Absolute pitch.

[Reinhart Frosch <reinifrosch@xxxxxxxxxx>]

The following observation may be partially related
to absolute pitch:
During choir rehearsals, the director sometimes
stops the singing and speaks for a few moments.
After that, most singers still can sing the tonic
of the interrupted song. In the brain of those
who do not possess absolute pitch, the
corresponding information appears to decay
with a typical half-life of a few minutes.

Reinhart Frosch
(r. Physics Dept., ETH Zurich).
reinifrosch@bluewin.ch