Central auditory processing disorders (CAPD): diagnosis and remediation Harvey Dillon With thanks to: Helen Glyde Mridula Sharma Dani Tomlin 1 Jess Whitfield Sharon Cameron

National Acoustic Laboratories NAL 2

National Acoustic Laboratories, Sydney, Australia Presentation Overview Central Auditory Processing Disorder (CAPD) Spatial Processing Disorder (SPD) What is SPD and how does it relate to CAPD? What causes it? How do we remediate it? Testing for CAPD Test batteries and remediation Cognitive ability, listening difficulty and academic success Sound Scouts – a new quick online test 3 ????

What is CAPD?

An Auditory Processing Disorder (APD) is a deficit in the way the neural representations of sounds are processed by the brain “What we do with what we hear.“ (Katz, Stecker & Henderson; 1992)

IC: Form full spatial map, Parallel processing paths join, History dependent MSO: Detect interaural time LSO: Detect interaural level AVCN: Frequency analysis, PVCN: Timing well preserved DCN: Inhibitory circuits, pinna cue detection? Parallel processing Needs to be fed to develop & maintain Auditory System: Central Pathways Lateral lemnisci SC: Visual spatial map Cortex: Complex detection Thalamus: Auditory and visual map integrated, relayed to cortex Sorting, comparing and categorizing Perception VNLL: Fed by contralateral CN OK Something not OK

APD creates difficulty in listening i.e. hearing with intent to extract information difficulty understanding speech in noise or reverberation difficulty hearing on the phone inconsistent or inappropriate responses to requests for information difficulty following rapid speech frequent requests for repetition and/or rephrasing of information difficulty following directions difficulty learning a foreign language or new words problems localizing sound difficulty detecting the subtle changes in prosody that underlie humor and sarcasm difficulty maintaining attention a tendency to be easily distracted poor singing, musical ability, and/or appreciation of music academic difficulties, including reading, spelling and/or learning problems AAA (2010)

Assessing children with CAPD Audiometric test (to rule out hearing loss) History A test battery Sometimes proposed to instead make the assessment symptom-based (e.g. use a questionnaire) – CHAPS, SIFTER, LIFE, CCC2, Fisher’s checklist

Disorders other than APD (e.g. language disorders) can also create difficulty in listening Language disorders Attention deficit disorder Auditory working memory deficit Executive function deficit Autism spectrum disorder Low IQ

Difficulty of relying on symptoms

Child fails to understand an instruction Event Acts (inappropriately) based on what was heard Asks for repetition of instruction Does nothing Misbehaves Response by child Interpretation by observer Daydreams Badly behaved Can’t follow instructions Is not very smart Poor concentration 11 Questionnaires (or other ways to gather symptoms) might be able to confirm there is a problem, but can’t tell us the cause. Diagnosing CAPD by symptoms? Cognition Language Auditory processing

CAPD or AD(H)D? Auditory processing deficit Understanding is difficult Don’t pay attention Attention deficit disorder Don’t pay attention

Relation between APD and Attention Disorder 13 Auditory attention disorder 51 Auditory processing disorder 58 Visual attention disorder No disorder Gyldenkaerne et al. (2015) 101 children with listening difficulties

What do we include in “Auditory Processing”? Rapid spectro- temporal analysis Localisation ability Slow temporal analysis Stream segregation Attention Working memory Executive function

Rapid spectro- temporal analysis Localisation ability Slow temporal analysis Stream segregation Attention Working memory Executive function Auditory Processing Ability Cognitive ability What do we include in “Auditory Processing”?

Causation …….. unknown Auditory processing abilities Language abilities Cognitive abilities Academic abilities Reported listening ability

17 ASHA (2005) “(C)APD is a deficit in neural processing of auditory stimuli that is not due to higher order language, cognitive, or related factors." "When I use a word,' Humpty Dumpty said in rather a scornful tone, 'it means just what I choose it to mean — neither more nor less." "The question is," said Alice, "whether you can make words mean so many different things." Moore, Ferguson et al (2010) “What is currently called APD, for individuals without known neurologic lesions, should be redefined as primarily a cognitive disorder, rather than a sensory disorder.” What is APD?

