[P300 in subjects with hearing loss].

BACKGROUND

behavioral and electrophysiological evaluations contribute to the understanding of the hearing system and to the intervention process.

AIM: to investigate the occurrence of P300 in subjects with congenital severe to profound hearing loss, according to the variables of gender, age and hearing loss level.

METHOD: the design of this research is a descriptive transversal study. Twenty-nine subjects, 15 male and 14 female, ranging in age from 11 to 42 years, were evaluated. Inclusion criteria were: to have at least 11 years of age and no more than 45 years; to have the diagnosis of congenital severe to profound sensorineural hearing loss; to have no other disorder; and absence of central hearing loss or any other auditory conductive disorder. The first stage consisted of an auditory behavioral and physiological evaluation, including: pure tone audiometry (air and bone conduction measures), speech audiometry, SDT (Speech Detection Threshold) and functional gain measures for the subjects using hearing aids, and immittance measures--tympanometry and acoustic reflexes thresholds; transient evoked otoacoustic emissions (TEOAE); distortion product otoacoustic emissions (DPOAE). The electrophysiological evaluation was the fourth stage of the study and included: auditory brainstem response (ABR) and late latency response (P300).

RESULTS

P300 was obtained for 17 out of the 29 subjects. Mean latency and amplitude were 326.97 ms and 3.76 V, respectively. A statistical significant difference was observed for latency when considering the variable age (electrode CzA2 p < 0.003 and CzAI p < 0.02) and for amplitude when considering the variable hearing loss level (p < 0.0015).

CONCLUSION

P300 can be recorded in subjects with hearing loss.