Until just a few years ago, doctors believed that the brain stopped making new neural connections - meaning that the memory began to get irreversibly worse - when the body stopped developing, usually in the early 20s. And doctors knew that, like any other part of the body, neurons weaken as people age. Loss of brain function due to neural breakdown was assumed to be a normal, unavoidable part of aging. It turns out they were wrong.

In the past few years, it has become clear that you can, in fact, make new neurons starting in your 20s and continuing well into old age. You can literally rewire the brain with new parts as the older parts wear out. How?

There are lots of things you can do right now to preserve, protect and enhance your gray matter.

1Physical exercise

A healthy body really does mean a healthy mind. In the last decade it became clear that regular exercise beneficially affects brain function. Exercise boosts brain power by stimulating formation of new brain cells (neurons), the process known as neurogenesis2. Also, exercise strengthens connections between those cells. Researchers have found the areas of the brain that are stimulated through exercise are associated with memory and learning1.

Physical exercise may even help prevent Alzheimer's disease. Several studies7-9 have confirmed that regular physical activity reduces the risk of cognitive decline and dementia in old age.

2Lifelong learning - your brain is a learning machine

For most of us, after we graduate from high school or college, our pursuit of new knowledge bottoms out over time. We may be masters at what we do, but we aren't learning new things. There is clear evidence10- 11 that education and learning produce favourable changes in the brain. Researchers believe that intellectual activity play a neuroprotective role against dementia. Some studies suggest that having a low level of formal education and poor linguistic skills is a risk factor for cognitive decline in later life.

But if you continue to learn and challenge yourself, your brain continues to grow, literally. Recent research12 have demonstrated that learning over time enhances memory and the survival of new brain cells. An active brain produces new connections between nerve cells that allow cells to communicate with one another. This helps your brain store and retrieve information more easily, no matter what your age.

How can you challenge yourself? Scientists agree that anything that is new and expands your knowledge will be effective:

• Learning to play a musical instrument
• Switching careers or starting a new one
• Starting a new hobby, such as crafts, painting, biking or bird-watching
• Learning a foreign language. According to the latest study speaking more than one language may slow the aging process in the mind.
• Staying informed about what's going on in the world
• Learning to cook new dish

If you let your brain be idle, it's not going to be in the best health.

3Mental stimulation

Stimulate your brain. Make sure you're actively problem-solving and having to use your memory. Just as physical activity keeps your body strong, mental activity keeps your mind sharp and agile. The more we think, the better our brains function - regardless of age. Without something to keep us mentally charged, our brains, like unused muscles, can atrophy, leading to a decline in cognitive abilities.

The study6, conducted by researchers at the Albert Einstein College of Medicine in New York, found that mentally active seniors reduced their risk of dementia by as much as 75 percent, compared to those who do not stimulate their minds. Researchers from the Princeton University13 found that simple cognitive stimulation such as Bingo can be of great value to the daily management of Alzheimer's patients.

Some good ways to stimulate your mind:

• Travel
• Going to museums
• Reading books, newspapers, or magazines
• Play 'thinking' games like cards, checkers, chess, crosswords, sudoku puzzles
• Scrabble or doing crossword puzzles
• Playing musical instruments
• Dancing
• Crafts such as drawing, painting, and ceramics
• Ditch the calculator once in while and forcing yourself to do the calculation
• Volunteering

4Social interaction - People are good medicine

"Social interaction" can be measured by how often people talk on the phone with friends, neighbors and relatives, how often they get together with them, how many people they can share their most private feelings and concerns with.

Socializing may have a protective effect on the brain because it's a form of mental exercise. Not only does interacting with people stimulate the brain, but it can also keep you sharp, because dealing with people can be pretty challenging. Strong social ties have been associated with lower blood pressure and longer life expectancies.

And having no social ties is believed to be an independent risk factor for cognitive decline in older persons.

A U.S. team found14 that talking to another person for 10 minutes a day improves memory and test scores. They found that socializing was just as effective as more traditional kinds of mental exercise in boosting memory and intellectual performance. They also found that the higher the level of social interaction, the better the cognitive functioning. Social interaction included getting together or having phone chats with relatives, friends and neighbors.

In a study of more than 2,800 people ages 65 or older, Harvard researchers15 found that those with at least five social ties - church groups, social groups, regular visits, or phone calls with family and friends - were less likely to suffer cognitive decline than those with no social ties.

