[Voluntary changes of visual evoked potentials in cases with hysteria and/or simulation]. / Alteración voluntaria de los potenciales evocados visuales (VEP) en casos de histeria y/o simulación.

We report a 25-year-old woman with gradual loss of visual acuteness, during puerperium and blindness in fifteen days. Two months latter she remain steady. Visual evoked potentials using monocular checkerboard pattern-reversal, were abnormal. Clinical suspicion of voluntary alteration of VEP was considered. A second VEP exploration with binocular stimulation and maneuvers of distraction were carried out. Normal VEP were recorded. Deliberate alteration of the visual evoked potential should be considered in patients suspicious of hysteria or malingering.