Some of the mechanical visual skills which are related to reading include focusing or accommodation, and eye teaming, or convergence. Fatigue of one or both of these systems may interfere with reading. There is also a relationship between eye movements such as saccades (whereby we change fixation from one target to the next) and smooth following movements known as pursuits and reading. Children who cannot make accurate eye movements are often found to skip lines and words while reading.
The visual system was originally designed so that the peripheral vision was responsive to motion detection (danger from the jungles) with a central portion for fine discrimination (to identify the source of danger; e.g., a lion.) In the school environment the child is expected to ignore the peripheral portion of their visual system and pay attention with the central portion. If the child can not ignore the peripheral portion, he/she becomes distracted. Improvement in eye movement skills often results in less distraction and fewer errors of skipping words while reading.