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Herbs & Plants

Bloodroot (Sanguinaria canadensis)

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Botanical Name: Sanguinaria canadensis
Kingdom: Plantae
Order: Ranunculales
Family: Papaveraceae
Genus: Sanguinaria
Species: S. canadensis

Common Names: Bloodwort, Redroot, Red puccoon, Pauson Tetterwort, although that name is also used to refer to Chelidonium majus.

Parts Used: Root and rhizome
Habitat: Bloodroot is  native to eastern North America. It  grows in Rich woods. Across Canada to Nova Scotia; south from New England to Florida; west to Eastern Texas; north to Manitoba.

Description:
Bloodroot is a perennial, herbaceous flowering plant. It grows from 20 to 50 cm (7.9 to 19.7 in) tall. It has one large basal leaf, up to 12 cm (4.7 in) across, with five to nine lobes. The leaves and flowers sprout from a reddish rhizome with bright orange sap that grows at or slightly below the soil surface. The rhizomes grow longer each year, and branch to form colonies. Plants start to bloom before the foliage unfolds in early spring. After blooming the leaves expand to their full size and go summer dormant in mid to late summer.

The flowers bloom from March to May depending on the region and weather. They have 8-12 delicate white petals and yellow stamens, and two sepals below the petals, which fall off after the flowers open. The flower stems are clasped by the leaves. The flowers are pollinated by small bees and flies. Seeds develop in green pods 40 to 60 mm (1.6 to 2.4 in) long, and ripen before the foliage goes dormant. The seeds are round and black to orange-red when ripe, and have white elaiosomes, which are eaten by ants.

You may click to see the pictures.

Cultivation:
Bloodroot is cultivated as an ornamental plant. The double-flowered forms are prized by gardeners for their large showy white flowers, which are produced very early in the gardening season. Bloodroot flower petals are shed within a day or two of pollination so the flower display is short lived, but the double forms bloom much longer than the normal forms. The double flowers are made up of stamens that have been changed into petal looking like parts, making pollination more difficult.

History:
American Indians used root tea for rheumatism, asthma, bronchitis, lung ailments, laryngitis, fevers; also as an emetic. Root juice applied to warts; also used as a dye and a decorative skin stain.
A bachelor of the Ponca tribe would rub a piece of the root as a love charm on the palm of his hand, then scheme to shake hands with the woman he desired to marry. After shaking hands, the girl would be found willing to marry him in 5 to 6 days.
One of the earliest reported uses of bloodroot, or puccoon, as it was then commonly known, was a dye. John Smith reported in 1612 that “Pocones is a small roote that groweth in the mountaines, which being dryed and beate in powder turneth red; and this they use for swellings, aches, annointing their joints, painting their heads and garments . . . and at night where his lodging is appointed, they set a woman fresh painted red with Pocones and oile, to be his bedfellow.”

Constituents: Sanguinarine, Sanguidimerine, Cholerythrine, Protopine, Berberine, Copticine, Red resin.The root contains several alkaloids, most notably sanguinarine, which has shown antiseptic, anesthetic and anticancer activity. American Indians used the root for rhuematism, asthma, bronchitis, lung ailments, laryngyitis and fevers. The red-orange juice from the root was applied to warts, used as a dye and a decorative skin stain.

Medicinal Properties:    Antiseptic, antispasmodic, cathartic, diuretic, emetic, emmenagogue, expectorant, febrifuge, sedative, stimulant, and tonic.

Main Uses:

Bloodroot has been used as a diuretic, emetic, emmenagogue, expectorant, febrifuge, stimulant, and tonic. Bloodroot has been used historically in numerous topical preparations for the treatment of various skin cancers, and also for sores, warts, eczema, and other dermal & epidermal problems. It has also been used internally in herbal preparations for congestive lung conditions such as emphysema and chronic bronchitis. Studies find that sanguinarine, a compound found in bloodroot, kills bacteria, stops them from converting carbohydrates into gum tissue-eating acid, and blocks enzymes that destroy collagen in gum tissue. Some studies have shown small amounts to be even more effective in reducing dental plaque than chlorhexidine, the active ingredient in mouthwashes and the effects can last up to 4 hours. Some companies are now making toothpaste and mouthwash using it as an active ingredient. The root in a vinegar extract makes a very good antifungal wash for athlete’s foot. Prepared as a powder, bloodroot may be sniffed to treat nasal polyps.

