Distortion product growth function in schoolers

• Grant number: 19/11961-8
• Support type: Scholarships in Brazil - Scientific Initiation
• Effective date (Start): August 01, 2019
• Effective date (End): July 31, 2021
• Field of knowledge: Health Sciences - Speech Therapy
• Principal researcher: Renata Mota Mamede Carvallo
• Grantee: Patricia Kimiko Kumagai
• Home Institution: Faculdade de Medicina (FM). Universidade de São Paulo (USP). São Paulo , SP, Brazil

Abstract

Otoacoustic emissions have the objective of evaluating the cochlea functioning mainly of the outer hair cells (OHC), helping in the audiological diagnosis of cochlear lesions. The Input/Output Growth Function provide information about the threshold and the nonlinear mechanisms within the cochlea that are associated with OHC. Auditory processing is the ability to transform acoustic energy into information for understanding to occur. Therefore, the temporal auditory processing refers to the individual's ability to perceive changes in sound characteristics, such as duration, intensity, frequency, and pauses between stimuli. Objective: The aim of this study was to analyze the difference in the thresholds for Distortion Product Otoacoustic Emissions (DPOAE), as well as the profile and compression ratio of DPOAE growth function in schoolchildren with and without alterations in temporal resolution abilities. Methodology: 30 children in the age group of 8 to 12 years will participate in the study, 15 with alterations in temporal resolution tests and 15 without complaints and without auditory changes. An initial anamnesis will be performed, tympanometry with 226Hz probe tone, acoustic reflexes in the frequencies of 500 and 4000 Hz, tonal audiometry for threshold search (dBHL) in frequencies of 250 to 8000 Hz, temporal resolution test and, record of the DPOAE, including the growth curve function, as well as the DPOAE threshold for three different frequencies of f2, respectively 2002, 3174, 4004 Hz. The stimuli will be presented in the stimulus intensity f2 (L2) ranging from 20 to 65dB NPS in steps of 3 dB and the intensity level of the stimulus f1 (L1) will vary according to the formula: L1 = 0.4L2 + 39 dB. The data will be treated statistically, adopting a level of significance of 5%.