Tinnitus is associated with reduced sound level tolerance in adolescents with normal audiograms and otoacoustic emissions.
Recent neuroscience research suggests that tinnitus may reflect synaptic loss in the cochlea that does not express in the audiogram but leads to neural changes in auditory pathways that reduce sound level tolerance (SLT). Adolescents (N = 170) completed a questionnaire addressing their prior experience with tinnitus, potentially risky listening habits, and sensitivity to ordinary sounds, followed by psychoacoustic measurements in a sound booth. Among all adolescents 54.7% reported by questionnaire that they had previously experienced tinnitus, while 28.8% heard tinnitus in the booth. Psychoacoustic properties of tinnitus measured in the sound booth corresponded with those of chronic adult tinnitus sufferers. Neither hearing thresholds (≤15 dB HL to 16 kHz) nor otoacoustic emissions discriminated between adolescents reporting or not reporting tinnitus in the sound booth, but loudness discomfort levels (a psychoacoustic measure of SLT) did so, averaging 11.3 dB lower in adolescents experiencing tinnitus in the acoustic chamber. Although risky listening habits were near universal, the teenagers experiencing tinnitus and reduced SLT tended to be more protective of their hearing. Tinnitus and reduced SLT could be early indications of a vulnerability to hidden synaptic injury that is prevalent among adolescents and expressed following exposure to high level environmental sounds.
University of São Paulo School of Medicine, São Paulo, Brazil.|Instituto Ganz Sanchez, São Paulo, Brazil.|Association of Interdisciplinary Research and Divulgation of Tinnitus, São Paulo, Brazil.
Tanit Ganz
TG
Sanchez
Instituto Ganz Sanchez, São Paulo, Brazil.
Fernanda
F
Moraes
Instituto Ganz Sanchez, São Paulo, Brazil.
Juliana
J
Casseb
Instituto Ganz Sanchez, São Paulo, Brazil.
Jaci
J
Cota
Association of Interdisciplinary Research and Divulgation of Tinnitus, São Paulo, Brazil.
Katya
K
Freire
Department of Psychology Neuroscience and Behaviour, McMaster University, Hamilton, Ontario, Canada.
Larry E
LE
Roberts
D000161:Acoustic Stimulation; D000293:Adolescent; D001301:Audiometry, Pure-Tone; D001309:Auditory Threshold / Q000502:physiology*; D002648:Child; D003051:Cochlea / Q000502:physiology* / Q000503:physiopathology; D005260:Female; D006317:Hearing Loss, Noise-Induced / Q000209:etiology / Q000503:physiopathology*; D006801:Humans; D009622:Noise / Q000009:adverse effects; D017084:Otoacoustic Emissions, Spontaneous / Q000502:physiology*; D011571:Psychoacoustics; D013016:Sound; D011795:Surveys and Questionnaires; D014012:Tinnitus / Q000503:physiopathology*