title: From otoacoustic emission to late auditory potentials P300: the inhibitory effect.
abstract: This study verifies the effects of contralateral noise on otoacoustic emissions and auditory evoked potentials. Short, middle and late auditory evoked potentials as well as otoacoustic emissions with and without white noise were assessed. Twenty-five subjects, normal-hearing, both genders, aged 18 to 30 years, were tested . In general, latencies of the various auditory potentials were increased at noise conditions, whereas amplitudes were diminished at noise conditions for short, middle and late latency responses combined in the same subject. The amplitude of otoacoustic emission decreased significantly in the condition with contralateral noise in comparison to the condition without noise. Our results indicate that most subjects presented different responses between conditions (with and without noise) in all tests, thereby suggesting that the efferent system was acting at both caudal and rostral portions of the auditory system.
authors.affiliation: School of Medicine, Sao Paulo University, Sao Paulo, Brazil. eschocha@usp.br.
authors.forename: Eliane
authors.initials: E
authors.lastname: Schochat
authors.forename: Carla Gentile
authors.initials: CG
authors.lastname: Matas
authors.forename: Alessandra Giannella
authors.initials: AG
authors.lastname: Samelli
authors.forename: Renata Mota
authors.initials: RM
authors.lastname: Mamede Carvallo
mesh_terms: D000161:Acoustic Stimulation; D000293:Adolescent; D000328:Adult; D004569:Electroencephalography; D018913:Event-Related Potentials, P300 / Q000502:physiology*; D005072:Evoked Potentials, Auditory / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D009433:Neural Inhibition / Q000502:physiology*; D009622:Noise; D017084:Otoacoustic Emissions, Spontaneous / Q000502:physiology*; D011930:Reaction Time / Q000502:physiology; D055815:Young Adult