Testing for Central Auditory Processing Disorders Harvey Dillon With thanks to: Sharon Cameron Helen Glyde Dani Tomlin Pia Gyldenkaerne Mridula Sharma Wayne Wilson

On the basis of evidence, what should CAPD testing and remediation services consist of?

Defining CAPD Do researchers need to define CAPD? Yes, ……. but a means not an end Do clinicians need to determine if a client has CAPD? No, concept too broad to be useful, Answer will change each time researchers change the definition What question should clinicians ask? Helps the discussion about how sounds are processed within the brain Consider implications for a clinician when the definition is changed …. Has to phone all past clients to let some know they are now no long have CAPD, and that others have acquired it!!!!!

A clinician’s question Does this child have a problem hearing or understanding sound that adversely affects him or her, and that I or anyone else can do something about? What is the specific nature of the problem? Is there a specific remediation for that problem? What general management techniques will minimize its effects? What tests should I use to determine the child’s problems?

Problems with current definitions Requirement for modality specificity and absence of other problems. Auditory processing neurons Deficient auditory skill Life consequences Consequent disabilities Trauma or failure to develop Hearing loss Language processing neurons Deficient language skill Life consequences Visual processing neurons Deficient visual skill Life consequences

Problems with current definitions 2. Arbitrariness of fail criterion Which tests to include in battery? How many tests have to be failed, in how many ears, in what combinations? What is a fail on each test?

Impact of criterion on diagnosis of CAPD Binaural fail Monaural fail Wayne Wilson

Problems with a Large Test Battery Impact on child’s attention (The tests are often very boring!!) Relevance of the normative data Statistical implications of presenting multiple tests - inflating Type II error rate. So …. how do we solve this problem??

Possible, but not very good, solutions…. 1. Tighten the pass-fail criteria on each test (e.g. 3 SD):  have to be very aberrant to fail 2. Require that the individual fail more than one test:  Only logical if CAPD is a “generalized disorder” 3. Repeat any test that produces a failed result:  Not consistent with normative data  An inefficient use of time

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

Dealing with problems in understanding speech Questionnaire / history Audiometry Measured disability Is there a problem that CAPD might explain? Exclude CAPD; Refer elsewhere No Master test battery Yes Non-specific remediation and management: Classroom placement FM use Instruction style Soundfield amplification Detailed test battery Test result interpretation leading to a disorder-specific diagnosis Disorder-specific remediation

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

What is a fail on one test? Proportion of children Test score Z-score

Test score sensitivity relative to functional listening ability Can estimate from correlation between test scores and functional ability Questionnaire scores of listening ability Educational attainment scores Test A Test B

Test score sensitivity relative to functional ability: Test A Test B

Criteria for adopting a CAPD test Test is associated with variation in functional ability High sensitivity (= ∆ 𝐹𝑢𝑛𝑐𝑡𝑖𝑜𝑛𝑎𝑙 𝑧−𝑠𝑐𝑜𝑟𝑒 ∆ 𝐶𝐴𝑃𝐷 𝑧−𝑠𝑐𝑜𝑟𝑒 ) Deviant results common in clinical population Attributes tested minimally shared with other tests in battery Test result indicates specific remediation necessary (and remediation affects real life) Time taken is small Test is minimally affected by attention, intelligence, motivation, working memory Associated with a known anatomical site and neural mechanism

Experiment 1 Dani Tomlin current PhD study Two subject recruitment groups: Children referred to Uni of Melbourne Audiology Clinic due to suspected APD (n=65) Teachers, parent, speech pathologist referral Normative group (n=47) School enrolment, open invitation Age range of 7–12 years Both groups to complete full test battery Results converted to Z scores (derived using age specific norms)

