In physiology, the brain and nervous system is an intricate part of an organism that coordinates all of its functions and sensory data by sending messages to and from various parts of the body. The major parts of the brain are The Central Nervous System or CNS, which controls the majority of motor function; The Sensory System or SSS, which controls vision, hearing, touch, and other basic sensory functions; The Motor System or MSM, which controls movement and co-ordination; The Central Cerebral Cortex (CC) which is important in thought and memory; The Urinary Nervous System (UNS) which monitors organ functions; The Central Sensory Memory (SML) which is concerned with visual, hearing, emotional, and cognitive processes; and The Behavioral Processes (BPH) which is an important part of the stress response. In animal research, the brains of carnivores, pigs, and other animals are studied in great detail to discover the basics of how they think, how they feel, and how their behaviors affect others and their environments.
Recent years have witnessed tremendous advancements in the understanding and even the exact mechanisms of how the brain and nervous system function and cause disease. One of the most exciting areas of recent study and research is neuroplasticity or learning. This study has found that the brain can change its plasticity and capabilities in response to external stimuli, allowing for extraordinary flexibility and relevancy. Neurons in the brain can grow and expand, forming new memories and behaviors in response to the experience of the surrounding world, allowing humans to learn nearly every ability imaginable.
Neuroplasticity is caused by changes in the concentration and levels of neurotransmitters produced by the brain and nervous system. These neurotransmitters regulate multiple areas of the nervous system and allow nerve cells to communicate with each other in a number of ways. For example, one neurotransmitter is responsible for communication between the spinal cord and brain. Another controls the movement of muscles. Yet another controls the timing of nerve impulses, allowing them to travel from nerve cell to nerve cell.
The level and strength of these chemicals are controlled by the regulation of a number of proteins and receptors in the brain and nervous system. In essence, these proteins and receptors control how much the brain can respond to external stimuli, which in turn determines how well the brain and nervous system can adapt. As the brain and nervous system change their plasticity through environmental and physical stressors, it needs to be able to replace those changes with new ones. Neurons in the spinal cord and brain continue to grow and expand in response to these changes, creating new memories and behaviors as well as responding to the surrounding environment.
When an individual experiences some type of trauma to either the brain or nervous system, it causes irreparable damage to the cells and fibers of the brain and nervous system, sometimes resulting in death. However, even mild injuries to the brain and nervous system can result in a variety of lifelong disabilities and illnesses. In fact, even a single blow to the head can result in devastating effects, sometimes resulting in death. Fortunately, individuals who suffer this type of injury can experience a full recovery if they receive immediate medical attention after the incident. In some cases, victims may remain awake and alert far beyond the normal limits of waking consciousness, with a full understanding of their surroundings and a full ability to move around and perform everyday functions.
However, as most traumatic brain injuries and illnesses do not have symptoms that are readily apparent, until later in life, victims may struggle with a range of cognitive and emotional symptoms that are similar to those of stroke or brain cancer, but without pain or discomfort. These symptoms can include poor concentration, memory loss, impaired judgment, and problem-solving skills, and changes in emotional and behavioral patterns. It has been found that the majority of these symptoms are directly related to a loss of function in the central nervous system (CNS) or the temporal lobe. Other symptoms can also be noted such as speech problems, decreased ability to read and write, problems with processing speed and in hearing as well as abnormalities in speech production.
The Temporal lobe is involved in our cognitive abilities and is the part of the brain responsible for coordinating and integrating information from visual, auditory, and tactile sources. If a victim of TBI loses function in any of the five senses as well as any control over the body parts that were used for functioning, then the fault is true with the frontal lobe. In order to see a clear example of how these types of losses impact the overall functioning of the body, simply take the time to look at the following figure.
This figure, which depicts the distribution of nerves throughout the body, clearly shows a major loss of sensory integration in cases of TBI. While you are looking at this figure, notice that there are very few nerves coming from the scalp down to the toes, even though there are plenty of nerves connecting the head to the chest, neck, arms, and legs. If the accident did not involve injury to the head and the spinal cord, there should have been many more nerves from the scalp leading to the various body parts. When looking at the distribution of sensory fibers, it is important to remember that it is not the actual number of sensory fibers that is affected by the injury that is important, but rather the overall impact that TBI has had on the nerves that are responsible for processing sensations. The more significant the damage to the sensory fibers, the more likely it is that they will fail when it comes to transmitting the information that the brain needs to perform at an optimum level.