My comment … 18 It is not productive to define APD as either not involving cognition, or as only involving cognition. Rather, focus on finding out Whether individual children have difficulty listening, Why they have difficulty when listening, and What can be done to change that.

Teachers’ CHAPS scores – children referred to Great Ormond Street Hospital for APD assessment Slightly more difficulty More difficulty Considerably more difficulty Same difficulty

Slightly more difficulty More difficulty Considerably more difficulty Parents’ CHAPS scores – children referred to Great Ormond Street Hospital for APD assessment Same difficulty

CAPD SPD

In review CAPD is an umbrella term for a variety of deficits in auditory processing that cause listening difficulties Symptoms shared with other disorders Some differences of opinion in what should be included under the umbrella

Spatial Processing Disorder : Diagnosis, cause, remediation

Spatial Processing Disorder (deficit in spatial release from masking) Noise Speech 24 CAPD test battery √

National Acoustic Laboratories, Sydney, Australia Spatial Processing Disorder – Unique amongst CAPD because we: Know its major cause Can diagnose it, unrelated to cognitive ability Have extensive normative and reliability data Can remediate it (blinded, randomized trial) Remediation generalizes to real life 25

National Acoustic Laboratories, Sydney, Australia 26 Catalyst The Australian Broadcasting Commission

National Acoustic Laboratories, Sydney, Australia Assessing Spatial Processing Ability 27

National Acoustic Laboratories, Sydney, Australia Listening in Spatialized Noise – Sentences Test (LiSN-S) Test ability to separate target stimuli from distracting stimuli that arrive from other directions. Test design to differentiate this ability from other problems. 28

National Acoustic Laboratories, Sydney, Australia LiSN-S Adaptive speech-in-noise test. Virtual auditory environment under headphones. Target sentences from 0º. Distracter stories at 55 dB SPL from either 0º or ± 90º. Stops when SE < 1.0 dB, or max of 30 sentences. 29

LiSN-S Measurement Screen 30 Two Distracters at 55 dB SPL Level of Target (adaptive) SRT ≡ average SNR

National Acoustic Laboratories, Sydney, Australia Same Direction Different Directions Different Voices Four LiSN-S Conditions Same Voice T D1 D2 TD1 D2 TD1 D2 Low Cue SRT Spatial Advantage Talker Advantage D1 D2 T High Cue SRT Total Advantage 31

National Acoustic Laboratories, Sydney, Australia Anticipated Advantage of Using Difference Scores Four base scores likely affected by: Cognitive abilities (memory, IQ, attention) Language abilities (vocabulary, closure skills, second language) Three difference scores relatively immune to these 32

LiSN-S results profile: spatial processing disorder 33

Explanation Screen

Client Assessment Report

Spatial Advantage (≡ Spatial Release from Masking) Better Australia Nth America

High Cue SRT Better p <

National Acoustic Laboratories, Sydney, Australia LiSN-S Cut-off Scores 38 Cameron et al Better

39 LiSN-S Spatial Advantage Test-Retest Reliability (n=95) Better Paired Difference = 0.3 dB p = r = 0.2 Critical Difference Score = 3.3 dB

CHILDREN WITH SPATIAL PROCESSING DISORDER

National Acoustic Laboratories, Sydney, Australia Children with Spatial Processing Disorder Nine children aged 6 to 11 years experiencing listening difficulties in class relative to peers who had no learning or attention disorder and WISC IQ >90 on all subscales (SusAPD group). Eleven children with confirmed language, memory or attention disorders, and WISC IQ overall score >90 (LD group). Assessed on LISN-S and results compared to 70 age- matched controls. Assessed with a traditional (C)APD test battery

National Acoustic Laboratories, Sydney, Australia Cameron & Dillon (2008) LiSN-S vs. Traditional Battery (LD Group)

