Ashley W. Harkrider, Ph.D.
Associate Professor of Audiology
Email: aharkrid@utk.edu
* Updated August 4, 2006

Dr. Ashley W. Harkrider teaches graduate courses in anatomy and physiology of the hearing mechanism, physiological assessment of the auditory system, and hearing conservation. Dr. Harkrider’s research focuses on physiological correlates of auditory perception, including electrophysiological and behavioral discrimination of consonant-vowel stimuli, the role of nicotine in the central auditory nervous system measured electrophysiologically and behaviorally in humans and physiologically in guinea pigs, relations between auditory efferent activity (acoustic reflexes, OAE suppression) and speech performance in noise, and relations between middle-ear measures, otoacoustic emissions, and auditory thresholds. Dr. Harkrider has directed several students conducting research projects in these areas (3 theses, 3 doctoral level projects, 1 dissertation, 9 graduate assistantships). She has received several research grants, most of which have targeted the study of auditory evoked potentials and otoacoustic emissions in humans. Dr. Harkrider has published research articles in Hearing Research, The Journal of the American Academy of Audiology, and The ASHA Newsletter. In addition, she has presented frequently across the United States at research meetings including The Acoustical Society of America, The Association for Research in Otolaryngology, The American Academy of Audiology, and The American Auditory Society.

EDUCATION               

University of Texas at Austin; Austin, TX (1995-1999). Doctor of Philosophy; Major Area: Communication Sciences & Disorders (Hearing Science).
University of Tennessee at Knoxville; Knoxville, TN (1993-1995). Master of Arts (with honors); Major: Audiology.
University of North Carolina at Chapel Hill; Chapel Hill, NC (1989-1993). Bachelor of Arts, Major: English, Minor: French.

COURSES TAUGHT

ASP 507 Anatomy and Physiology of Hearing
ASP 576 Physiological Assessment of Auditory Function, I
ASP 583 Physiological Assessment of Auditory Function, II
ASP 545 Sound Measurement Techniques and Hearing Conservation
Undergraduate Honors Seminar, Section 85466, Sex, Drugs, Rock-n-Roll and the Auditory System

GRANTS, AWARDS AND HONORS

National Institutes of Health, Ruth L. Kirschstein National Research Service Award, “Physiological Contributions to Noise Acceptance,” Pre-doctoral fellowship submitted by Joanna W. Tampas, sponsored by Ashley Harkrider, Submitted August 5, 2005 ($15,000).

American Academy of Audiology New Investigator Research Award. “Changes in the perception of stop consonants through frequency shaping as reflected by categorical boundaries,” Co-Investigator, P. Plyler, Submitted November 15, 2003 ($10,000).

National Science Foundation, Division of Graduate Education, Graduate Research Fellowship Program. “Smoking and sex differences in the efferent auditory system,” Mentor to Primary Student Investigator, Chris Clinard, Submitted November 3, 2003 ($44,000).

National Institutes of Health, National Institute for Deafness and Other Communication Disorders, “Acceptable noise level (ANL)/Hearing aid use,” Co-Investigators, A. Nabelek, S. Burchfield, Submitted November 1, 2003 ($1,250,000).

National Institutes of Health, National Institute for Drug Abuse, Principal Investigator for R01, “Acute Effects of Nicotine on the Auditory System,” Co-Investigators, M. Hedrick, J. Hall, Revised application to be submitted March 1, 2003 ($1,694,614).

National Institutes of Health, National Institute for Deafness and Other Communication Disorders, Co-Investigator for R01, “Sequential Effects of Two Child Language Interventions,” Principal Investigator, L. Swanson, Application submitted June 1, 2002 ($1,973,401) as part of NIDCD Investigator Initiated Clinical Trials with five universities.

University of Tennessee Professional Development Award, Division of Small Grants, Co-Investigators, M. Hedrick, J. Hall, 2002 ($12,000).

University of Tennessee Professional Development Award, Division of Small Grants, 2001 ($450).

University of Tennessee Scholarly Activity/Research Incentive Fund (SARIF), 1-year Award, 1999-2000 ($10,000).

University of Tennessee Scholarly Activity/Research Incentive Fund (SARIF), Division of Small Grants, 2000 ($600).

