Re: How good is inter-aural frequency or pitch matching in normal humans?

Hi,

I have an anecdote, which might be interesting to you.

After I got my Msc in engineering physics, I went to sibelius academy to study music. I got a flu, and after it I had weird symptoms in my hearing related to pitch. With tone generator and monotic listening I noticed that the sick ear produced about semitone different pitch perception than the healthy ear. Playing piano or singing was really a torture then, I perceived sound very distorted, and heard additional tones when playing chords. I thought that the sickness caused my basilar membrane to be a bit thicker, producing these artifacts. This vanished in a week or so. I dont know if it vanished because of the inner ear got healthy, or if my brains got used to this situation.

Now, after about 20 years, I listened to few sinusoids around 1k monotically, and I have to say that my left ear produced somewhat different timbre, and perhaps also pitch. Left ear produces a bit brighter timbre, there is an audible distortion component in right ear.

-Ville

Dear List,

I have had a conversation with a musically keen retired physicist who assured me that when he holds up a tuning fork to one ear he hears the pitch of the tuning fork about a semitone lower than at the other ear. I had to say that I found that surprising. We always assume that there has to be a good alignment of frequency channels going into the binaural centers of the brainstem for example, and much effort is invested in trying to improve "inter-aural pitch matching" for cochlear implant patients. But I have to admit I know of no formal studies that have actually measured how good inter-aural pitch matching would be for normally hearing subjects, and whether a difference of a semitone (after all, only a few % in absolute terms) is absurdly large or within the expected human variability. Would any of you know of any papers that have looked at this?

Best,

Jan

--

Prof Jan Schnupp
University of Oxford
Dept. of Physiology, Anatomy and Genetics
Sherrington Building - Parks Road
Oxford OX1 3PT - UK
+44-1865-282012
http://jan.schnupp.net