Figure 1.

The apparatuses used for visual field assessment and multisensory training. (Left) A schematic of the perimetry device used to screen animals for their suitability for behavioral training. Fixation was induced by food presented through the hole at the center of the front wall, and visual orientation and approach were initiated by a ping-pong ball (on a metal wand) thrust into the visual field from behind an opaque curtain. (Right) A schematic of the perimetry device used for rehabilitative training and quantitative assessment of visual function. LEDs (red) and speakers (gray) were arranged along the horizontal axis and separated by 15°. The device was housed in a lighted room but shielded from direct overhead lighting by a flat ceiling. The animal was trained to fixate on the central LED at 0° before each trial (only the most central (i.e., nasal) LED in each 3-LED display was used as a visual target). Trials consisted of V alone or a crossmodal (A-V) combination. The animal’s task was to orient to and approach the location of V whether presented alone or in combination with A.