Journal of Clinical and Diagnostic Research, ISSN - 0973 - 709X

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Dr Mohan Z Mani

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On Sep 2018




Prof. Somashekhar Nimbalkar

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Prof. Somashekhar Nimbalkar
Head, Department of Pediatrics, Pramukhswami Medical College, Karamsad
Chairman, Research Group, Charutar Arogya Mandal, Karamsad
National Joint Coordinator - Advanced IAP NNF NRP Program
Ex-Member, Governing Body, National Neonatology Forum, New Delhi
Ex-President - National Neonatology Forum Gujarat State Chapter
Department of Pediatrics, Pramukhswami Medical College, Karamsad, Anand, Gujarat.
On Sep 2018




Dr. Kalyani R

"Journal of Clinical and Diagnostic Research is at present a well-known Indian originated scientific journal which started with a humble beginning. I have been associated with this journal since many years. I appreciate the Editor, Dr. Hemant Jain, for his constant effort in bringing up this journal to the present status right from the scratch. The journal is multidisciplinary. It encourages in publishing the scientific articles from postgraduates and also the beginners who start their career. At the same time the journal also caters for the high quality articles from specialty and super-specialty researchers. Hence it provides a platform for the scientist and researchers to publish. The other aspect of it is, the readers get the information regarding the most recent developments in science which can be used for teaching, research, treating patients and to some extent take preventive measures against certain diseases. The journal is contributing immensely to the society at national and international level."



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Sri Devaraj Urs Medical College
Sri Devaraj Urs Academy of Higher Education and Research , Kolar, Karnataka
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Dr. Saumya Navit

"As a peer-reviewed journal, the Journal of Clinical and Diagnostic Research provides an opportunity to researchers, scientists and budding professionals to explore the developments in the field of medicine and dentistry and their varied specialities, thus extending our view on biological diversities of living species in relation to medicine.
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Dr Saumya Navit
Professor and Head
Department of Pediatric Dentistry
Saraswati Dental College
Lucknow
On Sep 2018




Dr. Arunava Biswas

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Dr. Arunava Biswas
MD, DM (Clinical Pharmacology)
Assistant Professor
Department of Pharmacology
Calcutta National Medical College & Hospital , Kolkata




Dr. C.S. Ramesh Babu
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Best regards,
C.S. Ramesh Babu,
Associate Professor of Anatomy,
Muzaffarnagar Medical College,
Muzaffarnagar.
On Aug 2018




Dr. Arundhathi. S
"Journal of Clinical and Diagnostic Research (JCDR) is a reputed peer reviewed journal and is constantly involved in publishing high quality research articles related to medicine. Its been a great pleasure to be associated with this esteemed journal as a reviewer and as an author for a couple of years. The editorial board consists of many dedicated and reputed experts as its members and they are doing an appreciable work in guiding budding researchers. JCDR is doing a commendable job in scientific research by promoting excellent quality research & review articles and case reports & series. The reviewers provide appropriate suggestions that improve the quality of articles. I strongly recommend my fraternity to encourage JCDR by contributing their valuable research work in this widely accepted, user friendly journal. I hope my collaboration with JCDR will continue for a long time".



Dr. Arundhathi. S
MBBS, MD (Pathology),
Sanjay Gandhi institute of trauma and orthopedics,
Bengaluru.
On Aug 2018




