funnels sound into ear
External auditory meatus/ear canal
Slightly curved
One-inch long
Resonates sound that enters the ear
The Outer Ear
Transforms sound waves into mechanical energy
Eardrum/tympanic membrane
Separates the middle and outer ear
Moves in and out in response to the pressure waves of incoming sound
Ossicles – chain of three small bones
Malleus
Incus
Stapes
Eustachian tube
Small duct that connects middle ear to pharynx
Ventilates middle ear cavity, which equalizes air pressure
The Middle Ear
Located in temporal bone of the skull
Semicircular canals
Provide sense of balance and equilibrium as fluid moves in response to body changes
Cochlea
Primary structure concerned with hearing
Coiled structure that resembles a snail
Oval window
Basilar membrane
Organ of Corti
Acoustic nerve (CN VIII) – transmits electrochemical pulses to the brain
The Inner Ear
