Typical Child development 1

Initial Questions to Consider

• How does the auditory system develop in utero?

• What are the key milestones for communication development in children aged 0-5 years?

• How can we identify early signs of atypical development in children?

• What is the role of the audiologist in assessing and managing children with communication delays?

• When should we refer a child for further assessment or intervention?

Development of the Ear In Utero

• Early development of inner ear involves sensory placodes (thickenings of ectoderm) forming specialized sensory systems (auditory, visual, nervous).

• Otic placode develops at 4 weeks in utero, before pregnancy is typically recognized.

• Ectoderm thickens and folds in on itself (invaginates), creating the otic pit, which differentiates into specialized inner ear structures (cochlea, ossicles, tympanic membrane, semicircular canals).

• Inner ear development is separate from middle and outer ear development.

• Inner ear labyrinth (cochlea and vestibular structure) continues to grow, relatively complete by week 23.

• External parts of the ear start to form around 7-8 weeks.

Vestibular System Development

• Components of the vestibular system (semicircular canals, utricle, saccule) and sensory organs (macula and crista ampullaris) develop early.

• Auditory nerve and middle ear space also develop rapidly.

Key Milestones for Ear Development

• Week 12: Inner ear is fully formed.

• Week 24: Inner ear is functional; fetus may respond to sounds (mother's voice, heartbeat).

• First and second trimester: Middle ear forms from two pharyngeal arches, forming ossicles and muscles (stapes and stapedius).

  • Implications: Infection or ototoxic medication during pregnancy can have significant consequences on fetal hearing and vestibular development.

Independence of Ear Development

• Inner ear and middle/outer ears develop separately; damage can occur independently in these regions.

Early Childhood Development (0-12 Months)

• Newborns: Limited head control, explore hands, track with eyes; reflexive response to sounds (startle, quiet to mother's voice).

• 3 Months: Better head control, notice hands, grasp objects, interested in faces and high contrast visuals; increased head and neck control/stability.

• 3-6 Months: Turn/localize to sounds, random vocalizations, intentional crying, familiar voices provide comfort.

• 6 Months: More mobile (sit with support, roll), better hand-eye coordination, localize sounds, responsive visually; sitting unsupported, use hands to manipulate objects.

• 9-12 Months: Observe and respond visually, localize sounds, create basic sound combinations (mama, dada); simple understanding of instructions, starting to crawl/cruise, understand simple instructions, use gestures.

Communication At 12 Months

• Crawling or cruising (holding onto furniture while standing)

• Understanding Simple Instructions.

• Using gesture to communicate.

• First word may emerge (not fully developed).

• Separation anxiety is common.

• Performing VRA (visually reinforced audiometry).

Early Childhood Development (1-5 Years)

• 1-2 Years:

  • 15 Months: Walking independently, fine motor skills develop, use familiar words,

  • 15-18 Months: Understanding solidifies, point to people/items.

  • 18 Months: Refined gesture use, increased word count, enjoy music, imitate activities.

  • Motor development (stacking/sorting) apparent.

• 2-3 Years:

  • Mobile (running, stairs), 50 words, two-word sentences asking questions, jargon, echolalia, good instruction following.

  • Play well, wary of strangers, prone to tantrums.

• 3-5 Years:

  • Progression of existing skills, gross and fine motor skills, drawing, building.

  • Large vocabulary, understood by strangers.

  • 4-5 Years: Grammatically correct speech, kindergarten, engage with children, confident with strangers, strong-willed.

• 5 Years:

  • Mini-adult, active, playful, good communication and articulation.

  • Good behavior, sense of identity and awareness of others' emotions.

Reasons for Referral to Audiologists:

• Neonates (0-3 months):

  • Referral from newborn hearing screening, risk factors (in utero, perinatal), genetic factors, lack of response to sound

• Infants (3-18 months):

  • Risk factors, ototoxic medication, childhood illnesses, ear infections, communication development concerns.