National Acoustic Laboratories, Sydney, Australia LiSN-S vs. Traditional Battery – SusAPD Group Cameron & Dillon (2008) LiSN-S vs.Traditional Battery (sus CAPD Group)

National Acoustic Laboratories, Sydney, Australia Link between SPD and Chronic Otitis Media (COM) 44

45 SPD and chronic otitis media (COM) 50% of children (24/49) diagnosed with SPD at NAL reported a history of COM. (Dillon et al., 2012). 30% of children (15/50) previously diagnosed with COM at University of Melbourne were diagnosed with SPD. (Graydon & Rance, ongoing). Spatial processing deficit worse for early onset age and longer duration of COM (n=35; Tomlin & Rance, under review). 6 yo children with history of COM have below average spatial advantage (n=17; z= -1.0) (Kapadia et al, 2012) yo adolescents with history of COM have below average spatial advantage (n=20; z= -0.75) (Kapadia et al, 2014). 10% of a population sample (9/90) of Aboriginal children from remote Australia diagnosed with SPD. (Unpublished data). 7% of a population sample (10/144) of Aboriginal children from regional Australia diagnosed with SPD. (Cameron et al., in review).

National Acoustic Laboratories, Sydney, Australia 46 Interpretation Based on These and Other Studies Chronic otitis media Fluctuating access to binaural cues reduced effectiveness in better-ear glimpsing

National Acoustic Laboratories, Sydney, Australia Remediation of SPD: The LiSN & Learn Auditory Training Software 47

National Acoustic Laboratories, Sydney, Australia LiSN & Learn Deficit-specific remediation for SPD. Trains children to attend to a frontal target stimulus and filter out distracting talkers from left and right. Adapts to 70% performance level. Used in the home or schools/clinics). Provides detailed feedback, analysis and reporting. 48

National Acoustic Laboratories, Sydney, Australia Description of LISN & Learn Five games presented on PC over headphones. Target sentences at 0º azimuth. Competing stories - same voice at ±90º - (55 dB SPL). Weighted up-down adaption of target level. SRT calculated over 40 sentences. 131,220 unique sentences. 50 training sessions (2 games x 5 days p/w x 10 weeks). Reward system. 49

LISN & Learn Game Target at 0˚: Distracters at + and -90˚:

Target: The horse kicked six wet shoes

National Acoustic Laboratories, Sydney, Australia LC SRT p = Talker Advantagep = HC SRTp = Spatial Advantagep = Total Advantagep = LiSN-S Results - Pre- vs. Post-Training Cameron & Dillon (2011) 52

National Acoustic Laboratories, Sydney, Australia LiSN & Learn – Preliminary Study 9 children with SPD (6 to 11 years) LiSN & Learn – 2 games/day, 5 days/week, 12 weeks LiSN & Learn SRT (dB) Better Game Number Cameron & Dillon (2011) Average SRT First vs Last 30 Days p = dB

National Acoustic Laboratories, Sydney, Australia Self-Report Questionnaire - Pre- vs. Post-Training Very Hard Hard OK Easy Very Easy SSQ – Listening in Noise: Pre vs Post - p = * Post vs 3MP - p = SSQ – Listening in Quiet: Pre vs Post - p = Post vs 3MP - p = Cameron & Dillon (2011) 54

National Acoustic Laboratories, Sydney, Australia 55 Blinded Randomized Control Study children (aged 6 yrs 0 mths to 9 yrs, 9 mths) diagnosed with LiSN-S as having SPD: a) 5 x LiSN & Learn (experimental group) b) 5 x Earobics (control group) 2. Questionnaires a) Participant (LIFE) b) Parent (Fishers) c) Teacher (LIFE) 3. LiSN & Learn or Earobics training – 15 minutes daily x 60 sessions 4. Re-evaluate LiSN-S and questionnaires post-training

