The purpose of this work is to analyze the nature and behavior of cochlear nonlinearity and two-tone suppression under different conditions and at different levels. These processes may happen in the inner ear and cause certain problems with the perception of information by people and other human beings; this is why the analysis of these phenomena becomes crucially important for our study.
Another purpose of this work is to define the main concepts, which become crucially important for two-tone suppression and cochlear nonlinearity, such as the suppressed, the suppressor, and the pulsation threshold. And the final aim of this work is to find out the investigations by Duifhuis, Javel, Ravindran, and some other researchers, which have been already conducted on the same issues, clear up their strengths and weaknesses and point out the differences in these investigations and their impact on suppressive interactions.
The study under consideration is devoted to numerous methods, which help to analyze the phenomenon of cochlear nonlinearity and two-tone suppression, this is why the pulsation threshold method is considered to be the most effective one. This method is regarded as the preferred one in comparison to the masking method, because it helps to organize the information, gathered from past methods by Duifhuis and Javel, facilitates investigators’ understanding of the results, and provides the researchers with a chance to continue the investigation from many other perspectives.
The chosen pulsation threshold method has much in common with the research, conducted by Duifhuis and Houtgast, who attempted to present a suppressor and suppressed at the same me and analyze their influence on pulsation threshold. This method is also helpful due to its credibility while determining suppression effects and abilities to take into consideration different aspects and present clear results.
The results of the investigation proved that non-linear suppression was individual for each participant, this is why it was necessary to find out common characteristics of each respondent and unite them by conditions, time limitations, and surroundings. With the help of clear tables, it is possible to notice that the results, achieved in this research, are a bit similar to those, achieved by Duifhuis and Javel because they also depend on the level of the suppressor and the suppressed.
However, it is also necessary to take into consideration the fact that the suppressor frequency, used in this current research, is more accurate and used at really high levels. Duifhuis failed to use the same high levels, this is why the main purpose is not to compare past and present results, but to unite them and create another ground to continue investigating the same issue and the phenomena of two-tone suppression and cochlear nonlinearity from other perspectives.
In general, the current studies of two-tone suppression and cochlear nonlinearity were investigated and analyzed at a proper level. With the help of past researches, conducted by Houtgast, Duifhuis, and some other sophisticated scientists, their analyses and results, it was easier to start an investigation, choose proper conditions, and levels. The achieved results and author’s comments prove the possibility to continue investigating the topic of two-tone suppression and its influence on the respondents at higher levels of suppressor and under other conditions. It will create another reliable background for the analysis of problems with hearing and prevent possible damage of the cochlea and even hearing loss.