5Sleep & Nap

Sleep plays a crucial role in brain development and growth.

One of the explanations the science has come up with for the healing power of sleep is that sleep may contribute to neurogenesis, the formation of new nerve cells in the brain16. New research in animals17 provides a clue about how the sleep deprivation harm the brains - reduces the number of new brain cells. Without sufficient sleep, neurons may not have time to repair all the damage, and so could malfunction during the day.

Sleep is necessary for the brain to process and consolidate knowledge and for memories to form. Neuroscientists say that during sleep the hippocampus (where memory is stored) becomes highly active and moves knowledge from short-term memory to long-term memory18- 19.

The memories laid down by the sleeping brain are of two kinds. Declarative memory is memory for information - facts, dates, and names. Procedural memory is what allows us to do things like play a musical instrument, ride a bicycle, or add up a bill. Scientists think these two types of memory are influenced by different parts of the sleep cycle. Slow wave sleep benefit mainly the consolidation of declarative memories. In contrast, rapid eye movement (REM) sleep seems to benefit procedural memory20.

According to animal studies, when you perform a task, the brain cells fire in a certain sequence. If you then fall asleep, the same cells automatically fire in an identical sequence without being distracted or disrupted by incoming visual stimuli.

There is a consistent pattern: Learn something new during the day, consolidate what you have learned during a good night's sleep, then remember or perform the task better in the morning. However, sleep before learning is also critical in preparing the brain for next-day memory formation21.

Even a nap in the middle of the day may benefit some learning, according to a recent study5. Sleep appears to help "set" the declarative memories and make them easier to recall.

6Stress management

Scientists believe people exposed to chronic stress tend to have elevated levels of cortisol - a hormone produced by the adrenal glands in response to acute and chronic stress. High cortisol levels are dangerous to the brain.

Some of the most impressive effects of the stress on brain are hippocampus atrophy, shrinkage of the hippocampus or prefrontal cortex (the area of the brain unique to humans), and even neural death in some brain regions24, 28. The hippocampus, a vital brain region for episodic, spatial, and contextual memory, has many cortisol receptors, which makes it especially susceptible to stress.

Severe stress lasting weeks or months can impair cell communication in the brain's learning and memory region27. Increased stress hormones lead to memory impairment in the elderly and learning difficulties in young adults26.

Latest study provides the evidence that short-term stress has the same effect. Researcher from the University of California25 have found short-term stress lasting as little as a few hours can impair brain-cell communication in areas associated with learning and memory. They found that rather than involving the widely known stress hormone cortisol, which circulates throughout the body, acute stress activated selective molecules called corticotropin releasing hormones, which disrupted the process by which the brain collects and stores memories.

Stress is a constant in our lives and cannot be avoided. So, stress management is the key, not stress elimination. Several ways to help you manage stress in your daily life:

• See problems as opportunities
• Get away from the noise
• Exercise
• Learn relaxation techniques such as yoga and meditation
• Cut down on unnecessary responsibilities and avoid over-scheduling
• Make time for leisure activities
• Get a massage

7Laugh & Humor

Laughter is the best medicine! We've heard the expression time and again. Medical world has begun to take more serious notice of the healing power of humor and the positive emotions associated with it. By having fun and laughing, your stress levels decrease significantly. Humor stimulates the parts of our brain that use the "feel good" chemical messenger dopamine41. Also, researchers found that humor improves memory39- 40.

8Healthy breakfast

It might be the last thing on your morning to-do list, or it might not be on your list at all. However, many studies have shown that having breakfast improves the ability of concentration, reaction time, learning ability, mood and memory, whereas skipping breakfast reduces people's performance at school and at work42, 43.

A recent study done at Cardiff University in Wales found that subjects who ate a high-fiber cereal in the morning showed a 10 percent reduction in fatigue, lower incidence of depression, and better cognitive skills. Fiber helps slow down the absorption of food in the stomach, so you have more energy for a longer period of time.

9Omega-3 fatty acids

Omega-3 fatty acids are essential for brain health - they provide the physical building blocks necessary for the development and maintenance of the structural and functional integrity of the brain. In fact, one of the omega-3 fatty acids, commonly known as DHA (docosahexaenoic acid), makes up a large portion of the gray matter in the brain and is vital for brain cells function. Adding more DHA to your brain directly influences cell-to-cell communication, affects nerve conduction and neurotransmitter release, and other things that allow brain cells to send messages to each other29. One 1999 review of studies on DHA, published in the journal Pharmacological Research32, found that the nutrient is essential to normal brain function, and that a diet rich in DHA improves learning, while a lack of DHA causes learning ability to suffer.

