Human Central Nervous System

Human Central Nervous System

The human nervous system may be conveniently subdivided into two divisions: the central nervous system (the brain and spinal cord) and the peripheral nervous system (the nerves extending to and from the central nervous system).

Spinal cord

The spinal cord of the central nervous system is a white cord of tissue passing through the bony tunnel made by the vertebrae. The spinal cord extends from the base of the brain to the bottom of the backbone. Three membranes called meninges surround the spinal cord and protect it. The outer tissue of the spinal cord is white (white matter), while the inner tissue is gray (gray matter).
Thirty-one pairs of projections called nerve roots extend out along each side of the spinal cord. The nerve roots are sites of axons belonging to sensory and motor neurons. A central canal in the spinal cord carries cerebrospinal fluid, which provides for the nutrition and gaseous needs of the cord tissue. The neurons of the spinal cord serve as a coordinating center for the reflex arc and a connecting system between the peripheral nervous system and the brain.

Brain

The brain of the central nervous system is the organizing and processing center. It is the site of consciousness, sensation, memory, and intelligence. The brain receives impulses from the spinal cord and from 12 pairs of cranial nerves coming from and extending to the senses and to other organs. In addition, the brain initiates activities without environmental stimuli.
Two major hemispheres, the left and the right hemispheres, make up the tissue of the brain. The outer portion of the brain consists of gray matter, while the inner portion is white matter. Three major portions of the brain are recognized: the hindbrain, the midbrain, and the forebrain.
The hindbrain consists of the medulla, cerebellum, and pons. The medulla is the swelling at the tip of the brain that serves as the passageway for nerves extending to and from the brain. The cerebellum lies adjacent to the medulla and serves as a coordinating center for motor activity; that is, it coordinates muscle contractions. The pons is the swelling between the medulla and midbrain. The pons acts as a bridge between various portions of the brain.
The midbrain lies between the hindbrain and forebrain. It consists of a collection of crossing nerve tracts and is the site of the reticular formation, a group of fibers that arouse the forebrain when something unusual happens.
The forebrain consists of the cerebrum, the thalamus, the hypothalamus, and the limbic system. The cerebrum contains creases and furrows called convolutions that permit the cerebral hemisphere to accommodate more than 10 billion cells. Each hemisphere of the cerebrum has four lobes, and activities such as speech, vision, movement, hearing, and smell occur in these lobes. Higher mental activities such as learning, memory, logic, creativity, and emotion also occur in the cerebrum.
The thalamus serves as an integration point for sensory impulses, while the hypothalamus synthesizes hormones for storage in the pituitary gland. The hypothalamus also appears to be a control center for such visceral functions as hunger, thirst, body temperature, and blood pressure. The limbic system is a collection of structures that ring the edge of the brain and apparently function as centers of emotion.
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How to Improve Your Brain Health

How to Improve Your Brain Health
10 Ways to Increase Memory, Concentration, and Cognitive Abilities

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A healthy brain not only improves your memory and concentration, it reduces the risk of Alzheimers and other diseases. Here are 10 ways to increase your cognitive skills.

Improving your brain health can protect you from dementias, increase your memory, and sharpen concentration. Everything you do affects your brain and intellectual skills.

“Whenever you read a book or have a conversation, the experience causes physical changes in your brain,” says science writer George Johnson, author of In the Palaces of Memory. “It's a little frightening to think that every time you walk away from an encounter, your brain has been altered, sometimes permanently.”

These expert-endorsed tips will improve the way your brain functions and increase your overall health.

10 Ways to Improve Your Brain Health

1. Do “neurobic” exercises to strengthen neural pathways. Certain cognitive exercises and brain games can create new associations between different brain parts, says neurobiologist Lawrence Katz of Duke University. Neurobics include getting dressed or showering in the dark, switching what you normally wear on one side to the other (e.g., put your watch or bracelet on your opposite wrist), using your opposite hand to brush your teeth, and cooking ethnic foods that you’ve never prepared before.

