Department of Communication Sciences and Disorders Faculty and Staff

Blas Espinoza-Varas, PhD

Associate Professor

Contact Information:

Office: (405) 271-4214 Ext. 46073 Laboratory: (405) 271-4214 Ext. 46076 Fax: (405) 271-3360 Cell: (918) 894-1503 (voice mail)


Postdoctoral Research Training (Hearing Science), Department of Psychology, McGill University Montreal, Canada, Medical Research Laboratory, USA Navy, New London, Connecticut, 1982
Ph.D. Experimental Psychology (Psychoacoustics), Department of Psychology and Central Institute for the Deaf, Washington University Medical Center St. Louis, Missouri, 1978
M.A. Experimental Psychology, 1973


Professional Program:
Hearing Science
Speech Perception
Research Methods in Speech and Hearing
Seminar on Auditory Memory and Auditory Training
Research Doctoral Dissertation

Research Interests:

Auditory processing in hearing-impaired patients
Auditory attention deficits in older adults
Cortisol effects on auditory information processing
Processing of irrelevant auditory information in young and older adults
Auditory processing rate in normal and hearing-impaired young adults
Auditory training in sensorineural hearing impaired patients
Simulation of cochlear-implant current spread in normal-hearing listeners


  • Discrimination of redundant auditory cues and sensorineural hearing loss. NIH-NIDCD $ 219,750 for 12-01-06-11-30-09 .
  • Hearing high-frequency sounds with sensorineural hearing loss, NIH, IDeA Network of Biomedical Research Excellence, $5000.00 for 5-1-07 to 7-31-07
  • “Auditory neuroplasticity and sensorineural hearing loss” College of Allied Health Seed Grant, OUHSC $7,500.00 from 8/1/07 to 7/31/08.
  • Learning to hear high-frequency sounds and cochlear hearing Loss.  Presbyterian Health Foundation.  $43,988 for 9-1-06 to 8-30-07. 
  • “Effects of bipolar and monopolar current spread on speech intelligibility,” NIH Infrastructure Network for Biomedical Research Excellence, $19,964 from 9/1/07 to 8/30/08.
  • Improving speech intelligibility for cochlear implant users by selecting spectral bands that minimize the effect of noise and electrode interaction. DEPSCOR-INBRE $25,000 for 9-1-06 to 8-30-07.
  • Aging, irrelevant information, and pitch discrimination, College of Allied Health Seed Grant, $ 5,000.00 for 9/1/2004 - 8/31/2005.


Editorial Activities
Ad-hoc reviewer for Journal of Speech and Hearing Research; Perception and Psychophysics; Journal of the Acoustical Society of America


Professional Organizations
Acoustical Society of America
Audio Engineering Society
American Speech, Language, & Hearing Association
American Auditory Society

Selected Publications:

  • Espinoza-Varas, B (2008), “Resolution, spectral weighting, and integration of information across tonotopically remote cochlear regions: hearing-sensitivity, sensation level, and training effects.” In: Proceedings of the 155th Meeting Acoustical Society of America, Paris, France (Accepted).
  • Bingabr, M.G., Espinoza-Varas, B. & Loizou, P.C. (2008). “Simulating the effect of spread of excitation in cochlear implants.” Hearing Research (accepted).
  • Espinoza-Varas, B., & Jang, H. (2006). Aging impairs the ability to ignore irrelevant information in frequency discrimination tasks.  Experimental Aging Research, 32, 209-226.
  • Espinoza-Varas, B., & Jang, H. (2006). Backward-masked frequency discrimination by young and older adults: effects of masker level variability.  Acta Acoustica, 92, 457-467.
  • Espinoza-Varas, B. & Jang, H. (2005). Effects of irrelevant level fluctuation on frequency discrimination by young and older adults. Acoustical Science & Technology, 26, 394-398.
  • Espinoza-Varas, B., Bowman-Edmundson, S., & Jang, H. (2005). Effects of high-frequency amplification and training on impaired-listeners’ ability to discriminate redundant auditory cues. Journal of the Acoustical Society of America, 117, 2599.
  • Espinoza-Varas, B., & Jang, H. (2005). Masker variability effects in backward-masked frequency discrimination.  Journal of the Acoustical Society of America, 117, 2600.
  • Espinoza-Varas, B., & Jang, H. (1998). Sequential interactions in discrimination of frequency increments trailed by irrelevant frequency increments: Effects of target duration and target-irrelevant frequency separation. In: P.K. Kuhl & L.A. Crum (Eds.), Proceedings of the 16th International Congress on Acoustics. (pp.2343-2344). Seattle, Washington.
  • Espinoza-Varas, B., & Cherukuri, S.V. (1995). Evaluating a model of auditory masking for applications in audio coding. Proc. IEEE ASSP Workshop on Applications of Signal Processing to Audio and Acoustics, p. 8.4.
  • Espinoza-Varas, B. (1994). Speech and Hearing Applications of LabVIEW on the Macintosh, Instrumentation Newsletter, National Instruments, 6 (3), A-4.