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The Central And Peripheral Nervous System

The central nervous system is comprised of the brain and spinal cord. The peripheral nervous system includes all peripheral nerves. The human brain is the center of the central nervous system in humans and the primary control center for the peripheral nervous system. The brain controls "lower", unconscious activities such as heartbeat, respiration, and digestion - these are known as autonomic functions. The brain also controls "higher" order, conscious activities, such as thought, reasoning, and abstraction. The human brain is more capable of these higher order activities than any other species' brain.

The human brain is the seat of the human mind - the set of cognitive processes related to perception, interpretation, imagination and memories, of which a person might or might not be aware. Beyond cognitive functions, the brain regulates autonomic processes related to essential body functions such as respiration and heartbeat.

Extended neocortical capacity allows humans some control over emotional behavior, but neural pathways between emotive centers of the brain stem and cerebral motor control areas are shorter than those connecting complex cognitive areas in the neocortex with incoming sensory information from the brain stem. Powerful emotional pathways can modulate spontaneous emotive expression regardless of attempts at cerebral self-control. Emotive stability in humans is associated with planning, experience and an environment that is both stable and stimulating, especially during early developmental years.

The 19th century discovery of a primary motor control area mapped to correspond with regions of the body led to popular belief that the brain was organized around a homunculus. A distorted figure drawn to represent the body's motor map in the pre-frontal cortex was popularly recognized as the brain's homunculus, but function of the human brain is far more complex.

The human brain appears to have no localized center of conscious control. Like the brains of other vertebrates, it derives consciousness from interaction among numerous systems within the brain. Executive decision-making functions rely on cerebral activities, especially those of the frontal lobes, but redundant and complementary processes within the brain result in a diffuse assignment of executive control that can be difficult to attribute to any single locale.

Test Your Brain Count every "F" in the following text: FINISHED FILES ARE THE RESULT OF YEARS OF SCIENTIFIC STUDY COMBINED WITH THE EXPERIENCE OF YEARS... The brain cannot process "OF". Incredible or what? Anyone who counts all 6 "F's" on the first go is a genius. Three is normal, four is quite rare. More Brain Stuff O lny srmat poelpe can raed tihs. cdnuolt blveiee taht I cluod aulaclty uesdnatnrd waht I was rdanieg. The phaonmneal pweor of the hmuan mnid, aoccdrnig to a rscheearch at Cmabrigde Uinervtisy, it deosn't mttaer in waht oredr the ltteers in a wrod a re, the olny iprmoatnt tihng is taht the frist and lsat ltteer be in the rghit pclae. The rset can be a taotl mses and you can sitll raed it wouthit a porbelm. Tihs is bcuseae the huamn mnid deos not raed ervey lteter by istlef, but the wrod as a wlohe. Amzanig huh? yaeh and I awlyas tghuhot slpeling was ipmorantt! According to the authors of Keep Your Brain Alive, brushing your teeth with your nondominant hand flushes your brain with neurotrophin, which causes your dendrites to grow. Juice your brain!

Mid-brain functions include routing, selecting, mapping and cataloguing information, including information perceived from the environment and information that is remembered and processed throughout the cerebral cortex. Endocrine functions housed in the mid-brain play a leading role in modulating arousal of the cortex and of autonomic systems.

Nerves from the brain stem complex where autonomic functions are modulated join nerves routing messages to and from the cerebrum in a bundle that passes through the spinal column to related parts of a body. Twelve pairs of cranial nerves, including some that innervate parts of the head, follow pathways from the medulla oblongata outside the spinal cord.

A definite description of the biological basis for consciousness so far eludes the best efforts of the current generation of researchers. But reasonable assumptions based on observable behaviors and on related internal responses have provided the basis for general classification of elements of consciousness and of likely neural regions associated with those elements. Researchers know people lose consciousness and regain it, they have identified partial losses of consciousness associated with particular neuropathologies and they know that certain conscious activities are impossible without particular neural structures.

A common myth is that human beings only use ten percent of our brains. This is false; we use our entire brains. The myth likely had its source in an advertisement or a misunderstanding of neurological research in the late 1800s or early 1900s. Some psychics help to prolong this myth by asserting that the "unused" ninety percent of the human brain is capable of exhibiting psychic powers, and can be trained to perform psychokinesis and extra-sensory perception. A less literal interpretation of the statement is, however, valid. It can be reasonably claimed that most people only use a very small fraction of the cognitive potential of their brain, even though all individual brain neurons are busily working. Various cultural inventions enable humans to better utilise their cognitive potential, such as reading, education, solving puzzles, critical thinking, etc.

A head injury is any trauma that leads to injury of the scalp, skull, or brain. The injuries can range from a minor bump on the skull to serious brain injury. Head injury is classified as either closed or open (penetrating). A closed head injury means you received a hard blow to the head from striking an object. An open, or penetrating, head injury means you were hit with an object that broke the skull and entered the brain. This usually happens when you move at high speed, such as going through the windshield during a car accident. It can also happen from a gunshot to the head.

