The Study of Implementation of the Otoacoustic Emission for Registration of the Medicamentous Influence on the Auditory Channel of Guinea Pigs

Out of the hundred infants from one to three children are born with hearing disorders or acquire it in the neonatal period. That is, when performing a screening, there is no identification of the disease, but the normal function of the hearing organ is confirmed or not confirmed. Among the important advantages of otoacoustic emissions is that this method is objective, that is, minimizes the possibility of a mistake due to the influence of the human factor on the research process. In addition, this method can be applied from the very first days of life, which gives it a rather tangible advantage over subjective methods for which the cooperation of the subject is required. One of the new methods for objective hearing research, which is actively used in audio practice, is the method of recording distortion product otosacoustic emission signals (DPOAE) generated by the structures of the cochlear of the inner ear spontaneously or in response to acoustic stimulation. Guinea pigs were used as a test subjects because their hearing organ bears high level of resemblance to the human one. The complex of the results of guinea pig hearing ability testing obtained with the usage of otosacoustic emission at the frequency of the product of distortion was considered in the study. Each reviewed situation was presented by a set of survey results for each ear of the eight guinea pigs at 6 frequencies - 2 kHz, 4 kHz, 6 kHz, 8 kHz, 10 kHz, 12 kHz, in general 96 results in the research. Guinea pigs, whose bodies have not been affected by medications, were consolidated in the control group (which is taken as a result of their normal hearing state). Thus, 40 experiments on guinea pigs under medical effects and one for the determination of normal value were performed. This paper presents 6 groups of experiments. The analysis of the results took place as follows: for each one of the frequencies used, the mean value of the amplitude was found, and definition of the deviation set the confidence interval for each experiment. A statistical analysis of the obtained results was also carried out using Student's t-criterion. The reason of its application was match of the results to samples of the normal distribution law. Subsequently, the results (including the "Norma") are compared with the criterion for passing the otoacoustic test, which is given by Ph.D. Y. K. Sokolov. In this paper were obtained experimental results of the study of the condition of the auditory channel of experimental subjects (guinea pigs), on which the directed effect of medicinal nature was carried out were estimated by applying the method of confidence intervals and their subsequent statistical analysis was conducted with the usage of the t-criterion of the Student in order to establish the possibility of using these methods for assessing the state of the auditory canal when using otosacoustic emissions at the frequency of the product of distortion. According to the analysis of the above results, it can be concluded that the numerical results obtained provide comprehensive information on the state of the hearing of the control group of animals, but they are not suitable for the purpose of evaluating the individual results of the study. From the statistical and actual results presented in the work it can be concluded that the sensitivity of the applied methods to the mean values in the frequency bands and the less sensitivity to the error values. Ref.10, fig.6, tabl. 4.