Au. Lecture 2: Assessment of Special Population

Paediatricother impairments- sever physical handicaps-cognitive impairments-aphasicfunction hearing loss

1. greater reliance on physiological tests2. adapt test situation/technique to better match the capabilities of the special patient

1. Hearing can't be measured directly- physiological measures are limited- no unique observable behaviour attached to audition- must draw inferences from behaviour
2. Assessment focus:- does the individual have functional hearing skills, i.e. he/she able to use audition to perform essential, age-appropriate tasks via audition

1. use a response that is within the behavioural repertoire of the patient- easy for patient to perform, easy for us to observe2. Structure a task that allows us to establish that the behaviour is emitted when a stimulus is heard3. Several general methods used- but challenge is often unique to the individual-input from related professional is often critical
bottom line: STIMULUS RESPONSE appropriate

Same basic goals- identify HL-describe type, severity, configuration-understand how it impacts the individual-identify rehabilitative needs

1. How goals are achieved- more challenging-physical, cognitive, linguistic limitations/immaturities-greater use on physiological tests-modified approaches to behavioural testing
2. Greater urgency- for ID and intervention - earlier is better
3. Ongoing, evolving process- intervention and assessment occur in parallel- don't wait until full picture is available
4. Greater inter-professional coordination- HL impacts development in varied ways (team approach is best)

1. Developmental level2. Age3. Neurocognitive maturation4. Linguistic level / abilities- understand instructions-perceptual response to test stimuli-ability to provide a verbal response5. Normally developing child- can do adult-like procedures by 6 years of age; younger (4-5 years) if motivated and/or bright

BOA - observationVRA & TROCA - operant conditionPlay audiometry
Speech audiometry

- cross check- help gauge severity of hearing loss- focus on functional abilities, can be useful in and assessing effectiveness of intervention

Behavioural Observation Audiometry1. developed to assess hearing from 0-2 years because physiological measures were available (now used to assessed 0-6 months)2. Involves looking at reflexive or attentive responses to to relatively intense signals3. no reinforcement is provided4. performed in sound field- not ear specific; better ear if ears differ

Advantages- time efficient- low techcan provide useful cross-check infocan be first indicator to suggest hearing loss (if other methods not available)
Disadvantages:- require experienced tester to derive most reliable, valid assessment- responses being measures extinguish quickly (habituate) since reinforcement is not used- only measure the loud sounds; not measuring detection- info ear specific- info may not be frequency specific- threshold responses are suprathresholds

Noise makers- some sets commercially available- freq characteristics are available- intensity level at varied distances can be estimated
Warble tone or narrow-band noise (via audiometer
Speech signals - child's name, hello, byebye
Best signals have sudden rapid onsets!

Vary with Age
Reflexive - startle to loud sound; usually done last (i.e. if starting to tire)- arm or leg jerks- slow limb movement-change in sucking behaviour-eye blinks-facial twitches
Attentive- quieting response (ie. decreases in ongoing activity)- or increase in activity-breath-holding or change in breathing rate-onset / pause in vocalization-start or stop crying-eye widening-searching or localizing sound source-smiling or change in facial expression-brow furrowing-shriek of surprise

Auditory behaviour index
- Shows what behaviours to expect at different ages for specific signals/intensities
- Developmentally delayed children will proceed through the same sequence as the normal child but with a delay - auditory responses are more similar across children of the same mental age rather than chronological age

- Beginning around 6 months through 2-3 years
- VRA (visual reinforcement audiometry)
TROCA (tangible reinforcement operant conditioning audiometry)
Measure "minimal" response levels" (not equivalent to thresholds in adult responses) - minimal response levels improve older time as the child gets older and becomes adult.... not the auditory system it's the development of the ability of listen