2. Limit your alcohol intake to keep your brain "big." The more alcohol you consume, the lower your brain volume becomes. Scientists at Wellesley College in Massachusetts found that low to moderate levels of alcohol helps protect your health from cardiovascular disease, but heavy drinking shrinks brains. These researchers define heavy drinking as more than 14 drinks per week, moderate drinking as 8 to 14 drinks per week, and low as less than 7 drinks per week. To improve your brain health, keep the alcohol consumption to a minimum.

3. Try something new to sharpen concentration. An active brain can slow the mental decline that comes with age. “A lifetime of good mental habits pays off,” says University of Alberta researcher Dr. Dennis Foth. “People who are curious at a young age are more likely to be mentally active and stay active as they age. And we found it's never too late to start. With a little effort, even people in their 70s and 80s can see dramatic improvements.” Memorizing poetry, learning a new musical instrument, or taking Spanish or French lessons are great ways to increase memory and sharpen concentration.
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4. Smell the sandalwood to increase your memory. “Natural scents have a direct pathway to the brain and research shows that some chemical constituents of aromatherapy oils, particularly…sesquiterpenes can cross the blood-brain barrier and increase oxygen flow to the brain,” says Michelle Schoffro Cook, doctor of natural medicine and author of The Brain Wash. Extra oxygen increases energy, immune function, positive moods, and learning. Frankincense and sandalwood are particularly effective at increasing oxygen levels in the brain. Aromatherapy also decreases stress (and stress decreases brain health).

5. Do the tango to strengthen cognitive abilities. Dance requires twists and turns that strengthens brain connections. Learning the cha-cha-cha can nourish brain cells, which translates to cognitive skills in the real world. “Exercise can protect the brain against environmental toxins by counteracting free radicals and reducing inflammation,” says Schoffro Cook, author of The Brain Wash. Physical activity is one of the best ways to promote the growth of new brain cells and reduce the risk of Alzheimer's.

6. Sleep to boost memory. Your brain requires huge amounts of energy to function properly; sleep boost memory and allows your brain to process information. “Though it's not sexy, the traditional sleep advice is still effective,” says Dr Rachel Morehouse of the Atlantic Sleep Centre. Sleep little – if at all – during the day because naps rob you of sleep at night. To improve your overall brain health, get up and go to bed at set times. Stay active but avoid exercising in the evening because it keeps you awake. Wind down before you go to bed with music or a book. To improve your memory, enjoy healthy food, eat light meals at night, and avoid caffeine.

7. Volunteer to lower your stress and increase mental functioning. “Good Samaritans have been found to have lower stress levels and a sense of well-being, factors that add up to better overall health, including brain health,” says Schoffro Cook, author of The Brain Wash. The brain benefits of volunteering include increased mental functioning and better communication skills. The key may be in the “helper’s high” – the sense of calmness and well-being that comes from helping others. Volunteering can also improve your brainy health by raising your self-esteem and feelings of self-efficacy.

8. Socialize with people to improve your memory. Talking can increase memory and cognitive skills, says Oscar Ybarra, a psychologist at the University of Michigan. Further, he believes that visiting with a friend or neighbor may be as helpful as doing a crossword puzzle. About his study, he said, “Short-term social interaction lasting for just 10 minutes boosted participants’ intellectual performance as much as engaging in so-called ‘intellectual’ activities for the same amount of time.”

9. Strive for variety. Don’t rely on a particular practice, supplement, or food to improve your brain health. Instead, incorporate different activities into your life. For instance, take a child hiking if you normally spend time with adults; go for a run instead of the usual yoga class. The more you challenge your brain and body, the healthier and stronger they become. Playing brain games can also improve your brain health.

10. Reduce your exposure to neurotoxins. Harmful chemicals, food additives, and chemically altered ingredients can harm your brain and body health. While it’s not possible to completely eliminate pollution from your environment, you can limit it. Pure products, organic produce, natural fragrances, whole foods, and fresh air will improve your brain health and sharpen concentration

Read more at Suite101: How to Improve Your Brain Health: 10 Ways to Increase Memory, Concentration, and Cognitive Abilities | Suite101.com http://l-pawlik-kienlen.suite101.com/how-to-improve-your-brain-health-a53255#ixzz1nSNfGgF9