Dr. Mamta Gupta,
"It gives me great pleasure to be associated with JCDR, since last 2-3 years. Since then I have authored, co-authored and reviewed about 25 articles in JCDR. I thank JCDR for giving me an opportunity to improve my own skills as an author and a reviewer.
It 's a multispecialty journal, publishing high quality articles. It gives a platform to the authors to publish their research work which can be available for everyone across the globe to read. The best thing about JCDR is that the full articles of all medical specialties are available as pdf/html for reading free of cost or without institutional subscription, which is not there for other journals. For those who have problem in writing manuscript or do statistical work, JCDR comes for their rescue.
The journal has a monthly publication and the articles are published quite fast. In time compared to other journals. The on-line first publication is also a great advantage and facility to review one's own articles before going to print. The response to any query and permission if required, is quite fast; this is quite commendable. I have a very good experience about seeking quick permission for quoting a photograph (Fig.) from a JCDR article for my chapter authored in an E book. I never thought it would be so easy. No hassles.
Reviewing articles is no less a pain staking process and requires in depth perception, knowledge about the topic for review. It requires time and concentration, yet I enjoy doing it. The JCDR website especially for the reviewers is quite user friendly. My suggestions for improving the journal is, more strict review process, so that only high quality articles are published. I find a a good number of articles in Obst. Gynae, hence, a new journal for this specialty titled JCDR-OG can be started. May be a bimonthly or quarterly publication to begin with. Only selected articles should find a place in it.
An yearly reward for the best article authored can also incentivize the authors. Though the process of finding the best article will be not be very easy. I do not know how reviewing process can be improved. If an article is being reviewed by two reviewers, then opinion of one can be communicated to the other or the final opinion of the editor can be communicated to the reviewer if requested for. This will help one’s reviewing skills.
My best wishes to Dr. Hemant Jain and all the editorial staff of JCDR for their untiring efforts to bring out this journal. I strongly recommend medical fraternity to publish their valuable research work in this esteemed journal, JCDR".



Dr. Mamta Gupta
Consultant
(Ex HOD Obs &Gynae, Hindu Rao Hospital and associated NDMC Medical College, Delhi)
Aug 2018




Dr. Rajendra Kumar Ghritlaharey

"I wish to thank Dr. Hemant Jain, Editor-in-Chief Journal of Clinical and Diagnostic Research (JCDR), for asking me to write up few words.
Writing is the representation of language in a textual medium i e; into the words and sentences on paper. Quality medical manuscript writing in particular, demands not only a high-quality research, but also requires accurate and concise communication of findings and conclusions, with adherence to particular journal guidelines. In medical field whether working in teaching, private, or in corporate institution, everyone wants to excel in his / her own field and get recognised by making manuscripts publication.


Authors are the souls of any journal, and deserve much respect. To publish a journal manuscripts are needed from authors. Authors have a great responsibility for producing facts of their work in terms of number and results truthfully and an individual honesty is expected from authors in this regards. Both ways its true "No authors-No manuscripts-No journals" and "No journals–No manuscripts–No authors". Reviewing a manuscript is also a very responsible and important task of any peer-reviewed journal and to be taken seriously. It needs knowledge on the subject, sincerity, honesty and determination. Although the process of reviewing a manuscript is a time consuming task butit is expected to give one's best remarks within the time frame of the journal.
Salient features of the JCDR: It is a biomedical, multidisciplinary (including all medical and dental specialities), e-journal, with wide scope and extensive author support. At the same time, a free text of manuscript is available in HTML and PDF format. There is fast growing authorship and readership with JCDR as this can be judged by the number of articles published in it i e; in Feb 2007 of its first issue, it contained 5 articles only, and now in its recent volume published in April 2011, it contained 67 manuscripts. This e-journal is fulfilling the commitments and objectives sincerely, (as stated by Editor-in-chief in his preface to first edition) i e; to encourage physicians through the internet, especially from the developing countries who witness a spectrum of disease and acquire a wealth of knowledge to publish their experiences to benefit the medical community in patients care. I also feel that many of us have work of substance, newer ideas, adequate clinical materials but poor in medical writing and hesitation to submit the work and need help. JCDR provides authors help in this regards.
Timely publication of journal: Publication of manuscripts and bringing out the issue in time is one of the positive aspects of JCDR and is possible with strong support team in terms of peer reviewers, proof reading, language check, computer operators, etc. This is one of the great reasons for authors to submit their work with JCDR. Another best part of JCDR is "Online first Publications" facilities available for the authors. This facility not only provides the prompt publications of the manuscripts but at the same time also early availability of the manuscripts for the readers.
Indexation and online availability: Indexation transforms the journal in some sense from its local ownership to the worldwide professional community and to the public.JCDR is indexed with Embase & EMbiology, Google Scholar, Index Copernicus, Chemical Abstracts Service, Journal seek Database, Indian Science Abstracts, to name few of them. Manuscriptspublished in JCDR are available on major search engines ie; google, yahoo, msn.
In the era of fast growing newer technologies, and in computer and internet friendly environment the manuscripts preparation, submission, review, revision, etc and all can be done and checked with a click from all corer of the world, at any time. Of course there is always a scope for improvement in every field and none is perfect. To progress, one needs to identify the areas of one's weakness and to strengthen them.
It is well said that "happy beginning is half done" and it fits perfectly with JCDR. It has grown considerably and I feel it has already grown up from its infancy to adolescence, achieving the status of standard online e-journal form Indian continent since its inception in Feb 2007. This had been made possible due to the efforts and the hard work put in it. The way the JCDR is improving with every new volume, with good quality original manuscripts, makes it a quality journal for readers. I must thank and congratulate Dr Hemant Jain, Editor-in-Chief JCDR and his team for their sincere efforts, dedication, and determination for making JCDR a fast growing journal.
Every one of us: authors, reviewers, editors, and publisher are responsible for enhancing the stature of the journal. I wish for a great success for JCDR."



