Audiology Flashcards
(128 cards)
neuroplasticity
the ability of a baby’s brain to change with learning
synaptic pruning
- unused or weak connections are eliminated
- strong connections are strengthened
when do babies with typical hearing start hearing
20 weeks
ears function
- transmit and transduce sound to the brain
- maintain balance
brain
true hearing organ
optimal time for auditory neural connections to form
first 3 years
babies born with hearing loss
- missed 20 weeks of typical development of the auditory brain before birth pathways before birth
- missed auditory neural development after birth and that would have happened with hearing aids
0-4 months (hearing milestones)
- startle to loud sounds
- sensitive to a wide range of sounds
- quiet to familiar voice
4-6 months (hearing milestones)
- localize sound
- angry v. friendly voices
- like sound-making toys
6-12 months (hearing milestones)
- turn to mother’s voice
- repeat sounds
- respond to their name, “no-no”, and “bye-bye”
12-18 months (hearing milestones)
- imitate spoken words
- word approximation (dog = ruff ruff)
- jabber in response to human voice
- understand ~50 words
18-24 months (hearing milestones)
- understand simple sentences
- echo prominent/last words spoken
- use 10-15 words by 24 months
24-30 months (hearing milestones)
- understand and answer yes/no questions, simple “wh-“ questions
- listen to simple stories
- follow simple directions
30-36 months
- understand nearly all sentence types
- communicate effectively with strangers
- understood by others
parts of the ear
- outer ear
- middle ear
- inner ear
auditory path
sound waves travel from the outer ear → auditory canal (causes ear drum or tympanic membrane to vibrate which causes ossicles to move) → oval window → fluid in cochlea and inner ear (vibrations into electrical impulses) → brain
outer ear features
- pinna
- auditory canal/meatus
- tympanic membrane (eardrum)
pinna
- cartilage and soft tissue
- only visible part of the ear (auricle)
- localization
pinna function
- direct sound into the ear (without it, sound would be lost making it harder to hear)
- helps overcome pressure difference (air pressure higher in the ear)
- transition into the auditory canal smoother
auditory canal
- transmit sound from the pinna to the eardrum
- natural hearing aid (amplifies low sound, compensate for human voice weakness)
tympanic membrane
- sensitive membrane at the end of the auditory canal
- pressure from sound waves makes the eardrums vibrate
- marks beginning of middle ear
- slightly curved to make it difficult to insets to get in
- earwax
earwax function
keeps dust, dirt, and insects out
middle ear features
- ossicles (malleus, incus, and stapes)
- oval window
- round window
- eustachian tube
middle ear function
acoustic transformer (amplify sound waves before moving them to the inner ear)