The Human Brain, Left Hemisphere

I was talking with a friend the other day and the topic of brain hemispheres came up. My friends contention was that the information about how the brain hemispheres work, as far as which side controls what, isn’t always the way it’s stated in the text books, manuals and research papers. That’s true, nothing’s always the way it seems and besides, what’s normal? Some people have the heart, spleen, liver and other major organs on the opposite side as what’s considered normal.

The objective of the information in past and future anatomy articles is about generalizations. My intent is not to address specifics. The objective is to provide information and education.

The left brain hemisphere, or logic brain, acts as a feature combiner and comprehends spoken language by performing phonetic analysis of the sounds, as opposed to the right brain method of comprehending language by matching acoustic sound patterns. The left brain has the ability to extract isolated details from spoken words or sentences, can generate correct spelling from scratch and can learn from reading by reading for meaning even if the topic is dull. Where the right brain lacks the short-term memory capabilities to be able to follow long sentences and extract their meanings, the left hemisphere can. If a sentence is long and complex grammatically, it falls into the realm of the left hemisphere for comprehension and de-coding for meaning.

The left hemisphere is able to work with both slow and rapid speech where the right brain can only deal effectively with slow speech. Complex syntax, semantics, phonics, sight words, new vocabulary (read or heard) are all shuttled to the left brain for comprehension. The left brain is also where re-worded sentences or explanations, even if redundant, are processed. The information processing that one hemisphere isn’t capable of processing is switched to the other via the corpus callosum.

The left hemisphere’s speaking and listening vocabulary is almost as large as that for reading and sight and allows it to be able to equally extract meaning from written or spoken words. When we read and hear the words in our head, they’re formed (sub-vocalized) in the left brain because it, and not the right hemisphere, has the ability to de-code written words acoustically.

The left brain doesn’t have the ability to handle ambiguity (needs absolutes, clear cut patterns and predictability), doesn’t handle receiving input from changing sources, doesn’t do well if required to make changes in solution strategies or changes in timing of responses.

Left is the logical and analytical side and processes information in a sequential manner. It works best with life and projects when they’re presented in a planned and structured manner. It’s the side that works best with multiple choice questions, prefers authority structuring, controls feelings, is future oriented and time conscious, sees distinct right or wrong according to the prevailing cultural/beliefs system and discerns sharp perceptual and conceptual boundaries. This makes the left brain more involved in seeing differences when dealing with others who are felt to be of lower caste or intelligence.

Even though the left brain prefers talking and writing it’s also the hemisphere that’s more likely to suspect everyone and alienate friends. Those who are left brain dominant are more likely to buy, buy, buy, test the limits of credit cards (and their ability to pay) clean everything, buy everything and stock up for suspected or unknown eventualities, reorganize shelves, cupboards, retrace their steps and reorganize shelves, etc. perpetually. They’re also more likely to quit their job before being fired.

If we go back and review the information on all aspects of the brain it’s easy to see why we have differences and difficulties. Fortunately, few of us are totally dominated by one hemisphere or the other. If that were the case it would be a world of, “In this corner are the right brainers and in this corner the lefties. Prepare your agendas and come out fighting.” Which, by the way, is how we seem to handle most difficult problems anyway.

All of us are endowed with two sides of the brain and a way for the information to travel from one hemisphere to the other. The brain is the area that heredity can be the largest or smallest factor in the way we interpret life around us. If we don’t like our life and our health, the brain gives us the means with which to change. The choices are also up to one of the brain’s functions but the mind and the brain aren’t the same.

Copyright 2007 Larry R. Miller