Intelligibility of bone-conducted speech at different locations compared to air-conducted speech

Abstract

Bone-conduction transducers offer a unique advantage for radio communication systems, allowing sound transmission while the ear canals remain open for access to environmental sounds, or plugged for blocking of environmental sounds. This study compared the intelligibility of noise-degraded speech presented through bone-conduction hearing administered at different locations, and through air-conduction. Speech intelligibility was assessed using the Diagnostic Rhyme Test. Speech intelligibility was reduced for all of the bone-conduction hearing locations, relative to air-conduction hearing. There were also differences in performance for the various bone conduction locations. These results suggest that given noise-degraded speech, the performance decrement from using bone conduction will have to be weighed against the benefits of being able to dynamically block the ear canal, or leave it open, as situations require. Further, the choice of bone conduction transducer location would need to weigh possible performance differences against the various practical advantages of each location.

References

Acker-Mills

Houtsma

A. J. M.

Ahroon

(2005). Speech intelligibility with acoustic and contact microphones. Paper presented at the New Directions for Improving Audio Effectiveness, Amersfoort, The Netherlands: NATO RTO-MP-HFM-123/RSY, Paper 07.

Acker-Mills

Houtsma

A. J. M.

Ahroon

(2006). Speech intelligibility in noise using throat and acoustic microphones. Aviation, Space, and Environmental Medicine, 77, 26–31.

Bárány

(1938). A contribution to the physiology of bone conduction. Acta Oto-Laryngologica, 26, 1–223.

Békésy

G. v.

(1960). Experiments In Hearing ( Wever

E. G.

, Trans.). New York: McGraw-Hill Book Company, Inc.

Cohen

(1983). Applied Multiple Regression/Correlation Analysis for the Behavioral Sciences (Second ed.). Hillsdale, NJ: Lawrence Erlbaum.

Gripper

McBride

Osafo-Yeboah

Jiang

(2007). Using the Callsign Acquisition Test (CAT) to compare the speech intelligibility of air versus bone conduction. International Journal of Industrial Ergonomics, 37, 631–641.

McBride

Letowski

Tran

(2008). Bone conduction reception: Head sensitivity mapping. Ergonomics, 51(5), 702–718.

Osafo-Yeboah

Gripper

McBride

Jiang

(2006). Effect of Bone Conduction Vibrator Placement on Speech Intelligibility using the Callsign Acquisition Test - a Pilot Study. Paper presented at the 2006 Annual Industrial Engineering Management Systems Conference, Cocoa Beach, FL.

Osafo-Yeboah

Jiang

Gripper

Lyons

(2006). Comparison of speech intelligibility test between air conduction and bone conduction using the callsign acquisition test. Paper presented at the Human Factors and Ergonomics Society, San Francisco, CA.

10.

Osafo-Yeboah

Jiang

McBride

Mountjoy

Park

(2009). Using the Callsign Acquisition Test (CAT) to investigate the impact of background noise, gender, and bone vibrator location on the intelligibility of bone-conducted speech. International Journal of Industrial Ergonomics, 39, 246–254.

11.

Robinette

M. S.

Cevette

M. J.

(2002). Case history, integrating audiometric results, and clinical decision analysis. In Katz

, Handbook of Clinical Audiology (5th ed., pp. 142–156). Philadelphia: Williams & Wilkins.

12.

Stanley

R. M.

Walker

B. N.

(2007). Towards a transfer function used to adjust audio for bone-conduction transducers. Journal of the Acoustical Society of America (Abstract), 123, 3565.

13.

Stenfelt

S. P. Y.

(2006). Middle ear ossicles motion at hearing thresholds with air conduction and bone conduction stimulation. Journal of the Acoustical Society of America, 119, 2848.

14.

Tonndorf

(1966). Bone conduction: Studies in experimental animals. Acta Oto-Laryngologica, Suppl. 213, 1–132.

15.

Voiers

W. D.

(1983). Evaluating processed speech using the diagnostic rhyme test. Speech Technology, 30–39.

16.

Walker

B. N.

Stanley

Iyer

Simpson

B. D.

Brungart

D. S.

(2005). Evaluation of bone-conduction headsets for use in multitalker communication environments. Proceedings of the Annual Meeting of the Human Factors and Ergonomics Society (HFES2005), Orlando, FL (26–30 September). pp. 1615–1619.