Auditory Neuroscience 1 Spatial Hearing. Systems Biology Doctoral Training Program Physiology course Prof. Jan Schnupp [email protected] HowYourBrainWorks.net. Hearing: an impossible task!. http://auditoryneuroscience.com/foxInSnow. ITD. Interaural Time Difference (ITD) Cues.
Unlike ITDs, ILDs are highly frequency dependent. At higher sound frequencies ILDs tend to become larger, more complex, and hence potentially more informative.
ILD at 700 Hz
ILD at 11000 Hz
Hofman et al. made human volunteers localize sounds in the dark, then introduced plastic molds to change the shape of the concha. This disrupted spectral cues and led to poor localization, particularly in elevation.
Over a prolonged period of wearing the molds, (up to 3 weeks) localization accuracy improved.
ITD tuning varies with sound frequency: no map?
CN, cochlear nuclei;
SOC, superior olivary complex; NLL, nuclei of the lateral lemniscus; IC, inferior colliculus; MGB, medial geniculate body.
Jenkins & Merzenich, J. Neurophysiol, 1984
r(t) = i1(t-1) w1(1) + i1(t-2) w1(2)+ ...+ i2(t-1) w2(1) + i2(t-2) w2(2)+ ...
+ i3(t-1) w3(1) + i2(t-2) w3(2)+ ...
Left and Right Ear Frequency-Time Response Fields
Virtual Acoustic Space Stimuli
Schnupp et al Nature 2001