Quantitative evaluation of azimuth and elevation limits of the visual field representation.

<p>An example of the thresholded activity map of azimuth and elevation limits (A-D), its corresponding iso-azimuth and-elevation lines (E-H) and their overlay is shown (I-L). <b>A, E and I</b> shows thresholded activity map, iso-azimuth lines and their corresponding superimposition, when the monitor was positioned at 0° with respect to the eye of the bird. The iso-azimuth lines span from -5° in the ipsilateral visual field to 35° in the contralateral visual field, thus demonstrating the frontal azimuth limit of the visual field represented in the visual wulst. In the same way, <b>B, F and J</b> shows the thresholded activity map, iso-azimuth lines and their corresponding superimposition, when the monitor was positioned at 90° with respect to the eye of the bird. The iso-azimuth lines spans from 55° to 125° in the contralateral visual field, demonstrating the lateral azimuth limit of the visual field represented in the visual wulst. <b>C, G and K</b> demonstrates the lower elevation limit which is -10° below the horizon. <b>D, H and L</b> shows the upper elevation limit which is +25° above the horizon.