The paste of the root has been recommended to remove warts and the powder is used in a number of cancer salves (a process too complicated for this monograph). Carcinomas of the human nose and ear have responded to topical treatment with a preparation containing bloodroot extract.
It is used when bronchitis, sub-acute or chronic asthma, croup, laryngitis, pharyngitis and deficient capillary (blood) circulation is indicated. It is used as a specific for asthma and bronchitis with feeble peripheral blood circulation.
Bloodroot has been used for many years by American Indians and herbal practitioners as a remedy for skin cancer. The fresh juice from the root, a concentrated tincture, or a salve containing capsicum and fresh juice concentrate has been used.

Contraindications:   In some cases, excessive doses of Bloodroot can cause low blood pressure, vertigo, tremors, vomiting, reduced pulse, shock, and coma. Large doses can be poisonous.

Some experts recommend the following doses:
Steep a level teaspoonful of the fresh root into a pint of boiling water for half an hour. Strain. When cold, take a teaspoonful 3 times a day.
As a tincture (1:5 in 60% alcohol), 2 drops three times a day.
As an extract (1:1 in 60% alcohol), 1 drop three times a day.

Other Uses:
Commercial uses of sanguinarine and bloodroot extract include dental hygiene products. The United States FDA has approved the inclusion of sanguinarine in toothpastes as an antibacterial or anti-plaque agent. However, the use of bloodroot in oral hygiene products is associated with the development of oral leukoplakia, a premalignant lesion which may develop into oral cancer. On 24 Nov 2003, the Colgate-Palmolive Company of Piscataway, New Jersey, United States commented by memorandum to the United States Food and Drug Administration that then-proposed rules for levels of sanguinarine in mouthwash and dental wash products were lower than necessary. However, this conclusion is controversial.

Some animal food additives sold and distributed in Europe such as Phytobiotics’ Sangrovit contain sanguinarine and chelerythrine. On 14 May 2003, Cat Holmes reported in Georgia Faces that Jim Affolter and Selima Campbell, horticulturists at the University of Georgia College of Agricultural and Environmental Sciences, were meeting with Phytobiotics to relate their research into commercial cultivation of bloodroot.

Plant dye:
Bloodroot is a popular red natural dye used by Native American artists, especially among southeastern rivercane basketmakers. The blood of the root (when cut open) was used as a dye. A break in the surface of the plant, especially the roots, reveals a reddish sap.

Warning!
Bloodroot is dangerous. It should only be used with
guidance of a trained herbalist or physician.

Disclaimer:
The information presented herein is intended for educational purposes only. Individual results may vary, and before using any supplements, it is always advisable to consult with your own health care provider.

Resources:
https://en.wikipedia.org/wiki/Sanguinaria
http://ncnatural.com/wildflwr/blodroot.html
http://www.ct-botanical-society.org/galleries/sanguinariacana.html

http://www.herbnet.com/Herb%20Uses_AB.htm

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Healthy Tips

Better Sleep From A to Zzzzz

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Stop counting sheep! Check out these tips for getting a good night’s sleep.

Adenosine
Cats nap soundly and often, possibly thanks to this natural substance. Harvard Medical School researchers found in 1997 that levels of adenosine rise before sleep and drop during it, indicating that adenosine may help us slip into slumber. Now the rush is on to determine whether a new sleeping pill could be made of synthetic adenosine. In the meantime we’re left with the current crop of prescription pills .

