Introduction: The acoustic reflex threshold is defined as the lowest sound intensity capable of starting the middle ear protection mechanism due to intense sounds (Metz, 1952; Jerger, 1970), being necessary the structural and functional integrity of the periferic and central auditory system. These structures are also responsable for the central processing of auditory information. Aim: We intend to verify whether acoustic reflex abnormalities can also appear in auditory processing (AP) disorders, resulting in symptoms related to speech and language disorders. Study design: Prospective randomized. Material and method: Data were analyzed from one hundred AP assessments, using Pereira (1997) method. Patients, male and female, with ages ranging from 07 to 18 years, had normal hearing thresholds and normal tympanograms patterns. The difference between the acoustic reflex and hearing thresholds defined the acoustic reflex level (ARL), considered normal between 70-90dB and altered when above of this range or when absent in one or more frequencies (Carvallo, 1996; 1997; Metz, 1952). Results: Disorders of AP were found in 97% of the patients. In this group, 62% showed ARL abnormalities, being statistically significant. Furthermore, patients with AP disorders showed ARL alterations, more frequently on severe degree disorders, on patients with combined auditory gnosis impairments and on patients with more than one auditory ability altered. Conclusion: Patients with acoustic reflex alterations and normal audiometry should perform the AP assessment, as these symptoms could unmask pathologies of the central nervous system.
acoustic reflex; auditory perception; normal hearing
