Speech Sound Disorders and Hearing Loss Notes

Psycholinguistic vs. Differential Diagnosis Models

  • Psycholinguistic Model (Stackhouse & Wells): Focuses on how the impairment occurs in the speech processing system.
  • Differential Diagnosis Model (Dodd): Focuses on what characteristics of the SSD are present.

Dodd's Differential Diagnosis Model Subtypes

  • Articulation Disorder
  • Childhood Apraxia of Speech
  • Phonological Delay
  • Consistent Phonological Disorder
  • Inconsistent Phonological Disorder

Phonological Delay vs. Phonological Disorder

  • Phonological Delay: Use of developmental phonological processes beyond typical age.
  • Phonological Disorder: Use of non-developmental processes, possibly alongside developmental ones.

Discriminating Articulation vs. Phonological Difficulty

  • Stimulability data: determines if motor function exists to produce sound.
  • Stimulable child: Likely phonological, not articulation, difficulty.

Heterogeneity of SSD

  • Severity
  • Underlying cause
  • Speech error characteristics
  • Involvement of other linguistic aspects
  • Response to treatment

Broad-Based Classification Systems

  • DSM-5: Speech Sound Disorder
    • Diagnostic criteria include persistent difficulty interfering with communication, impacting social/academic/occupational performance, onset in early development, and not attributable to other conditions.
  • International Classification of Function, Disability and Health.

Classifying Children with SSD

  • Aetiological
  • Processing
  • Descriptive linguistic

Speech Disorders Classification System (SDCS)

  • Aetiological factors can co-occur.
  • Lacks guidance on identifying the "most probable" aetiology.
  • Requires further research for clinical applicability.

Speech Processing Model (Stackhouse & Wells, 1997)

  • SSD results from breakdowns in hearing, auditory discrimination, speech output planning, execution, or storage.
  • Tenets:
    1. Typical speech requires a normal processing system.
    2. SSD = breakdown at one/more points.
    3. Targeted breakdown to remediate.

Breakdown in Speech Processing System

  • Incorrect phonetic plan → Articulation disorder
  • Motor planning/programming → CAS
  • Execution weakness/incoordination → Dysarthria
  • Rule-learning issues → Consistent phonological disorder
  • Phoneme selection/sequencing → Inconsistent phonological disorder

Describing the Speech System Information

  • Phonetic repertoire, productive phonological knowledge, phoneme repertoire, severity, phonological pattern, consistency of word production, intelligibility.

Outer Ear

  • Pinna and ear canal collect sound and transmit it to the eardrum.

Middle Ear

  • Includes malleus, incus, and stapes (ossicles).
  • Amplifies sound and transmits it to the cochlea.

Inner Ear

  • Cochlea converts mechanical vibration to electrical signals.
  • Organ of Corti contains hair cells that send electrical impulses to auditory nerves.
  • Semicircular canals are involved in balance.

Hearing Process

  • Hearing takes place at the level of the brain.
  • Brain processes electrical nerve impulses as specific sounds, words, and conversations.

Hearing Loss Classifications

  • Congenital/Acquired, Unilateral/Bilateral, Conductive/Sensorineural/Mixed, Mild to Profound, Permanent/Fluctuating.

Outer Ear Disorders

  • Typically conductive and congenital.
  • Examples: Atresia, Microtia, Stenosis which may result in moderate hearing loss.
  • Surgical reconstruction can manage Atresia and Stenosis.

Middle Ear Disorders

  • Often conductive.
  • Otitis Media (OM): Most common cause of temporary hearing loss in children.
    • Caused by upper respiratory infection. Eustachian tube dysfunction.
    • Can lead to temporary or permanent hearing loss.

Risk Factors for Otitis Media

  • Upper respiratory tract infections
  • Allergy/atrophy
  • Snoring
  • Previous history
  • Second hand smoking
  • Low socio economic status

Other Middle Ear Disorders

  • Malformations of ossicles, Cholesteatoma, Unrepaired cleft palate

Medical Management of Otitis Media

  • Antibiotics, vaccination, grommets (myringotomy).
  • Grommets improve hearing as ossicles can move freely.

Otitis Media in First Nations Children

  • High prevalence among Aboriginal and/or Torres Strait Islander children.
  • Higher severity and impact.

Inner Ear Disorders

  • Usually sensorineural.
  • Malformations in the cochlea, damage to hair cells within the Organ of Corti.
  • Can also affect vestibular system.

Auditory Processing Disorder (APD)

  • Difficulties identifying sound in background noise and localising sound.
  • Impacts learning and attention.

Tinnitus

  • Ringing in ears in absence of external sound.
  • Fault in hearing system, often cochlea.
  • Can be caused by noise exposure, middle ear problems, medications, or Meniere's disease.
  • Impacts sleep, concentration, and functioning.

