 The so-called Flynn phenomena consists of paradoxical constriction of the pupils to darkness. Look at the normal pupil response. Lights turned off, the pupils dilate. We'll show you some examples of paradoxical constriction of the pupils. This phenomena is observed in many congenital retinal disorders including achromatathia, congenital stationary night blindness, Lieber's congenital amarylosis. Lights off, look at the constriction. These are even seen in some of the optic nerve disorders, occasionally for example in dominant optic atrophy. Keep watching and you'll see that this is a fairly dramatic response. Although it's easy to observe here at the infrared pupilometer, you can observe it at the chair side as well by turning the lights on and off and shining a light obliquely in the eyes. I think that this sign is important to try and seek when you're confronted with a patient with either congenital poor vision or slowly progressive bilaterally poor vision. When you see it, it should suggest a problem in the retina.