University of Tennessee Scholarly Activity/Research Incentive Fund (SARIF), 1-year Award, 2000-2001 ($10,000).

American Academy of Audiology Student Investigator Research Award, 1999 ($2500).

Outstanding Audiology Graduate Student Scholarship Award, Scott Haug Foundation, 1998.

Professional Development Award, University of Texas Graduate Studies, Spring 1998 ($300).

Shell Graduate Grant, College of Communication, University of Texas at Austin, Spring 1998 ($300).

University of Texas Tuition Fellowship, 1-year Award, 1997-1998 ($7000).

University of Texas Continuing Fellowship, 1-year Award, 1997-1998 ($12,000).

University of Texas Summer Tuition Fellowship, 1996, 1997, 1998.

Professional Development Award, University of Texas Graduate Studies, Spring 1997 ($150).

Shell Graduate Grant, College of Communication, University of Texas at Austin, Spring 1997 ($100).

Sertoma Club's Most Outstanding Graduate Student in Communication Sciences and Disorders, 1996-1997.

David Bruton Jr. Fellowship, University of Texas, Fall Semester Award, 1996 ($4000).

Most Outstanding Graduate Student Award in Communication Sciences and Disorders, University of Texas, 1995.

University of Texas Pre-Emptive Graduate Fellowship, 1-year Award, 1995-1996 ($12,000).
 

REFEREED PUBLICATIONS

Franklin, C., Harkrider, A.W., Hedrick, M.S. (in prep). Changes in the perception of stop consonants through enhanced cue training.

Harkrider, A.W., Plyler, P.N., Hedrick, M.S. (in review). Effects of hearing loss and spectral shaping on identification and neural representation of stop consonant stimuli. J Acoust Soc Am.

Harkrider, A.W., Tampas, J.W. (in review). Differences in physiological responses from the cochleae and central nervous systems of females with low versus high acceptable noise levels. J Am Acad Audiol.

Tampas, J.W., Harkrider, A.W. (in press). Auditory evoked potentials in females with high and low acceptance of background noise. J Acoust Soc Am.

Tampas, J.W., Harkrider, A.W., Hedrick, M.S. (in press). Comparison of behavioral discrimination, MMN, and P300 to speech and non-speech stimuli. J Sp Lang Hear Res.

Harkrider, A.W., Plyler, P.N., Hedrick, M.S. (2005). Effects of age and spectral shaping on identification and neural representation of stop consonant stimuli. Clin Neurophys, 116, 2153-2164.

Harkrider, A.W., Smith, B.S. (2005). Acceptable noise level, phoneme recognition in noise, and auditory efferent measures. J Am Acad Audiol, 16, 530-545.

Harkrider, A.W., Hedrick, M.S. (2005). Acute effects of nicotine on auditory gating in smokers and non-smokers. Hear Res, 202, 114-128.

Rogers , D.S., Harkrider, A.W., Burchfield, S.B., Nabelek, A. (2003). The influence of listener’s gender on the acceptance of background noise. J Am Acad Audiol , 14, 372-382 .

Harkrider, A.W., Champlin, C.A., McFadden, D. (2001). Acute Effects of Nicotine on Nonsmokers: I. OAEs and ABRs. Hear Res, 160, 73-88 .

Harkrider, A.W. & Champlin, C.A. (2001). Acute Effects of Nicotine on Nonsmokers: II. MLRs and 40-Hz Responses. Hear Res, 160, 89-98.

Harkrider, A.W. & Champlin, C.A. (2001). Acute Effects of Nicotine on Nonsmokers: III. LLRs and EEGs. Hear Res, 160, 99-110.

Harkrider, A.W. & Martin, F. N. (1998). Quantifying the Amount of Acoustic Radiation from the Bone-Conduction Vibrator. J Am Acad Audiol, 9, 410-416 .

INVITED PUBLICATIONS

Harkrider, A. W. (2001, October). Investigating the role of nicotinic cholinergic receptors in the human auditory system. ASHA Special Interest Division 6, Hearing and Hearing Disorders: Research and Diagnostics Newsletter, 5 (1), 3-5.

 

REFEREED PRESENTATIONS

Franklin, C., Harkrider, A.W., Hedrick, M.S. Changes in the perception of stop consonants through enhanced cue training. Accepted for presentation at the American Speech Language Hearing Association; San Diego, CA, November, 2005.

