Scintillating Scotoma. (Migraine Scotoma). A scotoma is a âblind spotâ in front of the vision. The visual phenomenon of scintillating scotoma usually appears like a âtwinkling shadowâ or âzig zag patternâ before the eyes.While every experience is a little different, the most common symptoms are âblack spotâ or âtwinkling blurâ appearing before the eyes.he visual phenomenon of scintillating scotoma usually appears like a âtwinkling shadowâ or âzig zag patternâ before the eyes. While every experience is a little different, the most common symptoms are âblack spotâ or âtwinkling blurâ appearing before the eyes.
Cancel. Spiders live all over the world, including trees, dry areas, wet areas, under ground and in the oceans. Discover the different varieties of spiders on the earth with information from a science teacher in this free video on spider habitats.ancel. Spiders live all over the world, including trees, dry areas, wet areas, under ground and in the oceans. Discover the different varieties of spiders on the earth with information from a science teacher in this free video on spider habitats.
Spiders are abundant (over 1,000,000 individuals per acre in a grassy field) and can be found almost anywhere from the bedroom closet to the 22,000 foot level on Mt. Everest. There are about 2,500 different species in North America. Some live in holes in the ground while others may be found under rocks or logs.