Thanking you
With sincere regards
Dr. Rajendra Kumar Ghritlaharey, M.S., M. Ch., FAIS
Associate Professor,
Department of Paediatric Surgery, Gandhi Medical College & Associated
Kamla Nehru & Hamidia Hospitals Bhopal, Madhya Pradesh 462 001 (India)
E-mail: drrajendrak1@rediffmail.com
On May 11,2011




Dr. Shankar P.R.

"On looking back through my Gmail archives after being requested by the journal to write a short editorial about my experiences of publishing with the Journal of Clinical and Diagnostic Research (JCDR), I came across an e-mail from Dr. Hemant Jain, Editor, in March 2007, which introduced the new electronic journal. The main features of the journal which were outlined in the e-mail were extensive author support, cash rewards, the peer review process, and other salient features of the journal.
Over a span of over four years, we (I and my colleagues) have published around 25 articles in the journal. In this editorial, I plan to briefly discuss my experiences of publishing with JCDR and the strengths of the journal and to finally address the areas for improvement.
My experiences of publishing with JCDR: Overall, my experiences of publishing withJCDR have been positive. The best point about the journal is that it responds to queries from the author. This may seem to be simple and not too much to ask for, but unfortunately, many journals in the subcontinent and from many developing countries do not respond or they respond with a long delay to the queries from the authors 1. The reasons could be many, including lack of optimal secretarial and other support. Another problem with many journals is the slowness of the review process. Editorial processing and peer review can take anywhere between a year to two years with some journals. Also, some journals do not keep the contributors informed about the progress of the review process. Due to the long review process, the articles can lose their relevance and topicality. A major benefit with JCDR is the timeliness and promptness of its response. In Dr Jain's e-mail which was sent to me in 2007, before the introduction of the Pre-publishing system, he had stated that he had received my submission and that he would get back to me within seven days and he did!
Most of the manuscripts are published within 3 to 4 months of their submission if they are found to be suitable after the review process. JCDR is published bimonthly and the accepted articles were usually published in the next issue. Recently, due to the increased volume of the submissions, the review process has become slower and it ?? Section can take from 4 to 6 months for the articles to be reviewed. The journal has an extensive author support system and it has recently introduced a paid expedited review process. The journal also mentions the average time for processing the manuscript under different submission systems - regular submission and expedited review.
Strengths of the journal: The journal has an online first facility in which the accepted manuscripts may be published on the website before being included in a regular issue of the journal. This cuts down the time between their acceptance and the publication. The journal is indexed in many databases, though not in PubMed. The editorial board should now take steps to index the journal in PubMed. The journal has a system of notifying readers through e-mail when a new issue is released. Also, the articles are available in both the HTML and the PDF formats. I especially like the new and colorful page format of the journal. Also, the access statistics of the articles are available. The prepublication and the manuscript tracking system are also helpful for the authors.
Areas for improvement: In certain cases, I felt that the peer review process of the manuscripts was not up to international standards and that it should be strengthened. Also, the number of manuscripts in an issue is high and it may be difficult for readers to go through all of them. The journal can consider tightening of the peer review process and increasing the quality standards for the acceptance of the manuscripts. I faced occasional problems with the online manuscript submission (Pre-publishing) system, which have to be addressed.
Overall, the publishing process with JCDR has been smooth, quick and relatively hassle free and I can recommend other authors to consider the journal as an outlet for their work."



