S. Boatright-Horowitz
Andrea Megala Simmons
Dept. of Psychol., Brown University, Providence, RI 02912
The American bullfrog (Rana catesbeiana) provides an excellent model for neuroethological studies in pitch perception. It is particularly useful in the development of an auditory model of temporal coding because of its sensitivity to periodicities in complex sounds. Using a dorsal surgical approach, recordings were made of the neural synchronization responses of 8th cranial nerve fibers to AM tones and AM noise in the frequency range of 200 to 2500 Hz at different modulation depths, followed by single- and multi-unit recording in the midbrain (torus semicircularis) to the same stimuli. Analysis of synchronization rates of peripheral and central auditory sites elucidates the differences in neural temporal representation of the waveform periodicity for subjects ranging from recently post-metamorphic froglets to fully mature adults.