I had an very interesting chat session with people working as volunteers in Dialogue In the Dark Tokyo for a book project. These are visually challenged people. "Taicho" ("The Boss"), "Mikitty", and "Hiyamacchi" ("The mountain guy") were there.
When the chat was close to the end, I accidentally dropped a coin on the Chinese restaurant floor in which we were meeting. "100 yen!" exclaimed The Boss, without moving a muscle of his characteristically cool face.
"Correct!" I cried. "Do you mean you can tell the coins just by listening?"
"Yes, naturally." Mikitty said in her warm voice. The Mountain Man chuckled, nodding.
Getting very interested, I said "let's try", and they said "why not?"
I dropped the 1 yen, 5 yen, 10 yen, 50 yen, 100 yen, and 500 yen coins. Each time, they could tell which very accurately. I was impressed.
"The 50 yen and 100 yen coins are a bit tricky to tell apart", The Boss explained. "The 1 yen and 10 yen are the easiest."
What was impressive was the immediacy with which the replies came. Evidently they have been practicing and exercising the coin telling game all the time, all along. The rest of us, on the other hand, have been relying on the visual information to tell the coins we dropped, so that the particular neural function to decipher the sound of collision never developed to any substantial degree.
For me, it was yet another testimony of the richness of the diversity of ways that brains can develop, given various constraints and encouragements.
With that marvelous finishing fanfare of coins hitting the floor, we parted. I shook hands with The Mountain Man, Mikitty, and finally The Boss, and said good byes.
The Boss, who is a musician, had a really tight grip. The firmness and warmth was the coda of the evening music.