National Acoustic Laboratories, Sydney, Australia LiSN-S Results – Pre vs. Post Training Earobics (n = 5) Lisn & Learn (n = 5) 56 Cameron, Glyde & Dillon (2012) p = 0.5 to 0.7 p = 0.03 to

National Acoustic Laboratories, Sydney, Australia Questionnaires – Post Training Improvements Teachers Children 57 Parents L&L = 22%; Earobics = 9% L&L = 31%; Earobics = 9% L&L = 16 pts; Earobics = 7 pts; where 0 pts = “no improvement” p = 0.028

National Acoustic Laboratories, Sydney, Australia Disclosure The National Acoustic Laboratories, is an Australian government laboratory NAL licences the LiSN-S test to Phonak, and is paid a royalty on sales. NAL directly sells the LiSN & Learn training package through its web site. 58

In review Spatial processing disorder (SPD) can unambiguously be diagnosed SPD is very often caused by protracted otitis media in infancy SPD can be remediated

Testing for CAPD

A typical test battery Gap detection (GIN, RGDT) Dichotic perception (DDT, SSW, CST) Temporal ordering (FPT, PPT) Binaural processing (MLD, LiSN-S) Degraded speech (Compressed speech, LPFS) [Auditory memory (digits forward and reverse)] CAPD if two tests failed by two standard deviations or more

62 Traditional approach to CAPD testing History Audiometry Is there a problem that CAPD might explain? Exclude CAPD; Refer elsewhere No Test result interpretation & diagnosis Non-specific remediation and management: Classroom placement FM use Instruction style Soundfield amplification Auditory training software Detailed test battery Yes

Further problems with a large test battery Increased demands on child’s attention (The tests are often very boring!!) Relevance of the normative data Statistical implications of presenting multiple tests - inflating Type I error rate. 63

Principles in constructing a test battery Include tests where: poor results are linked to poor listening in real life diagnose conditions for which evidence-based remediation exists 64 NAL position statement on CAPD:

National Acoustic Laboratories, Sydney, Australia Test structure LiSN-S high cue Auditory memory (digits forward and reverse) Dichotic digits LiSN-S Remediate (Memory booster) Remediate (FM …..) Remediate (L&L)

Dichotic Digits and Cognition

Dichotic Digits Test , 9 6, 2 Dichotic Digits Difference Test 4, 9 6, 2 Diotic condition Auditory working memory Attention IQ Dichotic presentation Dichotic ability Auditory working memory Attention IQ

Correlations – DDDT and cognition 68 DichoticDiotic Attention - Prudence Attention - Vigilance Number memory forward Number memory reverse Non-verbal IQ0.26

Dichotic vs diotic perception 69 Dichotic presentation Dichotic ability Auditory working memory Attention IQ Diotic condition Auditory working memory Attention IQ R= 0.69

National Acoustic Laboratories, Sydney, Australia FM useage Hornickel and Krauss (2012; PNAS) 70

Results from a clinical service: prevalence and remediation effectiveness

National Acoustic Laboratories, Sydney, Australia Australian Hearing’s CAPD Service Operating in 42 Australian Hearing centers around Australia since May Diagnosis, assessment and management of specific aspects of CAPD. Recruitment targets children experiencing difficulty hearing in background noise. Tests are chosen which: 1.Have been shown to be associated with difficulties in real life. 2.Are reliable, repeatable and relatively quick to administer. 3.Lead to remediation that is backed by research evidence. 72

National Acoustic Laboratories, Sydney, Australia Age Distribution N=618 73

Passes and Fails Hearing screening LiSN - HC Minimal Sensorineural Mild Conductive Unknown LiSN Memory Age DDT Pass Z < Z ≥ SPD Fail 120 Pass (not SPD) 209 Pass 349 Auditory memory Fail 167 < 7 years 76 ≥ 7 yrs 273 Pass 173 Dichotic deficit Fail 100 Testing discontinued 19% 26% 20% 27%