Dr. P. Ravi Shankar
KIST Medical College, P.O. Box 14142, Kathmandu, Nepal.
E-mail: ravi.dr.shankar@gmail.com
On April 2011
Anuradha

Dear team JCDR, I would like to thank you for the very professional and polite service provided by everyone at JCDR. While i have been in the field of writing and editing for sometime, this has been my first attempt in publishing a scientific paper.Thank you for hand-holding me through the process.


Dr. Anuradha
E-mail: anuradha2nittur@gmail.com
On Jan 2020

Important Notice

Reviews
Year : 2010 | Month : February | Volume : 4 | Issue : 1 | Page : 2105 - 2110 Full Version

Sleep Strengthens Memories


Published: February 1, 2010 | DOI: https://doi.org/10.7860/JCDR/2010/.626
UMA DEVI P, MURUGAN S, SENAPATHY J G

School of Biotechnology, Karunya University, Coimbatore -641 114(India)

Correspondence Address :
Dr. Uma Devi Pongiya*,
Assistant Professor (SG),
School of Biotechnology and Health Sciences,
Karunya University, Coimbatore-114,
Mobile: +91 9994583372
E - mail: umadevipongiya@rediffmail.com

Abstract

Sleep has been identified as a state that optimizes the consolidation of newly acquired information in memory. Many evidences prove that both procedural and declarative memories are improved during sleep. Sleep does this through neurotransmitters and neurohormone secretion between its stages. While we sleep, our bodies secrete hormones that affect our mood, energy, memory and concentration. There occur two stages of sleep that include NREM (Non-Rapid Eye Movement) and REM (Rapid Eye Movement) sleep. Hippocampus-dependent memories benefit primarily from slow-wave sleep (SWS), whereas memories not depending on the hippocampus, show greater gains over periods containing high amounts of Rapid Eye Movement sleep. During sleep, the brain rewires its circuits to make sure that all newly gained knowledge is stored for future use. The parts of the brain that we use to learn a task become active again during sleep. This activity, scientists suggest, could be the brain transferring memory from short-term to long-term storage.

Keywords

Sleep, memory, neurotransmitters, hormone

Introduction

Sleep Isn't Just a Form of Rest
Sleep plays a critical physiological function and is indispensable for your intellectual development. Those who do not respect their sleep are not likely to live to their full mental potential. By cutting down on sleep, we learn less, we develop less, we are less bright, we make worse decisions, we accomplish less, we are less productive, we are more prone to errors and we undermine our true intellectual potential. Yet, some dramatic facts related to sleep deprivation slowly come into light (1). Many studies make it clear that sleep deprivation is dangerous. Sleep-deprived people who are tested by using a driving simulator or by performing a hand-eye coordination task perform as badly as, or worse than those who are intoxicated. Sleep deprivation also magnifies alcohol’s effects on the body and so a fatigued person who drinks, will become much more impaired than someone who is well-rested. Driver fatigue is responsible for an estimated 100,000 motor vehicle accidents and 1500 deaths each year, according to the National Highway Traffic Safety Administration (2). Since drowsiness is the brain’s last step before falling asleep, driving while drowsy can – and often does – lead to disaster. Caffeine and other stimulants cannot overcome the effects of severe sleep deprivation (3).

