Subject: Re: [AUDITORY] Localizing smoke detectors - why is it so hard? From: Stephanie Bertet <s.bertet@xxxxxxxx> Date: Tue, 25 Jun 2013 12:04:13 +0100 List-Archive:<http://lists.mcgill.ca/scripts/wa.exe?LIST=AUDITORY>
Are you talking in anechoic conditions? The room might play a large role on the perception of the position. Stephanie On 25 Jun 2013, at 10:40, Leslie Smith <l.s.smith@xxxxxxxx> wrote: > I wonder if the fact that it's above your head makes a difference - peopl= e are generally better at localisation in azimuth horizontally than at alti= tude=85 >=20 > --Leslie Smith >=20 > On 25 Jun 2013, at 09:46, Jennifer M. Groh wrote: >=20 >> Dear List, >>=20 >> I am writing a book for a general audience on how the brain processes sp= atial information ("Making Space"). The chapter on hearing covers many topi= cs in sound localization, but there is one that I'm currently still quite p= uzzled about: why it is so hard to localize a smoke detector when its batte= ry starts to fail? Here is what I have considered so far: >>=20 >> - To my ear, the chirp sounds high frequency enough that ILD cues should= be reasonably large. >>=20 >> - At the same time, it seems to have a broad enough bandwidth, and in an= y case it has onset-and-offset cues, that ITD cues should be usable. >>=20 >> - A possibility is that the chirp is too brief, and that limits dynamic = feedback, i.e. changes in ITD and ILD as the head turns during a sound. H= owever, in my laboratory we have obtained excellent sound localization perf= ormance in head-restrained monkeys and human subjects localizing sounds tha= t are briefer than the reaction time to make an orienting movement. >>=20 >> - An additional possibility is that we have too little experience with s= uch sounds to have assembled a mental template of the spectrum at the sourc= e, so that spectral cues are of less use than is normally the case. >>=20 >> I'm leaning towards a combination of the last two factors, which togethe= r would render the cone of confusion unresolved for these stimuli. >>=20 >> Thoughts? >>=20 >> Best wishes, >>=20 >> --Jennifer Groh >>=20 >> --=20 >> Jennifer M. Groh, Ph.D. >>=20 >> Professor >> Department of Psychology and Neuroscience >> Department of Neurobiology >> Center for Cognitive Neuroscience >>=20 >>=20 >> B203 LSRC, Box 90999 >> Durham, NC 27708 >>=20 >> 919-681-6536 >> www.duke.edu/~jmgroh >=20 > Professor Leslie S. Smith B.Sc. Ph.D. SMIEEE, > Head, Institute of Computing Science and Mathematics, School of Natural S= ciences > University of Stirling, > Stirling FK9 4LA, Scotland > l.s.smith@xxxxxxxx =20 > Tel (44) 1786 467435 Fax (44) 1786 464551 > www http://www.cs.stir.ac.uk/~lss/ >=20 >=20 >=20 >=20 >=20 >=20 >=20 > --=20 > The University of Stirling is ranked in the top 50 in the world in The Ti= mes Higher Education 100 Under 50 table, which ranks the world's best 100 u= niversities under 50 years old. > The University of Stirling is a charity registered in Scotland,=20 > number SC 011159.