Auditory Steady State Responses (ASSRs):
Pros and Cons for Clinical Use
 Advantages (Pros)
 Reasonably frequency specific stimuli
 Can be used for electrophysiological assessment of severe to
profound degree of hearing loss in infants and young children
 FDA-approved clinical devices available
 Automated analysis
 Potential disadvantages (Cons)
 Requires very quiet state of arousal
 Sedation or anesthesia is often necessary
 Limited anatomic site specificity
 Analysis difficult with bone conduction stimulation
Estimation of Frequency-Specific Auditory Thresholds
for Infants with in Severe-to-Profound Hearing Loss:
An Important Application of ASSR
ASSR Permits Early, Objective, and Confident
Diagnosis of Candidates for Cochlear Implants
Auditory Steady State Response (ASSR):
New Investigations and New Applications
(> 600 Peer Reviewed Publications)
• Venail et al (2014). Refining the audiological assessment
in children using narrow-band CE-chirp-evoked steady
state responses. Int J Audiol, 18, 1-8 (France)
• Rampp et al (2014). Viability of intraoperative auditory
steady state responses during intracranial surgery. J Clin
Neurophysiol, 31, 344-351 (Germany)
• Hatzopoulos et al (2012). Hearing threshold prediction
with ASSRs and estimation of correction functions to
compensate for differences with behavioral data in adult
subjects: Part 1: Audera and CHARTR EP devices. Med Sci
Monit, 18, 47-53
• Drouillard et al (2014). Pseudohypacusis in children:
Circumstances and diagnostic strategy. Int Pedi ORL, Epub
Update on Auditory
Electrophysiology
• Introduction to auditory electrophysiology …
85-years of research and clinical application
• Electrocochleography (ECochG) … Much more
than just the diagnosis of Meniere’s Disease
• ABR … Over 4000 peer-reviewed publications in
the past decade alone
• ASSR … Filling an important niche in children
and adults
• Cortical auditory evoked responses … Now
Cortical Auditory Evoked Responses:
Objective Measures of Central Auditory System Function
P300
ALR
AMLR
ABR
ECochG
Dan Geisler, Ph.D.
Discoverer of Auditory Middle Latency Response
(AMLR) in 1958
Geisler, C. D., Frishkopf, L. S., & Rosenblith,
W. A. (1958). Extracranial responses to
acoustic clicks in man. Science, 128, 12101211.
Cody, D. T. R., Jacobson, J. L., Walker, J. C., &
Bickford, R. G. (1964). Averaged evoked
myogenic and cortical potentials to sound in
man. Annals of Otology, Rhinology, and
Laryngology, 73, 763-777.
Auditory Middle Latency Response (AMLR):
Analysis
Pa (22 - 30 ms)
Amplitude (mV)
Pb
1 mV
Na
Nb
PAM
PAM = Post-auricular muscle
100 ms
Origins of the Auditory Middle Latency Response (AMLR)
(Photograph adapted from F.E. Musiek)
Primary
Auditory
Cortex
Thalamus
(Medial
Geniculate
Body)
Primary
Auditory
Cortex
Thalamus
(Medial
Geniculate
Body)
Abnormal Patterns of AMLR with Right Hemisphere Lesion
Electrode Effect
Right Hemisphere
C6
Left Hemisphere
C5
Pa
RE
V
V
Pb
RE
Na
Na
LE
LE
Right Ear
Left Ear
Sensitivity and Specificity of the AMLR in
the Detection of Auditory CNS Dysfunction
• Musiek F, Charette L, Kelly T, Lee WW, Musiek R. Hit and false-positive rates
for middle latency response in patients with central nervous system
involvement. JAAA 10: 1999.
– 26 adult control subjects and 26 patients with medically confirmed CANS
lesions (mostly CVAs and lobectomies)
– Two groups matched for hearing status and age
– AMLR measured with hemispheric electrode array (C3 and C4)
– Latency measured for Na and Pa
– Amplitude measured for Na-Pa
– ROC curves generated by plotting hit rate by the false-positive rate for
different criteria, e.g., absolute latency and amplitude, and differences
in these parameters for ipsi versus contra AMLRs
Abnormal Patterns for Auditory Middle Latency Response (AMLR)
in Patients with Confirmed Temporal Lobe Lesions
(Musiek et al, 2007)
AMLR Component (Amplitude in mV)
Na-Pa
Na
Pa
Hemisphere
Side of Lesion
Mean
(SD)
0.55
(0.20)
0.20
(0.14)
Mean
SD
0.86
(0.21)
0.28
(0. 15)
0.35
(0.24)
Intact Side
0.63
(0.27)
Ear and Electrode Effects in Pediatric
Auditory Middle Latency Response (AMLR) Recordings
•
Weihling J, Schochat E & Musiek F. (2013) Ear and electrode effects reduce within-group
variabiliy in middle latency response amplitude measures. International Journal of
Audiology, 51, 405-412
– 155 children
• Normal peripheral function
• Normal central auditory function
• No history of psychological, neurological, or learning disorders
– Na-Pa amplitude differences were measured for
• AMLR C3 – C4 hemispheric electrode recording sites
• Left ear – right ear stimulation
– Conclusions
• Within group variability was significant smaller for relative differences when
compared to absolute measures
• Electrode effects showed significantly less variability than ear effects
• Authors reports normative data
Normal Expectations for Electrode Effects in Pediatric
Auditory Middle Latency Response (AMLR) Recordings
(Weihling, Schochat & Musiek, 2013)
Normal Expectations for Ear Effects in Pediatric
Auditory Middle Latency Response (AMLR) Recordings
(Weihling, Schochat & Musiek, 2013)
Documenting Benefits of Auditory Training with
Auditory Middle Latency Response (AMLR) Responses
• Schochat E, Musiek FE, Alonso R & Ogata J (2010).
