Figure 1.

The ability of the auditory system to integrate spatial cues across frequency was tested in guinea pigs. A, Experimental setup schematic, extracellular recordings were made in primary AC and the IC of anesthetized guinea pigs. Pure tones of various frequency and level combinations were presented simultaneously to both ears via in-ear inserts. Color indicates the relative frequency used. B, Schematic neural trace. C, Stimulus design. The contralateral tone level was held constant while the ipsilateral tone level was varied. For each contralateral tone frequency (high or low), three different ipsilateral tone frequencies were presented at a number of levels, creating ILDs across different frequency ranges.