Babies
New moms often sleep poorly, regardless of whether their offspring sleep well. But even among nonparents, the mere threat of being awakened can disrupt sleep. It triggers what experts have dubbed on-call syndrome, named after the fitful sleep that afflicts emergency workers, medical students, and doctors. These people lose about 1½ hours of sleep when on call, even if their services are never needed, reports Thomas Roth, Ph.D., director of the sleep disorders and research center at Henry Ford Hospital, in Detroit. If you’re in an on-call situation, make up for a little lost sleep by napping for 30 minutes the next day.

Chronotherapy
Sleep problems often arise when the body’s internal clock gets out of kilter. As a result of travel across time zones or a series of late nights in their own hometown, people who once dozed off at 11 p.m. suddenly find that they can’t fall asleep until 3 a.m. and don’t want to awaken before noon. When this occurs, doctors recommend chronotherapy to gradually reset the body’s clock. In this process, sleep is delayed in three-hour increments. For example, someone who’s having trouble falling asleep at 11 p.m. might be told to stay up until 2 a.m. The next night, she stays up until 5 a.m., the next until 8 a.m. and so on, until she has circled the clock and readjusted her natural bedtime to 11 p.m.

Depression
Depression is just one of the health problems reported by people with chronic insomnia. The list also includes cardiovascular, gastrointestinal, and musculoskeletal ills. Insomniacs are four times as likely as the general population to be depressed, and daytime sleepiness can be a warning sign of a blue mood. Researchers aren’t sure which comes first — the depression or the sleep problem. Caution: The typical treatment for depression, antidepressant drugs, can often have a sedative effect as well.

Estrogen
Hormonal changes take a toll on sleep. “It’s not uncommon for women to feel fatigued and need more sleep than usual in the few days before menstruation,” says Margaret Moline, Ph.D., director of the sleep-wake disorders center at New York Hospital-Cornell Medical Center, in White Plains, N.Y.

Another hormone-linked sleep shortage begins just before menopause, at around age 49. “Women with hot flashes are aroused out of restful sleep every eight minutes, while those without hot flashes find their sleep disrupted an average of every 18 minutes,” says Suzanne Woodward, Ph.D., an assistant professor of psychiatry at Wayne State University, in Detroit.

Postmenopausal hormone replacement therapy can help relieve hot flashes, as can lowering the thermostat in your bedroom (for details, see “Temperature,” below).

Exxon Valdez
In perhaps the most famous of a long list of sleep-related disasters, this grounded oil tanker dumped 11 million gallons of crude oil into Alaska’s Prince William Sound. The third mate, who was at the helm, was sleep deprived. Need more incentive to get your nightly eight hours? Lack of sleep also contributed to the space shuttle Challenger explosion and the Chernobyl disaster, according to Stanley Coren, Ph.D., a professor of psychology at the University of British Columbia, in Vancouver, and the author of Sleep Thieves.

Falling Asleep
If you lie awake for an hour or more before dozing off, you have insomnia. About 20% of people have it occasionally; for 10% the condition is chronic. Most insomniacs turn to over-the-counter products such as sedating antihistamines for help. Only 4% take prescription sleeping pills, most often benzodiazepines, which should not be used for more than a month because they can cause dependence and rebound insomnia.

The latest research suggests that the best sleep inducer in people with chronic insomnia is behavioral therapy. A study done in 1998 at the Mayo Clinic, in Rochester, Minn., found that changes in habits can help eliminate persistent insomnia, and that the benefits last longer than those of sleeping pills. Techniques used included having patients attempt to deduce the causes of their insomnia and experiment with lifestyle changes, such as avoiding napping or evening exercise, to see what worked best for them.

Gallup Poll
One-third of American adults are hazardously sleepy, according to a 1997 Gallup Poll sponsored by the National Sleep Foundation (NSF) in Washington. Almost half of Americans — 41% — report getting less sleep than they need, while a third say daytime sleepiness has interfered with routine activities.

