Date posted: 28th February 2017 / Resources
Literature Works’ intern, Bernard Masters (PhD) writes on the relationship between reading and eye movements.
The muscles of our two eyes must work together. The muscles on the outer side of the right eye must be balanced by the inner eye muscles of the left eye if we are to follow a line of writing. The controls of the mechanisms that allow us to read are based on our primitive mechanisms that allow the eyes focus on one object that is travelling with a number of similar objects.
When the group of objects move to the right, the left brain follows the group. The left brain also controls the side of the body and in particular the right arm. Ninety percent of people are right handed, (and under the control of the left brain), it is easier for us to read from the left to the right. Also the dominant language centre is in the left brain.
Example of the controls.
The left brain sends a signal to the right arm to do some work and grasp an object. This signal is called feed-forward. Having sent the message to the arm, the brain must get a response from that arm, this is the feedback signal. However, having sent the signal and received confirmation that it has reached the arm successfully, the object may have moved, or that the eye-brain mechanism has misinterpreted the distance, size or weight of the object.
It is all very well giving out orders and receiving acknowledgement of an appropriate action, the question arises is the order suitable, or has the situation changed. This is when the Doing Brain (cerebellum) modifies and amends the signal. The Doing Brian now copies the signal and modifies the action to make it appropriate for the now situation. This is called Efferent Copy. We have all been given directions that appear appropriate at the time, but when it comes to carry out the orders, we have to modify, increase or decrease and sometime abandon the directive.
Returning to the left brain/right hand actions, in the beginning, the Doing Brain does not have so much as a programme of actions. When we go to lift something and we think it is light in weight when in actual fact it is heavy, we are initially fooled and have to adjust our muscle co-ordination. Once learned, we can lift the object easily without having to judge the weight. The Doing Brain is like the personal assistant to the chief executive. The assistant can guess, how, when where, why and what the boss could do. The personal assistant can now plan for any eventuality because a number of options have been tried and tested.
However, if the personal assistant is overloaded with work, fatigue can occur and the timing of reactions to the boss’ plans may be too late, or too early.
The controls of the eye movements when tracking a line of text are similar to the action abilities by the Thinking Brain/Doing Brain/arm performance.
In an ideal situation, the eyes should move from one word smoothly on to the next and then return to the left hand edge of the page to start a new line of text.
Tracking the words, best situation: The eyes follow a line of print in smooth little jumps from the beginning to the end of the line.
Poor tracking of the words suggests that the doing brain is fatiguing. The eyes over and under correct and sweep the page. The two eyes are not co-operating.
This is type of eye movement may be seen in people with reading problems. Simple solutions include, asking the reader to cover one eye and read. Another is to cut a slot in a piece of paper and cover the words so that only one word is shown. This may help to retrain the doing brain. Another is to ask the person to juggle tennis balls, starting with one, and adding another. This will help with eye motor skills.