I had a wonderful discussion with one of our blog readers about how Lily might hear the different notes on the piano. I'm appreciative of her expert explanation and feedback.
Lily, depending on where you play the notes on the keyboard, may be able to tell the difference of 1-4 semitones. In some areas, she’ll be able to tell you that C-C# sound different (when not looking) but may not always be able to tell you which direction they are going. In other areas of the keyboard, she may have to have C-E or larger to tell a difference. In addition, most implants are programmed for speech at around 250Hz, which is the F# below middle C. This usually knocks out the rest of the notes below there, but not always. Her larger challenge would be telling major from minor chords (and honestly, as a trained musician, it can be challenging).
Regarding music you have ‘The Good, The Bad and the Ugly.’ The good is rhythm, the bad is timbre and the ugly is pitch. Mainly that is because rhythm is a significant part of speech and helps us so it’s conveyed very well. Timbre, the ability to detect different tone qualities is harder, but can be learned. It is hard because of its complex spectral quality. Think about how similar a clarinet and saxophone sound, for instance, now add in the complexity of a cochlear implant’s processing strategy. Finally,pitch is the hardest, simply because you and I have 30,000 hair cells (each of which responds to one frequency) and Lily now has 18 electrodes to represent those same 30,000 hairs cells. That’s not to say she won’t be amazing (she clearly already is), but that she may have a “sweet spot” for certain types of music perception and production (ie., singing on key in a specific range).
Then Lily's fabulous music teacher, who shows so much interest in this topic (thank you), told us the following:
Semitone is another word for a half step, which would be the difference between one note next to another one on the piano, like B-C, E-F, or B flat-B. Lily was able to sing descending Major triads starting on Eb (E flat) and ending on G below middle C (which is pretty low for a kindergartner) So she sang descending triads in the Major keys of Eb, D, Db, C, B, Bb, A, Ab, and G. I'm convinced she can hear the difference between 1 semitone.