Identify Issues. Phase 1-4

Transcription

1 2008 David Canning

2 Identify Issues Evaluation and Dissemination Proposed plan Phase 1-4

3 Each room or other space in a school building shall be designed and constructed in such a way that it has the acoustic conditions and the insulation against disturbance by noise appropriate to its intended use. Requirement E4 from Part E of Schedule 1 to The Building Regulations 2000 (as amended). BB93 p3

4 In schools where there are children with hearing impairment the acoustic environment can be the critical variable in terms of their participation in mainstream classes: Listening to the teacher Listening to other children Listening in when working in groups A teacher should manage teaching in such a way as to ameliorate the challenges faced by a student with hearing difficulties. However, the better the acoustic conditions, the less challenging will be the situations described above. (BB93 p80)

5 Experimental Approach Generalisable Change one variable only Staff and children blind to condition Analysis of acoustic data will be carried out blind to the condition Achievable:

6 One curriculum area 4 Identical classrooms Sound treatments that are visually similar Ability to change the acoustic performance of all classrooms Staff willing to tolerate and eventually ignore measurement equipment and changing classes over a period of at least 4 months.

7 Experimental Condition British Association of Teachers of the Deaf (BATOD) (very low reverberation ) BB93 classrooms designed for HI (low reverberation time in mid frequencies) BB93 (<0.8s mid frequencies) Untreated (high reverberation time > 1s mid frequencies) Untreated Classroom A Classroom B Classroom C Classroom D Phase 1 Classroom A Classroom B Classroom C Classroom D Phase 2 Classroom C Classroom A Classroom B Classroom D Phase 3 Classroom B Classroom C Classroom A Classroom D

8 10 possible teachers 8 Teaching exclusively in one of the experimental rooms 8 Classes taught exclusively in one of the rooms Yr7 7q Yr8 8q 8r Yr9 9r 9p yr10 10t 10i 10t

9 Physical Acoustics Hearing performance Room Functional Acoustics Teacher and Child rating

10 Physical: Impulse responses Speech parameters Functional: Signal to noise levels at a child s ear level Activity sound levels

11 Speech Discrimination tests Sentence recognition scores of Hearing Impaired children and matched hearing children (8 10 mins per child) Paediatric Audiovisual Speech in noise test (3-5 mins per child)

12 Questionnaires Child questionnaires Listening Inventories in Education UK (LIFE UK) (ease of listening) Teacher questionnaires LIFE UK (ease of listening and listening behaviour) Semantic Differential Interviews Staff Children

13 32 hours audio data per phase = 128 hours 32 hours logged acoustic data and acoustic samples = 128 hours + 3 hours of acoustic samples Impulse responses for each room each phase 350 questionnaires each phase = 1400 questionnaires 22 speech discrimination sets of data per phase Interview data

14 Physical 1 -Empty Classrooms WINMLS Swept sine, Impulse response Reverberation time Early decay time Clarity Definition Speech Transmission Index (STI) ALcons

15 Axis Title Physical MA1 MA2 MA MA MA MA

16 Functional: Classes in action Norsonic N121 Sound analyser Logged sound levels Wide range of statistical measures. Acoustic logging, linked to the Logged data for absolute sound levels of acoustic events Audio recordings High quality audio recordings taken at ear level of HI (or substitute) child. Signal to noise levels of communication events

17 Functional-Active Classrooms

18 Functional-Active Classrooms Specific Teacher Class Combinations Baseline Treatment 1 Treatment 2 Treatment 3 LAeq T LA90,T

19 Functional-Active Classrooms Signal to Noise Levels: Example Teacher talking to whole class explaining new topic: Front Back Baseline Treatment Treatment 2 Treatment 3

20 Listening Inventories for Education UK version LIFE UK (adapted for secondary schools) 18 questions per test. Not all questions relate to hearing in class. Teacher LIFE Based on observable listening behaviours of specific children Semantic differential Based on work by Mies

21 Questionnaires Child questionnaires Listening Inventories in Education UK (LIFE UK) (ease 1 of listening) hi group all hi minus 2 non believable

22 Interviews Teachers External consultant Children?

23 Room Ma2 standard setup Sentence recognition test in noise Identify 50% discrimination score from a performance intensity curve BKB sentences delivered by computer Paediatric Audio Visual Speech in Noise Test Adaptive speech in noise test delivered with and without vision.

24 Key Word Percentage Correct Score BKB Sentence test (Key words scoring) % 90.00% 80.00% 70.00% 60.00% 50.00% 40.00% 30.00% hikn ha ab ha cp ha eg ha mh ha pe nh ab NH cmk NH gf 20.00% 10.00% 0.00% Signal to Noise level nh jc Nhje NH lb NHzh NH zp

25 Audiovisual Threshold Paediatric Audiovisual Speech in Noise Thresholds Phase y = x R² = 1 10 hearing aids normally hearing 0 no benefit line Audio only threshold

26 Impact of different room acoustic performances on Hearing speech, with and without lipreading Self perceived ease of listening Classroom functional acoustics Signal to noise levels Overall sound levels Speech levels Teacher reflections on teaching and learning Suitability of classes for inclusive environments School management and building issues

27 How should the findings be disseminated? How might the study be developed?

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