Measures obtained Dichotic Digits Test (DDT): Binaural integration (Musiek, 1993) Frequency Pattern Test (FPT): Temporal sequencing (Musiek et al, 1990) Gaps in Noise (GIN): Temporal resolution (Musiek et al, 2005) MLD: Binaural interaction (Bellis, 2003) LiSN-S: Binaural integration – spatial listening ability (Cameron & Dillon, 2006) Memory CELF-4: Forward and reverse digits Attention: BrainTrain®: Continuous Performance Test: Sustained auditory and visual attention Cognition -TONI-4: Nonverbal cognitive assessment Questionnaires and interview: Child completed LIFE questionnaire & recorded interview Parent completed Fisher checklist & written interview Teacher Evaluation of Auditory Performance (TEAP) & written interview Academic Performance - NAPLAN & WARP (reading fluency)

Relations between questionnaires Listening Capabilities Score

Relations between outcome variables

Test score sensitivity relative to functional abilities Dichotic digits - left Listening capabilities Dani Tomlin

Test score sensitivity relative to functional abilities Dichotic digits - left Listening capabilities Dani Tomlin

Test score sensitivity relative to functional abilities Dichotic digits - left Dichotic digits - right Freq pattern - left Freq pattern - right Listening capabilities Reading fluency Literacy Dani Tomlin

Test score sensitivity relative to functional abilities Gaps in noise - left Gaps in noise - right Digit span - Forward Digit span - Reversed Listening capabilities Literacy Reading fluency Dani Tomlin

Test score sensitivity relative to functional abilities LiSN-S Low Cue LiSN-S High cue MLD z score attention Listening capabilities Literacy Reading fluency Dani Tomlin

Sensitivity: Effect on outcome variable of being 1 SD below the mean on test score

FPT results highly correlated between ears

Dichotic digit results less correlated

Relationships between test scores

Correlations – outcomes and test scores P<0.01 Correlations – outcomes and test scores Literacy WARP Listen Cap L DD R DD L FPT R FPT MLD L GIN R GIN LiSN LC LiSN HC LiSN SA DS Fwd DS Rev TONI Att - 0.60 0.77 0.66 0.41 0.49 0.46 0.03 -0.12 -0.07 0.39 0.34 -0.03 0.56 0.67 0.62 0.64 0.47 0.33 0.37 0.00 0.25 0.22 0.21 0.09 0.44 0.51 0.32 Listening Cap 0.26 -0.04 0.14 0.13 0.43 0.15 0.53 0.35 0.08 0.28 0.48 0.27 -0.17 0.11 0.30 0.87 0.12 0.07 0.17 0.29 0.42 0.38 0.19 0.01 0.36 -0.19 -0.08 0.06 0.05 -0.02 0.73 0.02 0.04 -0.09 -0.05 0.18 0.16 0.24 0.59 0.31 0.23 Attention

NAPLAN literacy 1 2 3 4 5 6 7 8 9 10 11 12 L DD * R DD L FPT R FPT MLD L GIN R GIN DS Fwd DS Rev LiSN LC LiSN HC LiSN SA

What is affecting listening capabilities? TONI 0.27 DS Fwd 0.10 Listening capabilities 0.19 LDD 0.10 DS Rev 0.20 N=59 Adj R2 = 0.31 Att

What is affecting literacy? TONI But only 14 clinic participants with NAPLAN so far. 0.24 DS Fwd 0.30 0.18 NAPLAN Literacy LDD 0.16 DS Rev 0.29 N=35 Adj R2 = 0.64 Att

Importance of the presenting symptoms?

