Invisibility of moving objects: a core symptom of motion blindness.

Although the higher brain mechanisms of seeing moving objects have been deeply investigated, motion blindness remains a rare and enigmatic symptom. Very few case reports well describe the detailed symptoms and the lesions. We report a case of a patient who presented with invisibility of moving objects, that is, motion blindness resulting from a unilateral right hemispheric lesion. This man, in his 60s, suffered persistent motion blindness from a unilateral right temporoparietal subcortical haemorrhage. He could not see the moving objects, just felt the objects 'disapper' when they began moving. The symptom was observed not only in his daily life but also during investigations in the hospital. To the best of our knowledge, this is the first report of a patient who showed persistent motion blindness with a right unilateral lesion, and only the second one with clinically apparent motion blindness, whose symptoms were similar to those of the first reported case.