At which part of the eye are focused images most accurately conveyed to the brain?
cornea
retina
optic nerve
macula

Images are focused most accurately conveyed to the brain at the macula.

Explanation:

The macula lutea is an area at the back of the retina where there are mostly cones in the light-sensitive layer. Cones are the sensory cells with which it is possible to perceive colors.

The macula lutea - as the focal point of the eye lens - is the area with which one can see the smallest details. The visual acuity is greatest in the middle of it - the fovea centralis: the point almost right behind the eye lens - an area of only one square millimeter in area. However, the cones only function if it is not too dark.  

depends on what they need

answer; the parasympathetic nervous system;