title: Cortical signal-in-noise coding varies by noise type, signal-to-noise ratio, age, and hearing status.
abstract: The purpose of this study was to determine the effects of noise type, signal-to-noise ratio (SNR), age, and hearing status on cortical auditory evoked potentials (CAEPs) to speech sounds. This helps to explain the hearing-in-noise difficulties often seen in the aging and hearing impaired population. Continuous, modulated, and babble noise types were presented at varying SNRs to 30 individuals divided into three groups according to age and hearing status. Significant main effects of noise type, SNR, and group were found. Interaction effects revealed that the SNR effect varies as a function of noise type and is most systematic for continuous noise. Effects of age and hearing loss were limited to CAEP latency and were differentially modulated by energetic and informational-like masking. It is clear that the spectrotemporal characteristics of signals and noises play an important role in determining the morphology of neural responses. Participant factors such as age and hearing status, also play an important role in determining the brain's response to complex auditory stimuli and contribute to the ability to listen in noise.
authors.affiliation: National Center for Rehabilitative Auditory Research, VA Portland Health Care System, 3710 SW US Veterans Hospital Road, P5-NCRAR, Portland, OR 97239, United States of America; Audiology Program, School of Rehabilitation Sciences, Faculty of Health Sciences, The National University of Malaysia, Jalan Raja Muda Abdul Aziz, 50300 Kuala Lumpur, Malaysia. Electronic address: nashrah@ukm.edu.my.
authors.forename: Nashrah
authors.initials: N
authors.lastname: Maamor
authors.affiliation: National Center for Rehabilitative Auditory Research, VA Portland Health Care System, 3710 SW US Veterans Hospital Road, P5-NCRAR, Portland, OR 97239, United States of America; Department of Otolaryngology, Oregon Health & Science University, 3181 SW Sam Jackson Park Road, PV01, Portland, OR 97239, United States of America. Electronic address: Curtis.Billings2@va.gov.
authors.forename: Curtis J
authors.initials: CJ
authors.lastname: Billings
mesh_terms: D000161:Acoustic Stimulation / Q000379:methods; D000293:Adolescent; D000328:Adult; D000367:Age Factors; D001303:Auditory Cortex / Q000502:physiology*; D001307:Auditory Perception / Q000502:physiology; D005072:Evoked Potentials, Auditory / Q000502:physiology*; D005260:Female; D006309:Hearing / Q000502:physiology*; D006319:Hearing Loss, Sensorineural / Q000503:physiopathology*; D006801:Humans; D008297:Male; D009622:Noise / Q000009:adverse effects; D059629:Signal-To-Noise Ratio; D013067:Speech Perception / Q000502:physiology; D055815:Young Adult
keywords: Aging; Cortical auditory evoked potentials; Electrophysiology; Hearing loss; Masking; Noise type