“Speech bananas” are not afternoon snacks for audiologists.It’s a reference to the placement of sounds in an audiogram – a graphical representation of an individual’s hearing acuity within a range of volumes and frequencies. Audiograms are typically graphed with the frequency level ( in Hertz) on one axis and volume level ( in Decibels) on the y axis.
When the common sounds of human speech are graphed on this kind of audiogram, they have a tendency to all cluster within an region of the graph that is in the shape of a banana. Nearly the whole alphabet and most letter combinations (such as ng, th, sh and ch) cluster into the speech banana range. The principal exceptions are the letters q, w, x, and y.
The speech banana is extremely important because it includes most of the sounds of human language which is essential for our communications with one another. Individuals with normal hearing, can also hear many sounds outside of the banana such as high frequency leaves rustling or low frequency fog horns. It is quite common for individuals to have trouble hearing or understanding letter combinations such as ng, th, sh and ch and certain vowels.
This is why hearing professionals are most concerned by hearing loss inside the spectrum represented by the speech banana. If an audiogram exposes that an individual has hearing loss within the speech banana region, it is almost certain that they’re having oral communication problems.
The range of spoken sounds encompassed by the speech banana is so critical to communications, that a number of school districts mandate hearing checks using audiograms to identify hearing impairments in this region. This is also one of the reasons why it is so important to have your hearing aids properly programmed and adjusted by a qualified hearing specialist or audiologist, who can make sure that you are hearing sounds within this speech banana area as clearly as possible. In case you have any worries about your hearing in the speech banana range,whether you wear hearings or not, we encourage you to call and get more information.