Introduction

In this activity, you will simulate what it is like to have a scotoma in your central vision due to age-related macular degeneration (AMD). First, let’s break down the components of AMD and think about what each part of the term means. The “age-related” part of the name indicates that this disease usually occurs in older adults, starting at age 50 and becomes more prevalent with age. The “macular” in AMD refers to the central part of your retina, the macula, that contains the fovea and a high concentration of cones. It is this part of the eye that is affected by AMD, leading to a loss of central vision. The “degeneration” part of AMD can occur in either a “wet” or “dry” form. The wet form causes vision loss due to abnormal blood vessel growth (and possible leakage) below the macula, while the dry form causes vision loss via atrophy of the pigment epithelial layer below the retina, leading to degeneration of the rods and cones above it.

Once photoreceptors die off in the fovea, it is impossible to regrow them. This results in a loss of central vision–a blank spot in the visual field–called a scotoma.

To experience a bit of what it is like to have a central field scotoma, stare at the center of the circle on the left. While keeping your eyes fixated in the center, move the circle around and try to guess which president is being pictured. If you find that you want to peak at the edge of the circle where the scotoma is absent, then you are starting to realize how important your central vision is!

Instructions

Use your mouse (click-hold-drag) to move the simulated scotoma in relation to the image.