Sleep Enhances Memories
A good night's sleep triggers changes in the brain that help to improve memory. New memories are formed within the brain when a person engages with information to be learned (for example, memorizing a list of words or mastering a piano concerto). However, these memories are initially quite vulnerable; in order to "stick", they must be solidified and improved. This process of "memory consolidation" occurs when connections between the brain cells as well as between different brain regions are strengthened and for many years, it was believed to develop merely as a passage of time. More recently, however, it has been demonstrated that the time spent in sleep also plays a key role in preserving memory (4).

Procedural and Declarative Memory
Memory is possibly a person's most distinctive characteristic: it defines who we are and acts as a guide to our present and future. Psychologists have classified normal human memory into procedural and declarative memory. Procedural memory is used for skills such as riding a bike; while declarative memory is more concerned with knowing that a bicycle is called a bicycle (5).

By using functional magnetic resonance imaging (f-MRI), we can actually see which parts of the brain are active and which are inactive while subjects are being tested, thus enabling us to better understand the role of sleep in memory and learning. Fenn et al (6) of Harvard Medical School pointed out that the MRI results of the selected population have shown some areas of the brain were distinctly more active after a period of sleep and other areas were noticeably less active. But together, the changes brought about by sleep resulted in improvements in the subjects' motor skill performance.

"The cerebellum which functions as one of the brain's motor centers in controlling speed and accuracy, was clearly more active when the subjects had had a night of sleep," he explains. At the same time, the MRIs showed reduced activity in the brain's limbic system, the region that controls emotions such as stress and anxiety. "When you're asleep, it seems as though you are shifting memory to more efficient storage regions within the brain. Consequently, when you awaken, memory tasks can be performed more quickly and accurately and with less stress and anxiety"(4).

In the new work, researchers studied the influence of sleep on declarative memory in healthy, college-aged adults. The results demonstrated a robust effect: As compared to participants who did not sleep during the trials, those who slept between learning and testing were able to recall more of the original words that they had learned earlier. They demonstrated that sleep does not just passively and transiently protect memories; rather, sleep plays an active role in memory consolidation (7).

Physiology of Sleep
The human brain seems to be the highest achievement of biological evolution. It all started from a simple ability to conduct impulses. The hippocampus acts as the central switchboard that can easily store short-term memory patterns for the brain. During sleep, the brain works as hard as during SAT or GRE exams. It rewires its circuits to make sure that all newly gained knowledge is optimally stored for future use. Due to the physiological function of sleep, which is the rewiring of the neural network of the brain at the synapse level, we can naturally expect that the demand for sleep be associated with the amount of learning on the preceding days.

At the time when we usually go to sleep, there is a substantial circadian increase in melatonin released from the pineal gland. Melatonin is one of strong contributors to drowsiness. However, it is possible to sleep against the melatonin-serotonin cycle, which clearly indicates that it is not the only sleep regulator. At the same time, there is a significant drop in ACTH and cortisol, which are our alertness hormones. Similarly, the levels of serotonin drop and so does the body temperature. Once we rest in an undisturbed place, we drift into a dreamland. Actually, this is only the case in a well regulated sleeping cycle. People who cannot succumb to natural body rhythms will often be unable to follow the above scenario (1).
In the course of the night, we alternately enter two phases of sleep,
• NREM sleep (named for non-Rapid Eye Movement)
• REM sleep (named for Rapid Eye Movement)

Using EEG measurements, scientists were able to identify four phases of NREM sleep which correspond to progressively deeper sleep. As we close our eyes, it takes 3-15 minutes to enter Stage 1 NREM sleep (in a healthy and well-regulated individual). In this stage, we often experience little jerks associated with the impression of falling. Minor disturbances will wake us up and often we will even deny that we were asleep. Once State 1 NREM solidifies, we move towards Stage 2 NREM sleep which is still relatively light. After that, we move to Stage 3 and Stage 4 NREM (also called slow-wave sleep or deep sleep). One cannot learn effectively if your sleep gets cut short in the morning or if it gets interrupted during the night. Even if you try to sleep 15 hours per day in short pieces of interrupted sleep, your learning results will be dismal.

