There may, however, be certain medical conditions that could limit one's prospects for speed reading. These include, but are not limited to Dyslexia, which alters the way the text looks, and certain mental health problems, such as depression, which could interfere with the ability of the student to sustain a regular consistent practice of the speed reading principles to perfection over the short term of a speed reading course. But even some readers with Dylexia may be able to practice and to apply the principles of speed reading perhaps over a longer developmental reading time. There is always hope where there is interest and determination. Most people think that you have to be a rocket scientist in order to be a speed reader.
Eye speed is the key to being a speed reader.
Some Dyslexic readers may be able to gain benefit from speed reading principles over a longer reading developmental time. Readers with Attention Deficit Disorder experience difficulties with speed reading. Schizophrenics sometimes make excellent super readers.