> ...4) apparent pitch - I tend to agree with Petra on this one, that a "real" sound
> is not being heard, but something is being interpreted as "sound" by the sensory system.

My very limited experience with 'tones' causes me to agree with Petra. Would the suggested registry include other symptoms that might also be 'interpreted' by the sensory system? Example: I often feel tooth, jaw or gum pain a day or so before small (sometimes very small) earthquakes within 20 miles south or SE of this location. I can't identify the exact locations of those pains, and they jump around (left, right, upper and/or lower jaw). Dental checkups haven't shown a cause. I have reported those by email but usually not on a bulletin board and don't know if others nearby feel the same sensations.

How much interest could scientists have in a database of physical symptoms, including ear tones, that vary with individuals? Would proving consistent location and timing be enough incentive to search for an outside source that affects each human's sensory system differently?

Mary C.