Academic background

Bernhard Laback, who has been at our department since 1999, completed his M.A. in natural-science-oriented Musicology (with a focus on psychoacoustics) at the University of Vienna in 1994. His thesis, "Der Einfluß des Saitenspektrums auf den abgestrahlten Klang der Violine", was supervised by Prof. Franz Födermayr and Doz. Dr. Werner A. Deutsch. He then earned a diploma in Sound Engineering at the Institute of Electroacoustics at the University for Music and Performing Arts in Vienna. He was awarded his Ph.D. in natural-science-oriented Musicology at the University of Vienna in 1999, with a dissertation entitled, "Effects of simultaneous masking on music perception in sensorineural hearing impairment and applications for signal processing in hearing aids" (german .pdf-version downloadable here (7904 KB)). The research for his Ph.D. was conducted at the Acoustics Research Institute, Austrian Academy of Sciences (Doz. Dr. Werner A. Deutsch), the Free University Hospital Amsterdam, (Prof. Tammo Houtgast, Dr. Ir. Niek Versfeld), and the Vienna University Hospital (ENT-Department: Prof. Fritze, Dr. DI Steurer). The supervisors of the dissertation were: Prof. Franz Födermayr, Doz. Dr. Werner A. Deutsch, Dr. Ir. Niek Versfeld, Dr. DI. Martin Steurer, and Prof. Dr. Walter Fritze. The dissertation was funded by the DOC (doctoral) grant of the Austrian Academy of Sciences. Since 2005 Bernhard Laback is the head of the Experimental Audiology and Psychoacoustics Group.

Research

B. Laback is currently working in cooperation with his colleagues Piotr Majdak, Matthew Goupell, and Michael Mihocic in the field of audiological acoustics. The emphasis of their work is on cochlear implant psychoacoustics, in particular on binaural hearing. Another focus of current and past work was on the perception of interaural time differences (ITD). The effect of ITD in the temporal fine structure of a sound, which is most important for sound localization and speech perception in noise, has been of high interest. Recently, B. Laback and his colleagues started a three-year project on the basic aspect of spectral localization cues with cochlear implants. It is financed by a grant from the Austrian Science Fund (FWF).

One aim of the work is a better understanding of basic effects in binaural hearing with cochlear implants. Another important aim is to develop new concepts of electric stimulation to improve hearing, especially binaural hearing, with cochlear implants.

An important aspect of this work is that we compare hearing abilities of cochlear implantees with those of normal-hearing listeners. Thus, many experiments are performed both with cochlear implantees and with normal(acoustic)-hearing subjects.

The Institute lab is equipped with facilities for direct and interaurally synchronized electric stimulation, for calibrated acoustic stimulation (double-walled sound booth), and for free-field testing (semi-anechoic room). Furthermore, B. Laback and his colleagues have a set-up for automated measurement of individual head related transfer functions (HRTFs).

Project list 

Teaching

Selected Publications

B. Laback is the (co-)author of several publications (refer to the full publications page of the institute). Here is a selection of recent peer-reviewed journal papers.

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• Goupell, M., Majdak, P., and Laback, B. (2010). Median-plane sound localization as a function of the number of spectral channels using a channel vocoder, J. Acoust. Soc. Am. 127, 990-1001.
• Majdak, P., Goupell, M., and Laback, B. (2010). 3-D localization of virtual sound sources: effects of visual environment,pointing method, and training, Attention, Perception, & Psychophysics 72, 454-469.
• Majdak, P., and Laback, B. (2009). Effect of center frequency and rate on the sensitivity to interaural delay in high-frequency click trains, J. Acoust. Soc. Am 125, 3903-3913.
• Goupell, M., Laback, B., and Majdak, P. (2009). Enhancing sensitivity to interaural time differences at high modulation frequencies by introducing temporal jitter, J. Acoust. Soc. Am. 2511-2521.
• Balazs, P., Laback, B., Eckel, G., and Deutsch, W. A. (2010). Time-Frequency Sparsity by Removing Perceptually Irrelevant Components Using a Simple Model of Simultaneous Masking, IEEE Trans Audio Speech Lang Processing 18, 1, 34-49.
• Goupell, M., Laback, B., Majdak, P., and Baumgartner, W. D. (2008). Current-level discrimination and spectral profile analysis in multi-channel electrical stimulation, J. Acoust. Soc. Am 124, 3142-3157.
• Laback, B., and Majdak, P. (2008). Reply to van Hoesel: Binaural jitter with cochlear implants, improved interaural time-delay sensitivity, and normal hearing, letter to Proc Natl Acad Sci USA 12, 105, 32.
• Laback, B.and Majdak, P. (2008). Binaural jitter improves interaural time difference sensitivity of cochlear implantees at high pulse rates, Proc. Natl. Acad. Sci. U S A 105, 2, 814-817. download
• Goupell, M., Laback, B., Majdak, P., and Baumgartner, W. D. (2008). Effects of frequency-place mapping and number of channels on speech intelligibility in electrical stimulation, J. Acoust. Soc. Am. 123, 2295-2309.
• Laback, B., Majdak, P., Baumgartner, W. D. (2007). Lateralization discimination of interaural time delays in four-pulse sequences in electric and acoustic hearing, J. Acoust. Soc. Am. 121, 2182-2191.
• Majdak, P., Laback, B., Baumgartner., W.D. (2006). Effects of interaural time differences in fine structure and envelope on lateral discrimination in electrical hearing, J. Acoust. Soc. Am. 120, 2190-201.
• Laback, B., Deutsch, W. A., Baumgartner, W. D. (2004). Coding of vowel-like signals in cochlear implant listeners, Journal of the Acoustical Society of America 116, 1208-1223.
• Laback, B., Pok, S. M., Baumgartner, W. D., Deutsch, W. A., Schmid, K. (2004). Sensitivity to Interaural Level and Envelope Time Differences of Two Bilateral Cochlear Implant Listeners using Clinical Sound Processors, Ear & Hearing 25, 5, 488-500.

Professional societies and activities

Member of ARO ( Association for Resarch in Otolaryngology) and the AES (Audio Engineering Society).