There's nothing uncommon in that.

You have its most familiar form in the sensitivity of the blind.

You've watched the same thing at work in certain forms of hypnotic experimentation, haven't you?
"Through the operation of entirely understandable causes the mind gains the power to react to vibrations that normally pass unperceived; is able to project itself through this keying up of perception into a wider area of consciousness than the normal.

Just as in certain diseases of the ear the sufferer, though deaf to sounds within the average range of hearing, is fully aware of sound vibrations far above and far below those the healthy ear registers." "I know," he said.

"I don't need to be convinced.