Fig. 14.

Set of hemifield polar plots of the response to a single pulse (unpaired sound epoch) as a function of azimuth for four different sound levels (A). Activity plotted is to a single-sound broadcast at a rate of 2 Hz through each speaker at four different sound levels (84, 74, 64, and 54 dB SPL). Note the azimuthal position evoking the maximum response shifts from the periphery to a more central location as the sound level is attenuated. B, Set of hemifield polar plots of the azimuthal response profile to single-sound elements and to the paired echo at BD (4 msec) of the fixed-delay epoch. The response to the single P (unpaired sound epoch) at the same sound level as the paired echo (64 dB SPL) is also shown (bottom right plot). Note that the magnitude of the responses to unpaired stimuli is significantly less than the response to the paired echo, even at the same level of acoustic stimulation.i, Ipsilateral auditory space; c, contralateral auditory space.