(AGL) Chairman, Department of Ophthalmology, The Methodist Hospital, Houston, Texas; Professor of Ophthalmology, Weill Cornell Medicine, New York City, New York; (SW) Class of 2022, Baylor College of Medicine, Houston, Texas
Subject
Akinetopsia; Motion Blindness
Description
Summary: • Akinetopsia: disorder in which the patient cannot perceive motion o Also known as motion blindness • Symptoms: o Patients report seeing objects in slowed down motion, like stop-action motion o May report seeing individual frames of an object moving o Objects may appear to disappear and reappear randomly • Pathophysiology: o Result of damage to the V5 visual association cortex in the medial temporal (MT) region o Visual information is first received in the V1-2 visual association cortex, and the visuospatial motion is then processed in the V5 (MT) area.
Transcript
So we are going to talk about a very strange complaint called akinetopsia. "Opsia" - see. "Kine" - move. "A" - not. So it doesn't seem to be moving. It is a little bit of a misnomer, because usually it is not completely stopped, but its slowed down like frames in a movie reel. And, this akinetopsia is one of those crazy sounding complaints that is absolutely real. So patients with the motion blindness, akinetopsia, have a very specific way of describing their complaint. They see things in stop action motion. So if they are watching a person moving, they might see the individual frames. Or it might just appear to them that the person disappears or reappears randomly to them. It is a very specific place that this akinetopsia comes from, which is the vision center association cortex 5 in the medial temporal region, which is in charge of visual-spatial motion. So, after the information is received in the visual association cortex, we are going to be processing that information and this happens to be the medial temporal V5 region. So a lesion in this region produces a very specific complaint - motion blindness, also known as akinetopsia.