After 60-90 minutes of NREM sleep, there is a gradual increase in the activity of cells in the pontine tegmentum which is responsible for triggering REM sleep. During REM sleep, the cortex behaves as if you were awake. You experience dreams that seem to be generated by a random impulsation sent from the brainstem to the cortex. The cortex produces the best possible and most coherent imagery that it can. You experience connected events, real people, realistic scenery, all put together in the most improbable configurations. Yet, you cannot act upon your dreams (except for people with a disorder called violent sleeping). You often want to act in sleep (e.g. to escape a ferocious dog), yet you remain motionless. You feel as if mired in molasses. Only your eyes move rapidly and the muscles in your middle ear twitch. REM sleep is philogenetically younger than NREM sleep. Fish, amphibians or perhaps most reptiles do not show typical REM sleep. Yet, interestingly, REM sleep is present in both mammals and birds. This made some evolutionists hypothesize that REM sleep has been invented twice by evolution! The conclusion is that REM sleep plays a critical role for the survival of creatures with bird-mammal IQ levels. REM sleep is characterized by intense neural activity, increase in blood circulation and the use of oxygen, as well as an increase in the uptake of amino acids by the brain tissue. The brain in REM sleep is a hard-working brain that has little to do with the notion of energy-conservation and rest in sleep. A typical night will see you go five times through NREM-REM cycles, with each cycle lasting around 90 minutes and getting slightly shorter as the night progresses. Light impulses from the retina travel to the hypothalamus and SCN to produce a stop signal for the release of melatonin. Instead another neurohormone, serotonin were released,which in high level is responsible for what we feel as the morning sunshine happiness. It is also serotonin that is boosted by the popular antidepressant- Prozac. Unless you suffer from sleep phase advancement, always make sure the sunshine streams into your sleeping room in the morning to wake you up.

Role of Enzyme Mitogen-Activated Protein Kinase
Long-lasting memories are stored in the brain through strengthening of the connections or synapses between neurons. Researchers have known for many years that neurons must turn on the synthesis of new proteins for long-term memory storage and synaptic strengthening to occur, but the mechanisms by which neurons accomplish these tasks have remained elusive. The MIT (Massachusetts Institute of Technology) research team, led by Nobel laureate Susumu Tonegawa, director of the Picower Center for Learning and Memory, has now identified a crucial molecular pathway that allows neurons to boost their production of new proteins rapidly during long-term memory formation and synaptic strengthening. There is a direct activational signal from the synapse to the protein synthesis machinery, "The central component of this pathway, an enzyme called "mitogen-activated protein kinase" (MAPK), which effectively provides a molecular switch that triggers long-term memory storage by mobilizing the protein synthesis machinery. The synaptic stimulation normally activates MAPK and the activated form of MAPK in turn activates several key components of the protein synthesis machinery. This direct regulation of the protein synthesis machinery helps explain the observation that the activation of MAPK enhanced the production of a broad range of neuronal proteins (8).

Which Memories Are Restored In Sleep
Memories that are lost during the day may actually come back after a good night's sleep. But new research suggests that not all memories are equal and that some may be more likely to be forgotten than others. Researchers say that the task was like learning to understand someone speaking in a foreign language. The study showed that the performance declined over the span of a day, but completely recovered after a night's sleep and protects memories from decay; sleep also appears to restore memory.

In the second study, the short-term memory of the first exercise was lost in the process of immediately learning a second exercise. Sleep enhanced the memory of the exercise, but only of the second learned task and not the first. This is because the memory of the second learned exercise was not interfered with. But when the second exercise was learned six hours after the first, it did not interfere with the processing of the first and the performance and the memories of both were enhanced by sleep. Researcher Matthew P. Walker and colleagues of Harvard Medical School say that the findings showed that when memories are recalled, they shift back to an unstable state. Once reactivated, these memories may either be restored or lost if this process is interfered with (6).