Effect of auditory training on the middle latency
response in children with (central) auditory
disorder. Brazilian Journal of Medical and
Biological Research, 43, 777-785
– Subjects
• 30 children (age 8 – 14 years) with APD
• 22 children without APD
– Diagnosis of APD
• Pediatric speech intelligibility (PSI) test
Documenting Benefits of Auditory Training with
Auditory Middle Latency Response (AMLR) Responses (2)
• Schochat E, Musiek FE, Alonso R & Ogata J
(2010). Effect of auditory training on the middle
latency response in children with (central)
auditory disorder. Brazilian Journal of Medical
and Biological Resarch, 43, 777-785
– Auditory training protocol
•
•
•
•
Frequency discrimination training
Intensity discrimination training
Temporal (duration) discrimination training
Dichotic Inter-aural Intensity Difference (DIID
Documenting Benefits of Auditory Training with
Auditory Middle Latency Response (AMLR) Responses (3)
Schochat E, Musiek FE, Alonso R & Ogata J
(2010). Effect of auditory training on the middle
latency response in children with (central)
auditory disorder. Brazilian Journal of Medical
and Biological Resarch, 43, 777-785
Pre-training click-evoked AMLR C3-A1 Na-Pa
amplitudes were smaller in the APD group
0.84 uV for APD group
1.18 uV for control group
8 week period of auditory training for APD group
Documenting Benefits of Auditory Training with
Auditory Middle Latency Response (AMLR) Responses
(Schochat E, Musiek FE, Alonso R & Ogata J, 2010)
Hallowell Davis, Ph.D.
“Father of Auditory Evoked Responses”
Co-Discoverer of ALR in 1939 and P300 Response in 1965
Davis, H., Davis, P. A., Loomis, A. L., Harvey, E. N.,
& Hobart, G. (1939). Electrical reactions of the
human brain to auditory stimulation during sleep.
Journal of Neurophysiology, 2, 500-514
Auditory Late Response (Cortical)
Amplitude (mV)
5mV
P2 (180 – 200 ms)
P1 (50 ms)
N1 (90 - 150 ms)
N2 (200 - 400 ms)
600 ms
Stimulus
P300 Response:
Classic Oddball Paradigm
P2
Amplitude (mV)
Frequent
Unattended
e.g., 1000 Hz or /da/
P3 (300)*
P2
Infrequent (rare)
Attended
e.g., 2000 Hz or /ga/
* P3b
500 ms
Auditory Late
Response: Generators
P300
N2
P2
N1
Clinical Applications of Auditory Late Response
(> 7000 Peer Reviewed Publications for “CAEP”)
Objective documentation of cortical auditory dysfunction
in diverse clinical populations, e.g.,
 Auditory processing, language, and reading
disorders
 Traumatic brain injury
 Neurological and neuropsychiatric disorders
Objective assessment of hearing thresholds in
suspected false or exaggerated hearing loss, especially
adults seeking compensation
Documentation of benefits of intervention in infants and
young children, e.g.,
 Amplification
 Cochlear implants
Clinical Applications of Auditory Late Response
(Anu Sharma, PhD, University of Colorado)
 Cardon G, Campbell J and Sharma A (2012). Plasticity in the developing auditory cortex:
Evidence from children with sensorineural hearing loss and Auditory Neuropathy
Spectrum Disorder. Journal of the America Academy of Audiology
 Sharma, A, Cardon G, Henion K and Roland P (2011). Cortical maturation and behavioral
outcomes in children with auditory neuropathy spectrum disorder. International Journal of
Audiology,50, 98-106
 Sharma, A, Nash A, and Dorman A (2009) Cortical development, plasticity and
reorganization in children with cochlear implants. Journal Communication Disorders, 42,
272
 Gilley PM, Sharma A, Dorman M and Martin K. (2006) Abnormalities in central auditory
maturation in children with language based learning disabilities. Clinical Neurophysiology,
117, 1949
Clinical Applications of Auditory Late Response:
Hearing Aid versus Cochlear Implant Performance
(Anu Sharma, PhD, University of Colorado)
Clinical Applications of Auditory Late Response:
Documenting Cortical Maturation
(Anu Sharma, PhD, University of Colorado)
Clinical Applications of Auditory Late Response:
Documenting Hearing Aid Performance
(Anu Sharma, PhD, University of Colorado)
Clinical Applications of Auditory Late Response:
Hearing Aid versus Cochlear Implant Performance
(Anu Sharma, PhD, University of Colorado)
Clinical Applications of Auditory Late Response:
Cochlear Implant Performance
(Anu Sharma, PhD, University of Colorado)
Clinical Assessment of APD with the ALR:
How Can We Make it Happen?
 Accepted evidence-based test protocol
 Clinical instrumentation with new features (ALR options), e.g.,
 Multiple channels for hemisphere and eye blink electrodes
 Speech stimuli available within ALR protocols
 APD protocols for measurement of ALR, e.g.,
 Speech-in-noise
 Dichotic stimuli
 Temporal processing (gap detection)
 Statistical analysis of ALR parameters, e.g.,
 Latency
 Amplitude and amplitude under the curve
 Normative data (collected with clinical instrumentation)
 Maturational data on ALR
 Latency and amplitude data for various stimuli
Auditory Event-Related Potentials to Words:
Implications for Audiologists
James Jerger, Jeffrey Martin & Katharine Fitzharris
Plural Publishing, 2014
Auditory Event-Related Potentials to Words:
Implications for Audiologists
James Jerger, Jeffrey Martin & Katharine Fitzharris
Plural Publishing, in press
Listening Task = Repeating the word that is heard
Thank You!
Questions?
Digital Version in 2015
Pearson, 2014