Cognitive Neuroscience
There are two hemispheres in our brain, the right and the left. At first glimpse, these hemispheres appear to be mirror images of one another, however closer examination reveals that they are extremely specialized regions that serve differing functions. Left and right hemispheres are a vital part of the brain due to its function and roles. Both contribute mainly but have different roles the will be discuss in this paper. In general terms it is well understand that the left hemisphere controls linguistic awareness, such as talking, writing, reading, speech communication, spelling, verbal intelligence and memories, as well as information processing in the areas of math, grammar, typing, logic, analytic reasoning, and awareness of facts. On the other hand the right hemisphere is connected with unconscious awareness in the sense that it is not linguistically based, such as perception of faces and patterns, knowledge of body language and social cues, imagination and insight, instinctive reasoning, visual-spatial processing, and holistic understanding.
Communication among the two hemispheres takes place throughout the corpus callosum, which is more completely developed in women than men- likely giving rise to women’s intuition. In addition, this corpus callosum is the main connection between the left and right hemispheres of the cerebral cortex. Connection among the two halves takes place through axons that unite purely alike regions of the two cerebral cortices.
Furthermore, researchers found that, when presented with a stimulus, both hemispheres were active and could recognize the nature of visual stimuli in addition to spoken words. However, while the left hemisphere can express itself by verbally describing a stimulus, the right hemisphere can express itself non-verbally by selecting the matching stimulus. In addition, the left hemisphere deal with word choice, rules of grammar, and the meaning of words. The right hemisphere actually determines the emotional content of speech. It communicates using images and pictures and has extremely developed spatial abilities.
Moreover, brain damage might occur due to a wide range of conditions, illnesses or injuries. Probable causes of widespread brain damage include prolonged hypoxia (deficiency of oxygen), poisoning, infection and neurological illness. Frequent causes of focal or localized brain damage are physical trauma, head injury, stroke, aneurysm or neurological illness. The degree and effect of brain injury is frequently assessed by the use of neurological examination, brain imaging and neuropsychological assessment. In addition, there is a huge difference among adult and baby brains in what causes damage. Baby brains are particularly vulnerable to chemical damage. This is because the development requires chemical signals. Growing neurons can overcome mechanical damage. On the other hand adult brains are principally susceptible to cell death. This is because the moderately few new neurons are created in adults Axon growth is limited.
Moreover, damage or disease in the left hemisphere shows up in the right side of the body and visa versa. The left hemisphere tends to be foremost in terms of hand use and language storage in about 92% of humans. To determine its dominance simply watch which hand holds a pen and does more of the fine motor skills. The dominant side of the body as well tends to be larger than the non-dominant side. About 4% of humans have right hemisphere dominance and another 4% are in the middle with more or less symmetrical hemispheric function. As one would suppose, the split-brain patients have disjointed cognitive functions for the reason that their hemispheres could not share information. In unnatural experiments, information could be supplied to merely one hemisphere and would not be obtainable to the other. Each hemisphere revealed a separate consciousness in terms of responses to stimuli and reportable contents. Typically, only the left hemisphere could speak and could only report on information received on the left. The right hemisphere could not talk, however communicated with nonverbal vocalizations and in other ways.
Furthermore, the physical, behavioral, or mental changes that might result from head trauma depend on the areas of the brain that are injured. Most injuries cause focal brain damage, damage confined to a small area of the brain. The focal damage is most often at the point where the head hits an object or where an object, such as a bullet, enters the brain. In addition to focal damage, closed head injuries often cause diffuse brain injuries or damage to numerous other areas of the brain. The diffuse damage occurs when the impact of the injury cause the brain to move back and forth against the inside of the bony skull. The frontal and temporal lobes of the brain, the major speech and language areas, frequently receive the most damage in this way for the reason that they sit in pockets of the skull that allow more room for the brain to shift and maintain injury. Because these major speech and language areas frequently obtain damage, communication difficulties commonly occur following closed head injuries. Other problems might include voice, swallowing, walking, balance, and coordination difficulties, also as changes in the capability to smell and in memory and cognitive (or thinking) skills.
The effects of the brain damage are usually greatest immediately following the damage. Nevertheless, several effects from traumatic brain injury might be misleading. The newly injured brain frequently suffers momentary damage from swelling and a form of “bruising” called contusions. These types of damage are typically not permanent and the functions of those areas of the brain return once the swelling or bruising goes away. Consequently, it is hard to foresee precisely the extent of long-term problems in the first weeks following traumatic brain injury. In addition, focal damage, nevertheless, might result in long-term, lasting difficulties. Improvements can occur as other areas of the brain learn to take over the function of the damaged areas. Children’s brains are much more able of this flexibility than are the brains of adults. Therefore, children who suffer brain trauma may progress better than adults with similar damage. Focal damage which is frequent during motor vehicle accident may result in both coup and countercoup injuries.
Coup injuries happen at the direct site of impact while countercoup is the opposite site of injury.
People with right hemisphere damage speak with less modulation and expression; also they frequently have trouble interpreting the emotions that other people express through their tone of voice. Moreover, the left hemisphere is more focused on details and the right hemisphere is better at perceiving in general patterns.
References:
Brain Facts, Retrieved on February 23, 2006 at http://www.brainconnection.com/library/?main=explorehome/brain-facts
Kalat, J. W (1998) Biological psychology. Pacific Grove, CA, Brooks/Cole.
