F2–F3 enhancement improves sentence recognition for N95-muffled speech in noise
Combined F2–F3 enhancement provides broader and more consistent benefits than F2 enhancement alone under compounded degradation.
Read the publication →Hearing Science · Clinical Audiology · AuD Education
Assistant Professor & Dispensing Audiologist
Department of Communication Disorders and Sciences
California State University, Northridge
Dr. Li’s research focuses on speech perception in noise and the development of speech-enhancement strategies. He supervises the CSUN Hearing Science Laboratory and contributes to the field as a topic editor and reviewer for several peer-reviewed journals. Drawing on his experience as an ASHA-certified and California-licensed audiologist, he integrates clinical perspectives into teaching, research mentorship, and student supervision in CSUN’s Au.D. program.

Featured Research
Combined F2–F3 enhancement provides broader and more consistent benefits than F2 enhancement alone under compounded degradation.
Read the publication →The group difference remains consistent across modulation rate, carrier frequency, and stimulus duration, indicating a stable limitation in fine-grained frequency-change sensitivity.
Read the publication →Research
Program vision
How can behavioral, neural, and signal-processing approaches improve speech perception under degraded listening conditions?
Primary research area
Developing targeted signal-processing strategies to improve speech perception under degraded listening conditions, including background noise, face-mask attenuation, and hearing loss.
Selected topics: Formant enhancement for natural and N95-muffled speech; combined F2–F3 enhancement; effects of noise type, signal-to-noise ratio, and listener characteristics.
Research foundation
Examining how language experience and atypical pitch processing shape speech perception. This work distinguishes language-specific category mapping from basic acoustic sensitivity in bilingual listeners and investigates how congenital amusia affects speech and pitch processing.
Selected topics: Second-language vowel category formation and speech perception in noise; formant-cue sensitivity and masking release; vowel and lexical-tone identification; and frequency-modulation processing in pure amusia and tone agnosia.
Growing research area
Using auditory brainstem responses and frequency-following responses to investigate the neural encoding of speech and complex sounds.
Selected topics: Effects of speech content and spectral and temporal modulation on cABR/FFR; development of clinically relevant electrophysiological measures.
Research grants
Publications
A complete publication record spanning speech enhancement, speech perception in noise, auditory psychophysics, congenital amusia, and clinical auditory science.
Selected academic presentations
Selected presentations at national and international meetings in acoustics, audiology, and speech-language-hearing sciences.
Poster presentation, 190th Meeting of the Acoustical Society of America, Philadelphia, Pennsylvania.
Poster presentation, 6th Joint Meeting of the Acoustical Society of America and the Acoustical Society of Japan, Honolulu, Hawaii.
Poster presentation, AAA 2025 + HearTECH Expo, New Orleans, Louisiana.
Keynote presentation, U.S. Chinese Scholars Association Convention, Ontario, California.
Oral technical-session presentation, American Speech-Language-Hearing Association Convention, Boston, Massachusetts.
Poster presentation, 184th Meeting of the Acoustical Society of America, Chicago, Illinois.
Poster presentation, 177th Meeting of the Acoustical Society of America, Louisville, Kentucky.
Teaching & mentorship
Teaching, research advising, and clinical education in the CSUN Doctor of Audiology (Au.D.) Program.
Clinical Practice & Supervision
American Speech-Language-Hearing Association
CCC-A · Issued 2022
California Speech-Language Pathology & Audiology & Hearing Aid Dispensers Board
Clinical training experience includes Baylor Scott & White Medical Center, the UT Speech & Hearing Center, Austin ENT Associates, Texas School for the Blind and Visually Impaired, and Sonova Group.
At CSUN, he provides clinical supervision in hearing assessment, electrophysiology, vestibular evaluation, and related audiology services at the Language, Speech, and Hearing Center.
Leadership & professional service
Leads laboratory research, student mentoring, and project development.
Has served as primary advisor for more than 20 Au.D. capstone research projects.
Editorial service for Frontiers journals and the Journal of Speech, Language, and Hearing Research.
Reviewer for JSLHR, Frontiers in Psychology, JMIR journals, and the Journal of Psycholinguistic Research.
Supported program operations and academic leadership from January through May 2026.
Advises student leadership, professional development activities, and engagement with the audiology community.
Supports organizational leadership, academic exchange, and professional collaboration.
Advises student leadership, cultural programming, and campus engagement.
Collaboration
I welcome collaborations involving speech enhancement, hearing technology, speech-in-noise perception, FFR/cABR, clinical validation, and behavioral–neural relationships.