Hilton Hotels
Is there such a thing as a caffeine-free hotel room? Actually, there are 35 of them in Hilton hotels across the country. Though these “Sleep Tight” rooms have no coffeepot, they’re outfitted with everything you need for sound sleep, and at no extra charge. The rooms boast features that fitful sleepers might benefit from having in their own bedrooms: blackout drapes; double-paned windows; extra-insulated walls; and an alarm lamp that wakes sleepers with gradually increasing levels of light.

Insomniaphobia
People who miss a night or two of solid sleep often begin to lie awake fretting that they won’t be able to doze off. This fear is self-perpetuating. “We tell people with insomnia to take away their bedside clock,” says Dr. Moline. This tactic works particularly well with insomniaphobes, who tend to be clock watchers.

Jet Lag
It’s a bane of modern living that’s not confined to international travelers: Changing time zones, even within the U.S., can be enough to upset the sleep schedule. In fact, Harvard Medical School researchers reported in 1997 that even the end of daylight savings time in October may be enough to throw off the body’s internal clock and increase the risk of on-the-job accidents. Cautious use of melatonin can help reset the body clock, as can exposure to bright sunlight. Talk to your doctor or a sleep specialist about how to time the use of either therapy for maximum benefit.

Kids

As sleep-deprived as many adults are, kids often fare worse. Mary Carskadon, Ph.D., a professor of psychiatry and human behavior at Brown University, found more depressed moods, lower grades, and more severe behavioral problems among ninth and tenth graders who got fewer than seven hours of sleep a night than among teens who slept more.

Furthermore, as adolescents mature, their body clocks may shift so that their ideal wake-up time is about an hour later than it was in their early teens. The natural bedtime changes from 9:30 in young teens to 10:30 in those over age 14. This means that for a teenager, getting up at 6 a.m. is as difficult as awakening at 3 a.m. would be for an adult. As a result, schools in Minnesota, California, Florida, and Washington have already begun to delay school start times to synchronize them with teens’ ideal sleep schedule. Early reports are that grades and behavioral problems are improving.

Melatonin
Although nonprescription melatonin supplements have become popular as a sleep aid, the hormone isn’t a particularly powerful sleep inducer, according to Josephine Arendt, Ph.D., a professor of endocrinology at the University of Surrey, in England, who has studied melatonin since 1972. Indeed, its only known function in humans is as a “chronobiotic,” a regulator that helps the body adjust to seasonal time changes.

Many people have taken melatonin with no apparent harmful effects. Data showing that it may constrict the coronary arteries as well as create infertility, however, suggest that it is potent and should be used with caution, if at all.

According to the NSF, there are no valid scientific data to support the use of melatonin as a sleep promoter. If you take it as a remedy for jet lag, do so cautiously: At the very least, you could wind up on Japan time when you’re only going to London.

Narcolepsy

One in 1,000 people has this neurological disorder, with its hallmark symptoms: daytime sleepiness; sleep “attacks” in which a person is overwhelmed by the need to sleep; bad dreams; and cataplexy, a sudden loss of muscle control that might cause the knees to buckle.

Narcolepsy typically starts in one’s teens or early 20s, though it may go undiagnosed for years. Unfortunately, effective treatments are limited. Stimulants are prescribed for daytime sleepiness, and tricyclic antidepressants are often given for cataplexy. Two promising drugs, rohypnol and gamma hydroxy butyrate, or GHB, are available only to people in clinical trials and may remain largely inaccessible, because they can be fatal in high doses and have been used in date rapes. The good news is that another medication awaiting FDA approval, Provigil (modafinil), appears to keep patients awake without making them jittery, a side effect of other therapies.

Oversleeping
We all relish an extra hour of rest on an occasional Saturday morning, but researchers say oversleeping on weekends can be a clue to the extent of the sleep debt you’re building up during the workweek. If you sleep more than an hour late on weekends, try to increase the amount of sleep you get during the week.