National CAPD service results: LiSN & Learn effects

LiSN & Learn training: COSI results N = 34

Effect of Memory Booster training 77

COSI scores for Memory Booster training

Questionnaire / history AudiometryMeasured disability Is there a problem that CAPD might explain? Detailed test battery Exclude CAPD; Refer elsewhere No Dealing with problems in understanding speech Master test battery Yes Non-specific remediation and management: Classroom placement FM use Instruction style Soundfield amplification Test result interpretation leading to a disorder-specific diagnosis Disorder-specific remediation LiSN & Learn LiSN-S High Cue LiSN-S Spatial Advantage LiSN-S Talker Advantage LiSN-S Low Cue SPD Undiag- nosed deficit Pitch deficit FPT Verbal FPT Hum SPIN Hi Cont SPIN Lo Cont Closure skill deficits ? Top-down training ? DDDT Dichotic DDDT Diotic Integration Deficit ARIA / DIID

In review Big test batteries have big problems, and do not have an evidence-based path to remediation Evidence of benefit exists for: – Training to overcome spatial processing disorder – Training to improve working memory – Use of FM (wireless remote microphone) systems More specific diagnostic tests and corresponding remediation methods are needed

CAPD test scores, listening in real life, academic performance and cognition

Subjects Clinical Group: (n=105) – Children referred for clinical AP assessment – Aged 7.0 to 12.9 years (Mean Age 8.9 yrs, ± 1.5) Control group: (n=50) – No reported auditory, listening or academic difficulties – Aged 7.0 to 12.2 years (Mean age 9.1 yrs. ± 1.4) Peripheral hearing assessments all normal Dani Tomlin

Measures obtained AP Frequency Pattern Test (%) Dichotic Digits Test (%) Gaps In Noise (msec) Listening in Spatialised Noise Sentences test (LiSN-S) (dB) Masking Level Differences (dB) Cognition Non verbal IQ Auditory Working Memory Sustained Attention (Quotient Scores) Academic Results Reading Fluency –WARP NAPLAN (Numerical scores) Listening Ability Questionnaires: LIFE (child) Fisher (Parent) TEAP (Teacher) (Total item scores) Results need to allow for development & comparison of measures  z scores Source: Dani Tomlin

CAPD scores versus cognitive scores Digit Span Forward Digit Span Reverse Non-verbal IQ Sus Aud Atten DDT_L RDT_R FPT GIN MLD LiSN_LC LiSN_HC LiSN_Spat Adv

DDT avg FPT avg GIN avg LiSN avg Mem avg Atten avg NVIQ Listening ability Reading fluency Path analysis (model; no latent variable)

DDT avg FPT avg GIN avg LiSN avg Mem avg Atten avg NVIQ 66% Listening ability Reading fluency Path analysis (results; no latent variable) P=0.12 Most metrics OK 49% 76% 88% 97% 77%

In review Cognitive problems are often associated with failures on commonly used test batteries

Treatment of APD 88 Treatment (i.e. training to reverse the deficit) should be specified on the basis of a detailed diagnosis of the deficit, but there are very, very few examples of an evidence-based treatment that follows from the detailed diagnosis, that improves performance on the test, and that generalizes to real- life benefit.

Harvey Dillon Carolyn Mee Testing hearing is child’s play John SeymourJesus Cuauhtemoc

Hearing loss in those first fitted with hearing aids at 5 or 6 years of age.

Aim 1: develop a game to test for hearing issues in preschool and school-aged children Sensorineural hearing loss Middle ear disorders Auditory processing disorders Aim 2: differentiate these conditions !