Noise Induced Hearing Loss

  • Long-term exposure to loud sounds damages hair cells.

Presbycusis

  • Age-related hearing loss affecting all parts of the hearing system.

Other Causes of Hearing Loss

  • Maternal rubella, Cytomegalovirus (CMV), Meningitis, Measles and mumps, Ototoxic drugs, Genetics.

Changing Face of Hearing Loss

  • Technology drives practice; significant advances in outcomes in the last 20 years.
  • Outcomes influenced by newborn hearing screening, modern technology, early intervention, and research.

Newborn Hearing Screening Implications

  • Early identification leads to early management.
  • Early amplification allows development of listening and spoken language.

Modern Hearing Technology

  • Audiological testing equipment.
  • Digital hearing aids, implantable devices maximize sound and reduce background noise.

Binaural Hearing Benefits

  • Localisation, speech in noise, speech clarity, less fatigue, higher vocabulary and language skills.

Early Intervention Implications

  • Children can catch up with typically hearing peers.
  • Accessing critical period for listening development (up to 3.5 years).
  • Early intervention facilitates brain-based habilitation, following a developmental pathway.

Research Guiding Clinical Practice

  • Evidence-based practice, clinical benchmarks, informed parents.

Speech Pathology Management of HL

  • Facilitates use of technology, works with audiology team and family.
  • Children with HL can have trouble with speech perception/production, prosody, and intelligibility.

Early Intervention Types

  • Listening and Spoken Language, Total Communication, Bilingual Bicultural.

Listening and Spoken Language

  • Focus is on development of spoken language through early identification, technology, and intervention.

Total Communication

  • Simultaneous use of manual and oral modes.

Bilingual Bicultural

  • Children part of Deaf community; Auslan is primary language.

Joint Committee on Infant Hearing

  • Recommendations for management of children with HL.

Future Research

  • Large scale studies, comparison groups, common assessment batteries.

Management of HL in Older Children and Adults

  • Auditory Training helps integrate sound signal from cochlear implant.
  • Enhance Listening using Assistive Devices and Classroom Acoustics.

Assistive Listening Devices

  • Personal FM Systems, Soundfield systems.

Classroom Acoustics

  • Noise levels, signal-to-noise ratio (SNR), reverberation time (RT), distance.

Team for HL Management

  • Teacher, teacher aid, Advisory Visiting Teacher, parents, and child.

Implantable Technologies

  • Cochlear implant, Middle Ear Implant, Hybrid implant, Auditory Brainstem Implant.

Organic Speech Sound Disorders

  • Childhood Apraxia of Speech, Dysarthria, Speech sound disorder associated with cleft and craniofacial conditions.

Childhood Apraxia of Speech (CAS)

  • Neurological speech sound disorder with imprecision and inconsistency of speech-related motor movements.
  • Features include inconsistent errors, lengthened coarticulatory transitions, inappropriate prosody.

Comparing CAS to Inconsistent Phonological Disorder

  • Inconsistency is key in both.
  • CAS has prosody issues, and better spontaneous speech than imitation (reverse for Inconsistent Phonological Disorder).

Inconsistent Phonological Disorder

  • Functional speech sound disorder with variable productions of same lexical items.
  • Criteria: >40% words produced differently on 2/3 elicitations.
  • Good oromotor skills, better at imitation than spontaneous production.
  • Core problem = Phonological planning deficit.

Differential Diagnosis Between CAS and Inconsistent Phonological Disorder

  • CAS = issues with prosody
  • CAS better spontaneous speech than imitation, Inconsistent Phonological Disorder better at imitation than spontaneous.

Intervention for Inconsistent Phonological Disorder

  • CORE VOCABULARY THERAPY at the whole word level.
    Need to practice planning and production of whole words.
    Need to improve consistency of word productions.

Dysarthria

  • Articulation disorders caused by impairment of the nervous system.
  • Neuromuscular speech disorders affecting respiration, phonation, resonance, articulation, and prosody.
  • Types include Spastic, Ataxic, Hypokinetic, Hyperkinetic, Flaccid, and Mixed dysarthria.

Cleft Palate Speech

  • Characteristics include hypernasal speech, atypical nasal flow, nasalisation, compensatory characteristics, less complex babbling, reduced phonetic inventory.

Types of Clefts

  • Cleft lip (complete, incomplete, bilateral)
  • Cleft palate (soft palate, hard palate, soft and hard palate, bilateral, submucous, bifid uvula)

Velopharyngeal Function and Dysfunction

  • Velopharyngeal insufficiency, Velopharyngeal incompetency, Velopharyngeal mislearning