Preparatory Napping
If you know you’re going to be shortchanging yourself on sleep, store up rest by napping ahead of time. William Anthony, Ph.D., a professor of psychiatric rehabilitation at Boston University and the author of The Art of Napping, coined the term “preparatory napping” and says good “naptitude” includes limiting naps to 15 minutes (a longer snooze may leave you groggy). Studies show napping improves skills and performance for hours afterward, and nappers report no greater sleep difficulties at night than non-nappers.

Restless Legs Syndrome
This annoying neurological condition triggers a pulling or crawling sensation in the legs that can be relieved only by movement. Because RLS disrupts sleep severely, it is often handled by sleep specialists. “It’s one of the toughest things we treat,” says Alex Clerk, M.D., director of the University of California at San Francisco/Stanford sleep disorders clinic.

According to the Restless Legs Syndrome Association in Rochester, Minn. (www.rls.org), the condition affects 3% to 8% of the population, though many people aren’t aware that the annoyance has a name, much less a treatment. Taking iron supplements, avoiding caffeine, and taking hot or cold baths helps many people, but dopaminergic or anticonvulsant drugs may eventually be needed.

Sleep Laboratories
Sleep science has surged in recent years, and there’s now a center specializing in treating sleep disorders within 150 miles of almost anyone in the U.S. Most sleep labs require an overnight stay while doctors, using wires and electrodes connected to a sleeping patient’s body, measure brain waves, eye and leg movement, and muscle tension. A microphone records snoring while airflow sensors track breathing. Technologists read each subject’s 1,000-page record to assess sleep quality and quantity.

If you decide to visit a sleep lab, check with your insurer to make sure you’ll be reimbursed for the test, which runs about $1,200. Because sleep science is a relatively new field, the treatment of sleep disorders is sometimes challenged by insurance companies. Avoid clinics that treat only sleep apnea, a breathing disorder; a good lab will diagnose and treat a variety of conditions.

Sleep Quotient
Generally speaking, adults require about eight hours of sleep a night; Americans average only six or seven hours. Sleep researchers agree, however, that it’s not how close we come to our sleep quotient that’s important, but how well we sleep. A common myth is that our need for sleep declines as we age. In fact, it’s sleep quality that may deteriorate. As both sexes age, says Dr. Moline, they find it harder to fall asleep; sleep may become more fragmented and nighttime awakenings occur more easily. If you’re awakening unrefreshed, talk to your doctor about screening for a possible sleep disorder.

Snoring
Not just a nighttime nuisance, snoring is also a symptom of sleep apnea, a condition in which the muscles in the nose and throat relax during sleep, causing breathing to stop for up to a minute at a time. The resulting strain can damage arteries, leading to high blood pressure.

Apnea’s most common symptoms are loud snoring and daytime sleepiness. The typical patient is an overweight, fortysomething man who snores, but women are at increased risk after menopause. It’s not yet clear whether this higher risk is hormone related or due to weight gain. “If a woman has very little space where the tongue and upper airway meet, is obese or has large tonsils,” she may be at greater risk, says Dr. Moline.

Premenopausal women with apnea may be particularly hard to diagnose, because their symptoms don’t show up on the standard sleep-lab workup. A special test that measures the pressure between lung surfaces inside the chest is often needed, according to Dr. Clerk.

Treatment for apnea has come a long way since the 1970s, when the only therapy was a tracheotomy. In 1981 researchers developed the continuous positive airway pressure (CPAP) device, a breathing apparatus worn during sleep to keep the airway from collapsing. Losing weight, avoiding alcohol and cigarettes, and not sleeping on one’s back can help minimize symptoms. When the CPAP isn’t effective, a procedure that uses radio-frequency waves can reshape tissues in the throat. For information about apnea, call the Sleep Apnea Association, in Washington, at 202-293-3650. To stop non-apnea snoring, try a flatter pillow. Puffy pillows keep the neck in a snore-promoting position.