Harkrider, A.W., Plyler, P.N., Hedrick, M.S. Effects of hearing loss on behavioral and neurophysiologic measures of categorical perception. Presentation at the 149th Meeting of the Acoustical Society of America; Vancouver, B.C., Canada, May 16-20, 2005.

Harkrider, A.W., Plyler, P.N., Hedrick, M.S. Effects of aging on behavioral and neurophysiologic measures of categorical perception. Presentation at the Association for Research in Otolaryngology 2005 MidWinter Meeting; New Orleans, LA, February 19 – 24, 2005.

Harkrider, A.W. Integrating research into the Au.D. at The University of Tennessee. Presentation at the Audiology Education Summit; Fort Lauderdale, FL, January 14-16, 2005.

Smith, B., Harkrider, A.W., Burchfield, S.B., & Nabelek, A.K. Relation between measures of speech-in-noise performance and measures of efferent activity. Presentation at the 144th Meeting of the Acoustical Society of America; Nashville, Tennessee, April 28 – May 2, 2003.

Webster, J.D., Harkrider, A.W., & Hedrick, M. Comparison of behavioral discrimination, MMN, and P300 to speech and non-speech stimuli. Presentation at the 144th Meeting of the Acoustical Society of America; Nashville, Tennessee, April 28 – May 2, 2003.

Franklin, C. & Harkrider, A.W. Perceptual Cue-weighting of Voiceless Stop Consonants as Represented by Mismatch Negativity and P300. Presentation at the 143rd Meeting of the Acoustical Society of America; Pittsburgh, Pennsylvania, June 3 – 7, 2002.

Harkrider, A.W. & Hedrick, M.S. Nicotine and the Auditory Systems of Non-Smokers. Presentation at the Association for Research in Otolaryngology 2002 Midwinter Meeting; St. Petersburg Beach, Florida, January 27-31, 2002.

Harkrider, A.W. & Champlin, C.A. Acute Effects of Nicotine on Physiological Responses from the Auditory Systems of Non-Smokers. Presentation at the 139th Meeting of the Acoustical Society of America; Atlanta, Georgia, May 30-June 3, 2000.

Harkrider, A.W. & McFadden, D. Acute Effects of Nicotine on Otoacoustic Emissions in Non-Smokers. Presentation at the Association for Research in Otolaryngology 2000 Midwinter Meeting; St. Petersburg Beach, Florida, February 20-24, 2000.

Whicker, A. & McFadden, D. Relationship Between Otoacoustic Emissions and Outer and Middle Ear Measures. Presentation at the American Auditory Society Convention; Los Angeles, CA, April 1, 1998.

Whicker, A. & Martin, F. N. Quantifying the Amount of Acoustic Radiation from the Bone-Conduction Vibrator. Presentation at the American Auditory Society Convention; Fort Lauderdale, FL, April 16, 1997.

Thelin, J. W., Whicker, A. & Preissler, K. Distortion Product Otoacoustic Emissions: Response Emergence and Growth; Measures of Tuning. Instructional Course at American Academy of Audiology Convention; Salt Lake City, UT, April 21, 1996.

Whicker, A. Effects of primary-tone separation and frequency on distortion product otoacoustic emissions. Poster presentation at the American Academy of Audiology Convention; Salt Lake City, UT, April 20, 1996.
 

INVITED PRESENTATIONS

Harkrider, A.W. Nicotine as a Tool for Studying Auditory Function. Presentation at the University of Texas, Department of Communication Sciences and Disorders; Austin, Texas, September 7, 2001.

Harkrider, A.W. Acute Effects of Nicotine on the Auditory Systems of Non-Smokers. Presentation at the University of Kansas, Department of Audiology and Speech Pathology; Kansas City, Kansas, August 12, 2001.

Harkrider, A.W. Does Nicotine Affect Hearing? Presentation at the Press Conference at the 139th Meeting of the Acoustical Society of America; Atlanta, Georgia, May 31, 2000.

