prenatal auditory localization

[Richard Parncutt <richard.parncutt@xxxxxxxxxxx>]

Newborn infants can localize sound (at least left-right), and show it by
turning their head (Morongiello, JASA 1989). The question arises as to
whether they are using intensity or phase cues, and whether the ability
is somehow innate or already practiced before birth. From the point of
view of physics, intensity and phase cues should be available (if
somewhat impoverished) before birth, at least in the frequency range in
which sounds are audible to the fetus (say, 100-1000 Hz).

Does anyone know of experiments to investigate the possibility of fetal
sound localization? It might be as easy as studying lots of ultrasound
photos. Friendly gynecologists tend to chat to their expectant clients
while making ultrasound photos. According to the literature on prenatal
hearing, the sound of their voice should be audible to the fetus,
although not as loud as the mother's voice. If the fetus can localize,
it may turn either toward or away from the gynecologist. To find out if
that is that case, one could for example find out whether the
gynecologist was on the left or right side of the mother while making
the ultrasound photos, and then compare that information with photos in
which the orientation of the fetus is clear. Has anyone done anything
like that?

--
Richard Parncutt, Ph.D., Professor of Systematic Musicology
Department of Musicology, University of Graz
Mozartgasse 3,  A-8010 Graz (Austria/Europe)
Tel +43 316 380-2409 or -2405   Fax +43 316 380-9755
<lastname>@uni-graz.at   http://www-gewi.uni-graz.at/muwi/parncutt