Importance of presenting symptoms MANOVA analysis: p=0.94

Importance of presenting symptoms Response by child Interpretation by observer Event Acts (inappropriately) based on what was heard Is not very smart Can’t follow instructions Child fails to understand an instruction Asks for repetition of instruction Poor concentration Does nothing Daydreams Misbehaves Badly behaved

Experiment 2 Pia Gyldenkaerne current PhD study Children referred to Macquarie Uni Audiology Clinic due to suspected APD (n=119) Teachers, parent, speech pathologist referral Age range of 7–13 years

Measures obtained Dichotic Digits Test (DDT): Binaural integration (Musiek, 1993) Frequency Pattern Test (FPT): Temporal sequencing (Musiek et al, 1990) Gaps in Noise (GIN): Temporal resolution (Musiek et al, 2005) MLD: Binaural interaction (Bellis, 2003) Memory CELF-4: Forward and reverse digits Attention: BrainTrain®: Continuous Performance Test: Sustained auditory and visual attention Cognition -TONI-4: Nonverbal cognitive assessment Questionnaire: Purpose designed – yes/no answers to 18 questions asking about difficulties in listening and its possible consequences Academic Performance: WARP (reading fluency)

Test score sensitivity relative to functional ability: Reported difficulties and reading fluency Dichotic digits - left Dichotic digits - right Freq pattern - left Freq pattern - right Reading speed Pia Gyldenkaerne and Mridula Sharma

Test score sensitivity relative to functional ability: Reported difficulties and reading speed Gaps in noise - right Brain Train attention quotient Brain Train response control quotient Binaural masking level difference Reading speed Pia Gyldenkaerne and Mridula Sharma

r > 0.40; p< 0.00005 r > 0.25; p <0 .01

Simple correlation matrix – outcome scores and test scores Reported Difficulties WARP L DDT R DD L FPT R FPT R GIN MLD TONI BT Attention Quotient - -0.57 -0.49 -0.24 -0.42 -0.44 0.28 0.11 -0.55 -0.35 0.41 0.20 0.35 -0.33 -0.07 0.50 0.43 0.42 0.49 -0.20 0.01 0.31 0.36 R DDT 0.22 0.23 -0.11 -0.00 0.07 0.27 0.86 -0.28 -0.05 0.34 -0.06 0.33 0.26 -0.02 0.12 0.04

Reported Difficulties No. of predictors DDT_L_SD DDT_R_SD FPT_L_SD FPT_R_SD MLD_SD GIN_R BT.AttQuot 1 * 2 3 4 5 6 7 No. of predictors DDT_L_SD DDT_R_SD FPT_L_SD FPT_R_SD MLD_SD GIN_R BT.AttQuot TONI.Quot 1 * 2 3 4 5 6 7 8

Criteria for adopting a CAPD test Test is associated with variation in functional ability High sensitivity (= ∆ 𝐹𝑢𝑛𝑐𝑡𝑖𝑜𝑛𝑎𝑙 𝑧−𝑠𝑐𝑜𝑟𝑒 ∆ 𝐶𝐴𝑃𝐷 𝑧−𝑠𝑐𝑜𝑟𝑒 ) Deviant results common in clinical population Attributes tested minimally shared with other tests in battery Leads to a specific diagnosis, for which remediation exists, and remediation affects real life functional ability Time taken is small Test is minimally affected by attention, intelligence, motivation, working memory, and language ability Known high reliability and critical differences Associated with a known anatomical site and/or neural mechanism

Comparison of tests against criteria LiSN-S LC/SA Dichotic digits Freq Patt Test GIN Digit span fwd Digit span reverse MLD Sens: slope re functional 4 3 2 5 6 Sens: deviant results common 7 Uniqueness re other tests 6.5 2.5 12 Specific diagnosis leading to effective proven remediation 0/10 Time taken Minimal effect of attention, working memory, intelligence, motivation, language ability 5/15 16 25 Known high reliability and small critical differences 10 ? Known anatomical site and neural mechanism 1

Diagnosis and intervention Spatial processing disorder  LiSN & Learn Auditory working memory (digit span fwd and reverse)  Memory booster or Cog Med Any other disorder causing speech in noise difficulties  dichotic digits  Remote microphone hearing aids (Hornickel and Krauss),  dichotic training (DIID or ARIA)

Thanks for listening http://capd.nal.gov.au/