• 18 months - 4 years:

  • Ear infections, childhood illnesses, communication development concerns.

• Older children:

  • Child complaints of hearing, parental observation, learning difficulties.

Developmental Milestones Important for Audiologists:

• Required for appropriate test selection and referral decisions.

• Example Framework (Birth to 4 months):

  • Audiology-relevant observations: Startle reflex

  • Common reasons for referral: Not responding to sounds or making sounds.

Pediatric Audiology Tests

• Birth to 6 months:

  • Infant diagnostic testing during sleep (objective tests): ABR, OAEs, Tympanometry; to obtain objective information about hearing and middle ear status.

• 8 months to 2.5 years:

  • Visual Reinforcement Audiometry (VRA): Child behaviorally responds to a tone and is reinforced visually, child turns when they hear a sound and there's something that pops up.

• 2.5 years onwards:

  • Play Audiometry: Requires behavioral response (e.g., putting a toy in a bucket) with fine motor control and instruction understanding required.

• 7 years onwards:

  • Pure Tone Audiometry: Pressing a button when hearing a sound.

• Behavioral Observation Audiometry (BOA):

  • Estimates hearing prior to behavioral response ability (3-7 months).

  • Older child age leads to increased requirements on development and behavior.

  • Various ages with test examples discussed.

  • Infant Diagnostic Testing: Stickers recording electrophysiological response with tiny little earmuffs for the audiological assessment.

  • Visual Reinforcement Audiometry (VRA): The child is turning to a puppet or a screen where they're turning to that response, turning to stimulus.

  • Play Audiometry: Engaging with a game for audiological assessment.

Pre-Verbal Communication Overview

• Pre-verbal communication: Interaction before first word (birth to ~12 months).

• Language: Signs/symbols conveying meaning (verbal/non-verbal).

• Speech: Articulation/mechanics of speaking.

• Pyramid:

  • Base: Pre-verbal communication and early interaction.

  • Middle: Language (receptive/expressive).

  • Top: Speech (production/fluency).

• Social interaction and play skills in addition to attention and listening skills are a key component to communication development.

Pre-verbal Skills as Building Blocks

• Pre-verbal skills significantly impact spoken communication ability.

• Listening/interaction skills enhance communication development.

• Ultimately leads to language development and sounds production.

• Requires ability to hear what's being said (good hearing).

• Requires that there is memory (cognitive development).

• Requires the ability to listen appropriately in a way that shows the child requires the ability to learn/listen.

Preverbal Communication Elements

• Non-verbal Skills eye contact, turn taking, pointing, joint attention.

• Receptive Language is generally bigger.

• First words roughly around 12 months.

• Caregiver interaction scaffolding infants communication.

• Caregiver Speech Modifications Modifications to the way in which interacr/speak with the chld.

• Speech and Behaviour Modification from Caregiver interaction.

• Visual Information and Eye Contact to gain attention.

• Signaling Interest through Visuals and Shared visual attention between infant and caregiver.

Vocal Behaviour and the Different Stages of Preverbal Development Across Time.

• Newborn: Only sounds are crying of some form.

• 3 months. Make vowel liked sounds called cooing and going.

• 6 months babbling where the infant starts to play with sounds producing.

• 8-10 months. Babbles become more diverse.

• 12 months First word emerges and the infant is then able to demonstrate their first word.

• Demonstration of how the Infant gains Communication Development across time.

Caregiver Crucial Role

• Scaffolding interaction; Modifying behaviors.

• Not easy for everyone; Learned skill.

• The Caregiver is there to assist in Communication Development by utilizing Speech and behaviors when engaging and talking to the infant.

Language Development (Receptive and Expressive)

• Language: System of signs/symbols unique to culture.

• More than one language and dialects present on the planet.

Three Components of Language:

• Structure (syntax, morphology, phonology).

• Content (vocabulary/lexicon).

• Use (pragmatics).