Temperature
Lowering body temperature at bedtime may help insomniacs sleep better, says new research from New York Hospital-Cornell Medical Center. Taking a hot bath about 90 minutes before bedtime prompts a slight drop in body temperature, which may help you doze off. Your bedroom’s temperature is also a factor in how well you sleep: 60ºF to 65ºF is ideal.

Ultradian Rhythms
Adults sleep in these daily cycles, switching between REM (rapid eye movement) and non-REM sleep every 90 minutes in an astonishingly predictable pattern. The body produces much of its growth hormone during deep sleep, and an age-related drop in deep sleep may contribute to the bone density decline that leads to osteoporosis. So have that glass of warm milk before bed: You need the calcium.

Victims of Drowsy Drivers
Sleep-related crashes kill about 1,550 people each year and cause almost 40,000 nonfatal accidents, reports the National Highway Traffic Safety Administration, in Washington. These accidents are likeliest to occur after midnight and before 7 a.m., and are likelier than others to be fatal. Their sinister sign: no skid marks at the accident scene — a clue that the driver wasn’t awake to hit the brakes.

A 1999 NSF survey found that 17% of Americans had nodded off at the wheel. But even if a sleepy driver doesn’t doze, her reaction time can be delayed. Sleep deprivation also heightens the effects of alcohol. An adult who drinks the equivalent of two beers after four hours of rest averages 35 hazardous situations in a driving simulator, while someone who drinks the same amount after eight hours of sleep makes only five errors.

So how can you stay alert behind the wheel? The combination of a short nap and 200 milligrams of caffeine (the equivalent of roughly two cups of coffee) was the most effective emergency measure in a recent British study. Another strong deterrent: Check out the chilling memorial to victims of drowsy drivers at the Parents Against Tired Truckers Website, www.patt.org.

Websites
More information on sleep and sleep disorders can be found at the NSF Website, www.sleepfoundation.org, or by calling 888-41-AWAKE. For a list of sleep centers, check out the American Sleep Disorders Association site at www.asda.org.

Yawning
Despite the fact that we all do it, no one seems to know exactly why we yawn. Some experts hold that, like laughing or crying, yawning is a physical response to an emotional state — namely boredom — or fatigue. Frequent yawning may be a sign that you need to examine your sleep schedule.

Zinc
A deficiency of this mineral, or of iron, calcium or copper may be to blame for insomnia. If you’re losing sleep, try adding a multivitamin to your routine.

If you’re tired of feeling like you’re not at your best or like you’re not getting the sleep you need, then it’s time to take action! Sign-up for the National Sleep Foundation’s Sleep Challenge today!

Source:Reader’s Digest

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Sleep well to remember well

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Grey regions of the brain    talk to each other during deep sleep to produce great memory. T.V. Jayan on some recent findings:……....CLICK & SEE

Staying up all night studying does more harm than good  it leads to fuzzy memories the next day. In other words, our mental scrapbook’s ability to register fresh memories is seriously compromised if a good night’s sleep is denied, scientists say.

Neuroscientists have known for a while that sleep deprivation does hamper the consolidation of long-term memory    the exact mechanism of which  was unraveled recently by an India-born scientist and his colleagues in the US and Germany. But now a team of researchers from Harvard Medical School, Boston, has shown that lack of sleep not only fetters memory retention but also its very formation.

Matthew Walker and co-workers at the Harvard centre reported on February 11 in the online version of Nature Neuroscience that sleep before learning is crucial to preparing the brain for the next day’s memory formation. The findings, they say, are  worrying   considering society’s increasing erosion of sleep time.

The Harvard scientists scanned the brain’s hippocampus region   where everyday events are minted into fresh memories    using sophisticated functional Magnetic Resonance Imaging (fMRI)‘ technique. The study involved 28 volunteers in the age group of 18-30 years. The individuals were divided into two groups, with one made to stay awake for nearly 35 hours (two days and one night), and the other permitted to have a normal night’s sleep. The group that kept up was allowed to read books, take short walks, surf or chat on the Internet or play board games.

