Cognition and Hearing Loss. Dept. of ENT/Audiology EMGO Institute for Health and Care Research VU University Medical Center Amsterdam

Transcription

1 Cognition and Hearing Loss Sophia E. Kramer Adriana A. Zekveld Dept. of ENT/Audiology EMGO Institute for Health and Care Research VU University Medical Center Amsterdam

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3 db Hearing impairment: Pure tone audiogram Speech Reception Threshold in Noise (SRTn test)

4 SRTfluc (db SNR) WORSE Speech Reception Threshold as function of Pure Tone Thresholds PTA (0.5, 1,2,4 khz) (db HL)

5 Cognitive processing load during listening Role of cognitive abilities in listening Interindividual differences in performance, reported fatigue, rehabilitation success Quantification of cognitive processing load

6 New field of science emerged Cognitive Hearing Science Linköping, Sweden (Rönnberg, Rudner, Lunner, Lyxell) Toronto, Canada (Pichora-Fuller) Bloomington, USA (Humes, Pisoni) Boston, USA (Wingfield, Tun) Amsterdam, Netherlands (Zekveld, Koelewijn, Kramer)

7 Ease of Language/Speech Understanding (ELU; ESU) mismatch Rönnberg et al., 2008

8 Speech comprehension is a complex process it involves cognitive processes and capacity! Top down Bottom up

9 Components of speech perception Pure tone threshold / audibility Suprathreshold: spectral & temporal resolution Binaural hearing (interaction both ears) Speed of processing Use of context (syntactic, semantic, context of conversation) Working memory Inhibition of irrelevant information Linguistic Closure

10 Speed of processing Linguistic Closure Linguistic Context Inhibition Working Memory

11 Speed of processing Manipulation of speech rate: I don t speak too fast, you are listening too slowly! 172 words / minute 215 words / minute 285 words / minute Speed Intelligibility This effect is larger in older listeners: processing of speech is slower in older than in younger listeners (Tun et al. 1992, Tun, 1998))

12 Cognitive functions...

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14 Use of context A bicylce has two.. The color of my coat was.. A large number of people were. With age Wingfield et al.

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16 Inhibition Green Red Yellow

17 Inhibition important when someone needs to ignore a disturbing sound source, such as an interfering speaker in the background

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19 Working memory Reading Span Test De horses were running His friend told a story The dog was selling boots X The neighborhood walked miles X For a review see Akeroyd, 2008; Besser et al., 2013

20 Working Memory Demo Hands on!

21 Working memory strongly correlated to age with age Besser et al., 2013

22 Better Speech in noise performance Correlation between Working Memory and Speech Intelligibility in hearing impaired listeners (Lunner, 2003; Foo et al. 2007; Rudner et al., 2008) 8 Correlation: r = S NR Hagerman with hearing aid (db ) Low WM capacity High WM capacity RE A DING S P A N (% correct) Regression 95% confid. Better WM performance

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24 (Clinical) test to assess the top-down component

25 disentangle modality-specific auditory processes from more global cognitive functioning (McFarland and Cacace, 1995; Watson et al., 1996; Pichora-Fuller et al., 2005; Humes et al., 2007)

26 Speech-Reception-Threshold in noise * List of short everyday Dutch sentences Masking noise Adaptive procedure SRT: threshold at which 50% correctly reproduced * (Plomp & Mimpen, 1979)

27 Visual analogue: Text Reception Threshold (TRT) test

28 Zekveld et al., JSLHR 2007

29 Visual analogue 28% unmasked text 34% 40% 46% 52% 58% 64% 70% TRT score: percentage unmasked text needed to read 50% of the sentences correctly

30 Series of experiments

31 N = 34 adults, normally hearing, (corrected to) normal vision Age: years (M=34, sd 18.4), R = 0.54 (p < 0.01) R = 0.54 (p < 0.01) Zekveld et al., JSLHR, 2007

32 Results (cont) (Hearing impaired, N=21) Stepwise multiple regression analysis (To predict the outcome on the Speech-in-Noise test) Predicotor Cum R² Multipele R Step 1 Temporal Acuity 0.48 Step 2 Text-Reception-Test % 0.85 George et al., JASA, 2007

33 SRT and TRT equivalent? About 30% of the interindividual variance in both the TRT and SRT appears to be associated with modality aspecific cognitive and linguistic skills TRT may be clinically relevant to determine part of the origin (auditory or non-auditory) of deteriorated speech reception among hearing impaired listeners

34 Contribution cognition to speech intelligibility -2-4 SRT-modulated [db SNR] auditory TRT-bars [% text]

35 Role of cognition in hearing is evident: it calls for a focus shift Cognitive functions emphasize importance of hearing strategies: - Speak slowly, articulate well - Provide context! - Reduce background noise -..

36 Contribution cognitive functions to hearing aid fitting/evaluation So far, few studies looked at - Time compression - Different types of background noise - Noise reduction - Hearing aid use - Hearing aid benefit

37 A few facts: Hearing aid use and hearing aid benefit in individuals with lower cognitive abilities (who are less able to exploit their cognitive abilities to compensate for their hearing loss) Humes (2003), Humes & Wilson (2003), Pichora-Fuller & Singh (2006), Davis (2003)

38 A few facts: Cognitive functions better predict aided speech understanding than pure tone thresholds. in particular when speech is masked by a fluctuating masker and with fast compression (difficult listening conditions) Gatehouse et al., 2003, 2006; Lunner, 2003; Lunner & Sundewall-Thoren, 2007; Lunner et al., 2009

39 Explained variance Cognitive factors may emerge in aided complex listening situations Variation in SRTnoise scores explained by PTA and cognition Explained SNR variance from hearing loss and cognitive performance 45% 40% 35% 30% 25% 20% HTL average ( khz) PTA(6) Working Memory test VLM 15% 10% 5% 0% Slow&Unmod. Slow&Mod. Fast&Unmod. Fast&Mod. Test condition Lunner & Sundewall-Thoren, 2007

40 Fast versus slow compression Individuals with better cognitive best served with fast time constants Individuals with poor cognitive abilities best served with slow time constants Gatehouse et al., 2006; Lunner & Sundewall-Thoren, 2007

41 A few facts: Those with high working-memory capacity were better than those with low capacity at identifying and reporting the specific processing effects of the aid.. (through a diary) Lunner, 2003

42 A few facts: Cognition and noise reduction Noise reduction: the intelligibility of speech decreases when there is background noise,..however.. it increases speech recall Sarampalis, et al., 2010

43 Conclusion: The relation between cognition and hearing aid/benefit isn t clear yet: There is an interaction between Cognition Listening conditions Hearing aid characteristics

44 Conclusion: Different (cognitive) tests are used throughout studies Conflicting evidence. More research is needed before a measure of cognitive functioning can be implemented in clinical practice...

45 THANK YOU!