|MadSci Network: Neuroscience|
The mentioned article, seems to be mainly focused on proving that common instruments (cymbals) and specialized techniques (muted trumpet) can produce sound well above 20 kHz. As background, 20 kHz is the widely accepted upper limit of human hearing by air conducted sounds. In their discussion they refer to a 1991 article in Science which found that via bone conduction, ultrasonic stimuli can be perceived up to 30+ kHz. In a response, Dobie and Wiederhold argue that this phenomenon may simply be demomdulation of the ultrasonic stimuli into the traditionally audible range.
Since then several studies have attempted to prove where this "ultrasonic hearing" is coming from. Some evidence suggests that it is produced by inner hair cells in the cochlea, but several hearing researchers still feel it represents sacular activity.
In summary, yes we can perceive frequencies above 20 kHz if they are loud enough to be conducted by bone. Practically, if overtones at these ultrasonic frequencies are present, there is almost always a MUCH louder fundamental in the traditional range of hearing that will dominate the perceived pitch.
Try the links in the MadSci Library for more information on Neuroscience.