Amsler grid Amsler grid The Amsler grid, used since 1945, is a grid of horizontal and vertical lines used to monitor a person's central visual field. The grid was developed by Marc Amsler, a Swiss ophthalmologist. It is a diagnostic tool that aids in the detection of visual disturbances caused by changes in the retina, particularly the macula (e.g. macular degeneration, Epiretinal membrane), as well as the optic nerve and the visual pathway to the brain. In the test, the person looks with each eye separately at the small dot in the center of the grid. Patients with macular disease may see
Body part as an object tool-use knowledge is physical, meaning that it involves the actual manipulation of an object. The other type of knowledge is conceptual: using the physical (or active) knowledge of tool-use to add to the mental representation of the tool. Action schemas explain how we develop motor skills and performance of many complex motor-activities. Essentially, the more an object is manipulated and used, a greater schema is developed in the brain. Therefore, increased object use gives us a greater understanding of the object, which then facilitates our understanding of the object independent of its context. The strength of an action schema is