Dominance is a huge determining factor in the brain's ability to store and retrieve information.  In order to be neurologically efficient (like a defragged computer), your brain must be neurologically organized - one hemisphere must dominate and coordinate your entire body.  The determination for dominance starts with the hand.

Hand dominance is genetically predetermined and should not be encouraged one way or the other.  It should emerge by the time a child is 3 to 8 years of age. If an individual is right handed it is much more efficient for the right ear, eye, and foot to be dominant as well.  If left handed it is best to be completely dominant on the left side. To be right eared or eyed does not mean that you have better hearing or vision in your right; it means that your right directs which hemisphere of the brain information is stored.  

    Reasoning, analytical and logical thinking are the job of the dominant hemisphere of the brain and when neurologically organized (dominant all on one side) you have much more access to these vital skills. Thus, when you go to retrieve information, it is easily accessible.  If you are mixed dominant, your sub-dominant ear or eye will file information in your sub-dominant hemisphere, which is where music, creativity and emotion take place.  Information stored here is much more difficult to retrieve.

     Individuals with mixed dominance are typically more emotional, easily upset and hard to calm down.  When they are under stress or pressure they often do not have access to information they know.  These are the children that do not test well or baffle the parent because they know something perfectly one day, but the next day, they don't recall ever being presented with the information.  This can be extremely frustrating for both parent and child!  When a child is frustrated day after day, you will have a child with low self-esteem, long-term memory problems, and often emotional and behavior problems as well.  This happens because they are functioning using the sub-dominant (emotional) hemisphere of the brain.   

     Symptoms of mixed dominance include:  long-term memory problems, inability to stay on task, reading difficulties, number and letter reversals, emotionality, spelling difficulties, obsessive-compulsive behaviors, poor testing ability, and inability to retain information.

            For information about testing for dominance and what to do if your child is mixed dominant, read the following article:   Learning Disabilities