Figure 3.

Visual information modulates activity of cells in the owl ICX when auditory and visual inputs are closely aligned in space. Cells in the owl ICX respond best to a sound from some fixed location L in space (determined by interaural timing and level cues) (dotted blue line; note that the location of the auditory stimulus does not change in this schematic) and that information is transmitted to the corresponding location within the OT (black arrow). When a visual cue occupies the same or some nearby location in space, gated feedback from the OT (red arrow) enhances auditory responses (solid purple arrow); visual cues at other locations will not enhance auditory responses (dotted purple arrows). The visual field corresponding to ≥50% of the max auditory modulation is defined as the visual modulation field (red field). Adapted from Gutfreund et al. (2002); and Bergan and Knudsen (2009).