1. José Juan Barajas de Prat Clinica Barajas, Universidad de La Laguna, Fundación Dr. Barajas SANTA CRUZ DE TENERIFE - CANARY ISLANDS - SPAIN Universidad de La Laguna IAPA 2010 Symposium 19-22 September, Krakow, Poland Loudness and Auditory Steady State Responses

2. CATEGORICAL LOUDNESS SCALING

3. AUDITORY BRAINSTEMRESPONSES AUDITORY BRAINSTEM RESPONSES

4. Serpanos (1997) Relationship between Loudness Intensity Functions and the Click-ABR Wave V Latency

5. Frequency Specific Fast Fast Objective Objective AUDITORY STEADY-STATERESPONSES AUDITORY STEADY-STATE RESPONSES

6. Acoustic Stimuli: AM Tones.5, 1, 2 & 4 Khz. 70 dB nHL - Threshold ASSRs RECORDING PROCEDURE Amplifier: Low Cut: 20 Hz High Cut: 300 Hz Gain: 100 000 Notch: On Electrode Arrangement: Non-inverted: Cz Inverted:1M Ground: forehead Impedance < 5k

7. CONTOUR TEST LOUDNESS CATEGORIES 7. Uncomfortably Loud 6. Loud, but O.K. 5. Comfortable, but Slightly Loud 4. Comfortable 3. Comfortable, but Slightly Soft 2. Soft 1. Very Soft Cox, Robyn M.; Alexander, Genevieve C.; Taylor, Izel M.; Gray, Ginger A. The Contour Test of Loudness Perception. Ear & Hearing: Volumen 18(5) October 1997 pp388-400.

8. ASSR Recordings Loudness Growth Function

9. 500 Hz 1000 Hz 2000 Hz 4000 Hz Intensity (dB HL) Loudness Category Loudness Growth Function

10. Amplitude (nV) Intensity (dB HL) ASSR Amplitude-Intensity function

11. Amplitude (nV) Intensity (dB HL) ASSR Amplitude-Intensity function 500 Hz

12. Amplitude (uV) Intensity (dB HL) ASSR Amplitude-Intensity function 500 Hz 1000 Hz

13. Amplitude (nV) Intensity (dB HL) ASSR Amplitude-Intensity function 1000 Hz 500 Hz 1000 Hz 2000 Hz

14. Amplitude (nV) Intensity (dB HL) ASSR Amplitude-Intensity function 500 Hz 1000 Hz 2000 Hz 4000 Hz

15. Linear regression analysis.5 kHz 1 kHz 2 kHz 4 kHz Total Y Intercept 1.861.531.411.421.55 Slope12.2632.1328.0727.4624.9 Correlation coefficient (R) 0.47**0.45**0.52**0.68**0.49** Standard error of estimate 1.541.471.521.391.48 ** P < 0.0001 Loudness (fo) = 1.55 + 24.9 * Amplitude

16. PREDICTION OF LOUDNESS GROWTH FUNCTION FROM THE ASSR Predicted Loudness (fo) = B 0 + B 1 * Intensity + B 2 * Amplitude Y = 0.75X 0.4 Zenker Castro, Franz, Juan Barajas de Prat, Jose and Larumbe Zabala, Eneko (2008). Loudness and auditory steady-state responses in normal-hearing subjects. International Journal of Audiology, 47:5, 269 — 275.

17. Unconfortable Loudness Level

18. Unconfortable Loudness Level Objective estimation Kiessling, Audiology, 1980 Thornton, Scand Audiol, 1989 Acoustic Reflex Auditory Brainstem Response

19. ULLs Measurement Procedure 500 Hz 3 kHz Acoustical Spectrum Electrical Waveform 500 Hz 3 kHz

20. ULL = 90 dB HL ULL 500 Hz Right ear Left ear ASSR Recordings

21. 500 Hz Amplitud-Intensity function (n = 8)

22. 3 kHz Amplitud-Intensity function (n = 8)

23. Inter subject average amplitude- intensity function (n = 8)

24. Conclusions High intersubject variabilty in the amplitude-intensity function was found. ULL prediction based solely on individual ASSR amplitude-intensity function proved to be problematic.

25. THANK YOU Universidad de La Laguna Loudness and Auditory Steady State Responses José Juan Barajas de Prat Clinica Barajas, Universidad de La Laguna, Fundación Dr. Barajas SANTA CRUZ DE TENERIFE - CANARY ISLANDS - SPAIN