Memory Consolidation during Rem and Nrem (Or Slow Wave Sleep) Sleep
Sleep causes memory consolidation by establishing a different pattern of neurotransmitters and neurohormone secretion between sleep stages. Another central role for consolidating memories is played by the slow oscillation, that is, the oscillating field potential change dominating SWS. The emergence of slow oscillations in neocortical networks depends on the prior use of these networks for encoding of information. Via efferent pathways, they synchronize the occurrence of sharp wave ripples accompanying memory reactivations in the hippocampus with thalamocortical spindle activity. Thus, hippocampal memories are fed back into neocortical networks at a time when these networks are depolarized and because of concurrent spindle activity, can most sensitively react to these inputs with plastic changes underlying the formation of long-term memory representations (9).

One of the functions of rapid eye movement (REM) sleep is to help memory processing. A research team headed by Pierre Maquet used positron emission tomography (PET) and brain blood flow measurements to assess brain function when people were learning a reaction time task and when they were sleeping. In the experiments, people were trained to press buttons when they saw certain symbols on a computer screen. The performance of these people on the reaction time task improved with practice and improved even more after they got a night's sleep. Dr. Maquet and his co-workers found that many of the brain areas that were activated when people performed the reaction time task were the same as those activated during REM sleep. During REM sleep, the visual cortex, premotor cortex, and some parts of the thalamus were more active in trained subjects than in untrained subjects. These were the same areas that showed significant activation during the reaction time task. These data suggest that areas of the brain which are important for learning the reaction time task are "reactivated" during REM sleep. The researchers believe that this reflects the importance of REM in memory processing, perhaps by strengthening memories (10).

Why Infants Need More Sleep
A good night's sleep may help your brain permanently file away lessons learned during the day. "Sleep appears to play a key role in human development," These findings may explain why children and teenagers need more sleep than adults and in particular, why infants sleep almost round the clock. They have an immense amount of new material to consolidate and consequently, this intensive period of learning may demand a great deal of sleep" (4).

Even More Reasons to Get Good Night's Sleep
As though improved memory isn’t enough incentive, there are many other reasons why getting plenty of shut-eye is a wise move. When we sleep:
• Muscle tissue is rebuilt and restored
• Growth hormone is secreted (this is important for kids but also for rebuilding tissue in adults)
• Mental energy is restored
And a good night's sleep is important for everything, from improving your mood and mental alertness to giving you energy and stamina to get through the day.
On the other hand, if you don't get the sleep you need:
• Your immune system may become impaired, leaving you less able to fight off disease
• You may feel irritable and have poor memory, poor concentration and mood swings
• You're more likely to feel angry, pessimistic and sad
• Your coordination, reaction time and judgment may all be negatively affected, which is particularly dangerous while driving

Conclusion

All of us need sleep to help reinforce memories and keep them from fading away. The researchers found that those who slept between learning and testing were able to recall what they have learned, more efficiently. The brain is more active during sleep to convert short-term to long-term memory storage. But some memories which are learned immediately and others are elapsed based on main concern. Sleep does not just passively and transiently protect memories; rather sleep plays an active role in memory consolidation. If you really want to remember something, study until bedtime. But don’t stay up all night. You may learn less, but you’ll remember a whole lot more. Some scientists say that sleep isn’t essential for storing memories. Until that is settled, it’s probably still better to be on the safe side, getting plenty of sleep.

References

1.
Piotr Wozniak, July 2000. Good sleep, Good learning, Good life, Available at: http://www.supermemo.com/articles/sleep.htm.
2.
Edel Jarboe, January 2004. Sleep Well, Be Well, Available at: http://www.pioneerthinking.com/ej_sleep.html
3.
Michael Bengston, March 2005. How much sleep do we need, Available at: http://www.patientlinx.com/sleepinsomnia/sleepamount.cfm
4.
Boston, June 2005. Study shows how sleep improves memory, Available at: http://www.hms.harward.edu/news/pressreleases/bid/0605sleep.htm
5.
Medical Research News, 10-july 2006. A good night’s sleep will help the memory, Available at: http://www.news-medical.net/?id=18792
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