[Detection of central perceptual decrement in optic neuropathies with computer perimetry (Octopus) and visual evoked potentials].

Contrast sensitivity, as far as tested with pattern-VEPs, and light-difference sensitivity, psychophysically tested with the Octopus in the visual field center, seem to reflect different visual functions, because they are disturbed to a different degree in discrete neuropathies: light-difference sensitivity may be within normal range and a careful numerical analysis is needed in order to find pathologic differences. With VEPs, on the other hand, it is easier to detect a loss of normal neural conduction.