French researchers4 looked at the diets of 8,085 people older than 65 who did not have dementia at the start of the study. Over the following four years, 183 of the participants developed Alzheimer's disease, and 98 developed another form of dementia. People who regularly consumed omega-3 rich oils, such as canola, flaxseed, and walnut oil, were 60 percent less likely to develop dementia than those who did not regularly consume such oils. The study also found that regular consumption of fruits and vegetables lowered dementia risk by 30 percent. People who ate fish at least once a week were 40 percent less likely to develop dementia.

Coldwater fish, such as salmon, tuna, mackerel, and herring are rich sources of omega-3 fatty acids (just be careful to eat this in moderation due to potential contamination with mercury). Dutch studies30- 31 revealed that high fish consumption may reduce the risk of dementia and cognitive decline.

10Blueberries

Would you believe that eating this tasty, low-glycemic superfood every day was found by the USDA at Tufts University33- 35 to slow and even reverse age-related brain decline, as well as improve short-term memory loss and help reverse age-related loss of balance?!

Blueberries are a major source of flavonoids, in particular anthocyanins and flavanols. Although the precise mechanisms by which these plant-derived molecules affect the brain are unknown, they have been shown to cross the blood brain barrier after dietary intake. It is believed that they exert their effects on learning and memory by enhancing existing neuronal connections, improving cellular communications and stimulating neuronal regeneration.

11Vegetables

Researchers found that eating vegetables appears to help keep the brain young and may slow the mental decline sometimes associated with growing old22. Cruciferous and green leafy vegetables including cauliflower, spinach, kale, broccoli, cabbage, brussels sprout and collards appear to be the most beneficial23. Researchers say that may be because they contain healthy amounts of vitamin E, an antioxidant that is believed to help fight chemicals produced by the body that can damage cells.

Three B vitamins, folic acid, B6, and B12, can help lower your homocysteine levels. Fortified cereal, other grains, and leafy green vegetables are good sources of B vitamins.

12Want to drink? Choose red wine!

While heavy drinking clearly causes serious problems for many people, drinking in moderation may be good for the brain.

Researchers found, intake of up to three daily servings of wine, unlike other alcohol beverages (liquor, beer), was associated with a lower risk of dementia37. This may be due to the ability of red wine polyphenols to protect brain cells against alcohol-induced damage38. There is well-documented evidence that resveratrol, a polyphenol found in red wine and red grape skin and seeds, has a significant antioxidant properties and produces neuroprotective effects36.

13Keep health problems under control

Many medical conditions, particularly those identified as risk factors for cardiovascular disease, are also risk factors for cognitive decline and dementia.

High blood pressure
High blood pressure in midlife increases the risk of cognitive decline in old age44. Use lifestyle modification to lower your blodd pressure.

Diabetes
Diabetes is an important risk factor for dementia45. You can improve blood glucose levels by eating healthy diet, exercising regularly, and staying lean. But if your blood sugar stays high, you'll need medication to achieve good control.

High cholesterol
High levels of LDL ("bad") cholesterol appear to significantly increase the risk of dementia46. Diet, exercise, weight control, and avoiding tobacco will go a long way toward improving your cholesterol levels.

High homocysteine
Research has shown that a higher than average blood level of homocysteine - a type of amino acid - is a strong risk factor for the development of Alzheimer disease and dementia47.

14Neurobics

Created by Lawrence C. Katz, Ph.D., a professor of neurobiology at Duke University Medical Center, neurobics is a unique system of brain exercises using your five physical senses and your emotional sense in unexpected ways that encourage you to shake up your everyday routines. Studies have shown that even small changes in daily patterns cause brain stimulation.

Neurobics can be done anywhere, anytime, in offbeat, fun and easy ways. These exercises can activate underused nerve pathways and connections, helping you achieve a fit and flexible mind:

• Drive to work a different route
• Get dressed with your eyes closed
• Brush your teeth with the other hand
• Unlock the door with your eyes closed
• Use your opposite hand to dial the phone or operate the TV remote
• Listen to music and smell flowers at the same time
• Shop at new grocery store

Research has suggested that using your left hand if you're left handed or your right if you're left handed more often, can help stimulate parts of the brain that you don't normally use.

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