STUDENT RESEARCH

Ph.D. Dissertation Directed (n=1)

• The Effects of Auditory Training and Generalization on Electrophysiological and Behavioral Measures of Frequency Discrimination

M.A. Theses Directed (n=4)

• The influence of Listener’s Sex on the Acceptance of Background Noise
• Comparison of Behavioral Discrimination, MMN, and P300 to Speech and Non-Speech Stimuli
• Relations of Measures of Auditory Efferent Activity and Speech-in-Noise Performance
• Measures of Auditory Inhibition in Female Smokers and Non-Smokers

Ph.D. Level Independent Studies Directed (n=4)

• Perception of Voiceless Stop Consonants Measured by Mismatch Negativity and P300
• Electrophysiologic Differences Between Females with Low and High Acceptance of Background Noise
• Electroencephalographic and Cortical Auditory Evoked Responses in Females with Low and High Acceptance of Background Noise
• Pre-doctoral fellowship submitted to National Institutes of Health, Ruth L. Kirschstein National Research Service Award, “Physiological Contributions to Noise Acceptance.”

Committee member: M.A. Theses (n=2)

• The Intelligibility of Speech Produced by Young Children with Cochlear Implants
• The Determinants of Communication Ability in CHARGE Syndrome

Committee member: Ph.D. Level Independent Studies (n=2)

• Background Noise Acceptance as a Function of Listening Presentation Level
• Comparison of Loudness Tolerance and Acceptance of Background Noise While Listening to Speech

PERSONAL INFORMATION
Family: Husband- Robert; Children- Marshall ( 2 1/2)
Enjoys: Running, golfing, gardening, reading, watching UNC basketball and TN and TX football
Favorite places: NC mountains, Texas hill country

CONTACT DETAILS
Ashley Whicker Harkrider, Ph.D.
Department of Audiology and Speech Pathology
University of Tennessee
578 South Stadium Hall
Knoxville, TN 37996-0740

Phone: (865) 974-1810
Lab Phone: (865) 974-6165
Fax: (865) 974-1539

Email: aharkrid@utk.edu

 Human Auditory Physiology Laboratory

CURRENT RESEARCH:

• Actions of Nicotine in the Auditory System; A series of studies conducted with Dr. Mark Hedrick and Dr. Jim Hall investigating whether nicotinic acetylcholine receptors in the central auditory nervous system contribute to one’s ability to pull speech sounds out of background noise (stimulus filtering). To test this, behavioral and electrophysiological responses (N1-P2/MMN/P300) to relevant and distracting stimuli in the presence and absence of nicotine are being measured with the same set of non-smoking and smoking subjects. Single-cell and surface recorded responses are being made in guinea pigs as an animal model to explain the neural mechanisms responsible for the acute actions of nicotine seen in human responses. (Pilot data for grant applications to NIDA)

• A New Look at Acoustic Reflex Thresholds; Received UT Professional Development Award with Dr. Jim Thelin to study the lowest parameter of acoustic reflex threshold using an innovative averaging technique.

• Contributions to evoked otoacoustic emission (EOAE) variability in responses from the normal-hearing population; specifically, the effects of subject sex, hormonal levels, ear canal volume, static admittance, spontaneous OAEs, and efferent activity on EOAEs

• Sequential Effects of Two Child Language Interventions; collection and analysis of evoked potentials (N400/P500) in children with Specific Language Impairment (SLI) before and after treatment with FastForward and/or Narrative-Based Language Intervention (NBLI); UT co-investigator for clinical trials with Dr. Lori Swanson in collaboration with Dr. Marc Fey and three other university sites. (Grant application submitted to NIDCD in June 2002.)

• Contributions to Individual Variability in Speech Performance in Noise; Specifically, how does a subject’s sex, personality, acceptance of background noise, level of efferent activity (suppressed EOAEs, acoustic reflexes), and other factors affect their speech performance in noise? Why do some normal-hearing individuals have more difficulty in noise than others?
   

Lab Description:

The Auditory Research Laboratory (ARL) is housed in the Department of Audiology and Speech Pathology. Two sound-treated rooms are located in the ARL. Equipment is available to synthesize and generate sound digitally. Responses to sounds can be measured behaviorally, acoustically, or physiologically using commercial and custom-made data acquisition systems. The ARL contains IBM-compatible computers plus related hardware. Software is available to carry out all current forms of data analysis. Two computer workstations are available for students conducting research projects in the ARL. The ARL is connected to the University's mainframe computers via an Ethernet network.