There are several types of brain injuries. A concussion is a jarring injury to the brain. A person who has a concussion usually, but not always, passes out for a short while. The person may feel dazed and may lose vision or balance for a while after the injury. A brain contusion is a bruise of the brain. This means there is some bleeding in the brain, causing swelling. When the skull cracks it is called a skull fracture. Sometimes the edges of broken skull bones cut into the brain and cause bleeding or other injury. A hematoma is bleeding in the brain that collects and clots, forming a bump. A hematoma may not be apparent for a day or even as long as several weeks. So it's important to tell your doctor if someone with a head injury feels or acts oddly. Watch out for headaches, listlessness, balance problems or throwing up.

Brain Function The brain was one of the last parts of the human body to be explored scientifically. In the 19th century the Spanish neuroanatomist Santiago Ramón y Cajal used chemical dyes to define discrete areas of the brain, but the more sophisticated tools of the 20th century were required to assign functions to these areas. During the early part of the century the American neurosurgeon Wilder Graves Penfield (1891–1976) stimulated various parts of patients' brains during surgery and showed that various muscular and emotional functions resided in separate locations. Study of persons whose right and left hemispheres had been separated by injury showed that each half of the brain was primarily concerned with different activities. Development of sophisticated imaging devices at the U.S. National Institutes of Health in the 1970s allowed investigators to demonstrate the specific parts of the brain that control hearing, speech, and movement of the limbs. Equally important were discoveries of how nerves function. The chemical transmitter theory, which was developed in the 20th century, states that impulses pass from one nerve to another by a combination of electrical and chemical signals. Another important finding for physiology was the discovery during the 1970s that the brain regulates bodily functions by releasing hormones that are sent by the hypothalamus, an area of the brain, to influence the master gland, the pituitary gland. This work, by the American endocrinologists Roger Guillemin and Andrew Victor Schally, established a connection between emotions and biochemistry. In the medical area, treatments became available for the first time for the neurological diseases epilepsy and Parkinson's disease.

Every year, millions of people sustain a head injury. Most of these injuries are minor because the skull provides the brain with considerable protection. The symptoms of minor head injuries usually go away on their own. More than half a million head injuries a year, however, are severe enough to require hospitalization.

Learning to recognize a serious head injury, and implementing basic first aid, can make the difference in saving someone's life. In patients who have suffered a severe head injury, there is often one or more other organ systems injured. For example, a head injury is sometimes accompanied by a spinal injury.

Common causes of head injury include traffic accidents, falls, physical assault, and accidents at home, work, outdoors, or while playing sports. Some head injuries result in prolonged or non-reversible brain damage. This can occur as a result of bleeding inside the brain or forces that damage the brain directly.

The signs of a head injury can occur immediately or develop slowly over several hours. Even if the skull is not fractured, the brain can bang against the inside of the skull and be bruised. (This is called a concussion.) The head may look fine, but complications could result from bleeding inside the skull.

When encountering a person who just had a head injury, try to find out what happened. If he or she cannot tell you, look for clues and ask witnesses. In any serious head trauma, always assume the spinal cord is also injured. For a mild head injury, no specific treatment may be needed. However, closely watch the person for any concerning symptoms over the next 24 hours. The symptoms of a serious head injury can be delayed. While the person is sleeping, wake him or her every 2 to 3 hours and ask simple questions to check alertness, such as "What is your name?"

If a child begins to play or run immediately after getting a bump on the head, serious injury is unlikely. However, as with anyone with a head injury, closely watch the child for 24 hours after the incident. Over-the-counter pain medicine (like acetaminophen or ibuprofen) may be used for a mild headache. DO NOT take aspirin, because it can increase the risk of bleeding. Call immediately for emergency medical assistance if there is severe head or facial bleeding, the person is confused, drowsy, lethargic, or unconscious, the person stops breathing or you suspect a serious head or neck injury.

Head injuries can be serious. Bleeding, tearing of tissues and brain swelling can occur when the brain moves inside the skull at the time of an impact. But most people recover from head injuries and have no lasting effects. It's normal to have a headache and nausea, and feel dizzy right after a head injury. Other symptoms include ringing in the ears, neck pain, and feeling anxious, upset, irritable, depressed or tired.

Head Injury: Information and Answers to Commonly Asked Questions: A Family's Guide to Coping Saint Louis Univ. Provides general information and answers to commonly asked questions regarding the aspects of severe head injury. Topics include: the accident, types of head injury, symptoms and behavior, intensive care setting, prognosis and outcomes, emotional reactions, aspects of therapy, prevention, and glossary of terms. For the consumer.

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