**Glossary**

auditory system, primarily in situations involving the use of the speech spectrum [50]. A comparison between speech suppression using a standard sentence and the "happy birth‐ day" song revealed that the suppression effect was lower with the song, possibly because it involved automatic predictable speech, given that the song is universally known. In this case, attention to the suppressor stimulus was lower, causing fewer changes in cochlear activity and a smaller reduction in OAEs amplitude. However, to confirm this hypothesis, more research using speech as suppressor stimulus is needed, since we found no studies along these lines. Another study aimed at determining the best conditions to assess the efferent auditory system. The authors assessed 11 adults with normal thresholds, using three suppressor stimuli: clicks, narrow band noise, and pure tones. It was found that the click and pure‐tone stimuli were the most and least effective suppressors, respectively [47].

The authors concluded that suppressing TEOAEs in normal listeners is more effective at low frequencies, specifically at 1000–1500 Hz. Moreover, the efferent activity of the auditory system is more efficient when suppression involves a speech stimulus, com‐ pared to white noise, which has no significant effect. The efferent auditory system is more alert and attentive to standard speech stimuli, but less efficient when this speech is auto‐

The experience of conducting this study was very rewarding and indeed resulted in important findings for a more detailed investigation. For example, a reasonable variability was observed in TEOAE amplitudes, regardless of the presence of a suppressor stimulus using the same testing standards (same ear, same professional, same acoustic environ‐ ment, etc.). This variability was observed when the tests were repeated. To minimize this problem, the tests were repeated three times and the average computed. However, future studies will involve five repetitions to decrease variability and provide even more consistency. Furthermore, posttraining results were not statistically significant, possibly due to the short duration. Data in the literature suggest the need for more robust training that can guarantee better learning on the test, in order to be able to observe differences

Given that the ability to recognize speech is one of the most important measurable aspects of auditory function, the tests used in clinical practice are of the utmost importance for audio‐

Studies that allow more thorough assessment of individuals with speech comprehension dif‐ ficulties in noise should be encouraged, since understanding the entire mechanism involved in this dynamic, from sound detection to comprehension, will make it possible to standardize

auditory tests and design therapies for specific stimulations.

Speech, however, was not considered.

*2.2.1. Personal experience regarding the present study*

matic [39].

52 Advances in Clinical Audiology

[34, 45–48].

logical diagnosis.

**3. Final considerations**

dB—decibels dB SPL—decibels sound pressure level dB SL—decibels sensation level. The amount in decibels by which a stimulus exceeds the hearing threshold OHC—outer hair cells HINT—hearing in test noise Hz—Hertz IHC—inner hair cells OAEs—otoacoustic emissions TEOAEs—transient evoked otoacoustic emissions