Towards the end of the second day, all participants were shown a slideshow of 150 pictures of landscapes, objects and non-celebrities. As they watched, their brains were mapped using fMRI. The scientists found that the mean recognition levels of the sleep-deprived group were about 20 per cent less than that of the other. The participants were then recalled after a full day’s break and asked to identify the slides they had earlier seen as a set of 75 fresh slides were added to the lot.  The volunteers who lacked sleep on the first day performed poorly, despite having had two nights to recover the lost sleep, the scientists said.

Your ability to learn is 20-40 per cent worse, that is, the difference between acing the exam and failing it miserably,  Walker told Know How.

While the work done by Walker and his associates conclusively proved that sleep before learning is vital, scientists had little clue about the brain mechanisms that help sleep to move and consolidate newly learnt things into long-term memory. All they knew was that for long-term storage, memories move from the hippocampus, one of the oldest regions of the brain, to the neocortex, the grey matter covering the hippocampus. This, they knew, occurred during deep, dreamless sleep.

All along, nearly for a generation, scientists thought that the hippocampus pushes the memory meant for long-term storage, or consolidation, to the neocortex. But Brown University scientist Mayank Mehta (who completed his doctoral studies from the Indian Institute of Science, Bangalore, and worked for a few years in quantum physics before moving to the US and neuroscience) and his colleagues recently proved this wrong. Their work, published in the November 2006 issue of Nature Neuroscience, showed that it is not the hippocampus that uploads information to the neocortex in a burst of brain cell communication but the neocortex that drives the dialogue.

To strike up a conversation between the hippocampus and the neocortex, the neurons from both the brain regions should be in sync. In other words, if the neocortical neurons display any activity, there should be corresponding firing among the hippocampal neurons. The previous studies failed to exhibit any such synchronous firing   which neuroscientists call phase locking  in the two regions. While neocortical neurons showed rhythmic activity during deep sleep, excitatory neurons in the hippocampus showed erratic activity.

What set Mehta thinking was that if these two parts of the brain talk during deep sleep, why didn’t they appear to be speaking the same language?

There were many reasons why scientists were unable to establish this link. One reason is that they were looking at the excitatory neurons in the hippocampus. Second, they were looking at the activity using extracellular electrodes where they can only measure the spiking activity (the rush of neurons),   Mehta told.

Mehta and his colleagues demonstrated that neurons from the neocortex work in tandem not with excitatory hippocampal neurons but what they call interneurons    inhibitory brain cells in the hippocampus. The study conducted in rats hence showed that the timing of activity or talk was the same in both the brain regions, with a small delay in the hippocampus    as if the inhibitory neurons in the hippocampus were echoing the speech in the neocortex.

What really helped Mehta to crack the mystery was his association with Nobel prize-winning German scientist Bert Sakmann. Mehta’s team used a ground breaking single-cell recording technique developed at Sakman’s laboratory at the Max Plank Institute for Medical Research in Heidelberg for recording electrical activity in rats   brains.   This technique has helped us in simultaneous measurement of electrical potential in single neurons from the hippocampus and the neocortex, Sakmann, who was in Delhi earlier this month for an Indo-EU science conference, told KnowHow.   This is by far the best technique available to accurately record electric activity of individual neurons,   Sakmann claims.

“The technique of looking inside a neuron and identifying the neural type was very important for the study. If you don’t differentiate which neuron you are recording from, it all seems like a mess,  says Mehta.

Sumantra Chattarji at the Bangalore-based National Centre for Biological Sciences admits that scientists knew the hippocampus records episodic memory whereas the neocortex plays a critical role in long-term memory storage. But they haven’t been able to get the correlation correct.   The new technique made all the difference,  says Chattarji.

This method of experimentally seeing how the two brain regions “talk” to each other may help them study other aspects of brain function such as perception and emotion, hopes Mehta.

Source:The Telegraph (Kolkata,India)