Setting bookmarks. Use the bookmarks options to define bookmark levels, create bookmarks from paragraph tags, and set up article threading. 1. In the PDF Setup dialog box, choose Bookmarks from the pop-up menu, or click the Bookmarks tab (Windows/UNIX). 2. Select Generate PDF Bookmarks.
Horizontal Pendular Nystagmus. 1  Lesions of the central tegmental tract (such as due to MS) 2  Spasmus Nutans (can also be vertical, torsional) 3  Nystagmus of the blind.  Congenital nystagmus.
Although the exact cause of nystagmus is not known, it is thought to be related to a disorder in the part of the brain that controls eye movement. Nystagmus may be present at birth (congenital nystagmus) and is often inherited or caused by development problems in the visual system. Another variation of nystagmus, called spasmus nutans, usually appears by the age of six months and goes away by itself in early childhood.