Basis of the test algorithm 1.Test of word recognition threshold in quiet  used to set level of rest of test  comparison with threshold for adult useful itself 2.Test of speech recognition in spatially separated noise 3.Test of tone perception in spatially separated noise

Expected results GroupCalibration testSpeech in noise test Tone in noise test Normal√√√ Conductivex√√ Sensorineuralxxx CAPD√x? ESL, language impairment ?x√

PASS: Speech-in-noise average; tone-in-noise good

Normative data: 4 to 12 years Speech in noise Z scores

Deriving results Normal hearing children Obtain scores Regress against age Express scores as z- scores Combine z- scores for calibration, speech and tone Compare z- scores for calibration, speech and tone Overall pass, uncertain, or fail Probable cause of fail Test unknown child

Overall results GroupPassInconclusiveFailIncompleteTotal Norm hear Conductive Sensori Mixed00606 SIM_SPD01304 ESL606012

Correctness of single diagnosis SensoriCondCAPD/Lang Sensori1010 Conductive061 Mixed400 ESL013 SIM_CAPD013

In review Sound Scouts: A tablet-based hearing game that: – Detects hearing problems – Indicates the most likely type of hearing problem – Recommends who to seek further help from

In summary Spatial Processing Disorder (SPD) is a well-defined type of APD SPD is commonly caused by COM, but can be fully remediated Performance on many other AP tests affected by cognitive abilities. Link between AP test scores and real-life hearing difficulties is uncertain Hearing difficulties can be managed, irrespective of diagnosis of APD Treatment of APD likely to benefit from very specific diagnoses Need for auditory processing tests less affected by cognitive abilities. 102  Difference tests

References 1.Dillon, H., Cameron, S., Glyde, H., Wilson, W., & Tomlin, D. (2012). Opinion: Re-designing the process of assessing people suspected of having central auditory processing disorders. Journal of the American Academy of Audiology (Accepted 17 June 2011). 2.Cameron, S., Glyde, H. & Dillon, H. (in press). Listening in Spatialized Noise- Sentences Test (LiSN-S): Normative and retest reliability data for adolescents and adults up to 60 years of age. Journal of the American Academy of Audiology (Accepted 18 May 2011). 3.Cameron, S. & Dillon, H. (in press). Development and Evaluation of the LiSN & Learn Auditory Training Software for Deficit-Specific Remediation of Binaural Processing Deficits in Children: Preliminary Findings. Journal of the American Academy of Audiology (Accepted 29 April 2011). 4.Cameron, S., & Dillon, H. (2010). LiSN & Learn Auditory Training Software (Version 1.1.0) [Computer software]. Sydney, NSW: National Acoustic Laboratories. 5.Brown, D., Cameron, S. Martin, J., Watson, C., & Dillon, H. (2010). The North American Listening in Spatialized Noise – Sentences Test (NA LiSN-S): Normative data and test-retest reliability studies for adolescents and young adults. Journal of the American Academy of Audiology, 21(10), Cameron,S., Brown, D., Keith, R., Martin, J., Watson, C., & Dillon, H. (2009). Development of the North American Listening in Spatialized Noise - Sentences Test (NA LISN-S): Sentence equivalence, normative data and test-retest reliability studies. Journal of the American Academy of Audiology, 20(2), Cameron, S. & Dillon H. (2009) Listening in Spatialized Noise – Sentences test (LISN-S) (Version 1.013) [Computer software]. Murten, Switzerland: Phonak Communications AG. 8.Cameron, S. & Dillon, H. (2008). The Listening in Spatialized Noise – Sentences Test: Comparison to prototype LISN test and results from children with either a suspected (central) auditory processing disorder of a confirmed language disorder. Journal of the American Academy of Audiology, 19(5), Cameron, S. & Dillon, H. (2008). Spatial hearing deficits as a major cause of auditory processing disorders: Diagnosis with the LISN-S and management options. In R. Seewald & J. Bamford, eds. A Sound Foundation Through Early Amplification Proceedings of the Fourth International Conference: Phonak AG, Switzerland, Cameron, S. & Dillon, H. (2007). Development of the Listening in Spatialized Noise - Sentences Test (LISN-S). Ear and Hearing, 28(2), Cameron, S. & Dillon, H. (2007). The Listening in Spatialized Noise - Sentences Test (LISN-S): Test-retest reliability study. International Journal of Audiology, 46,

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