More reasons to get a goodnight's rest. Sleep-deprived brain can't form memories

February 13, 2017

Washington, Feb 13: If you don't get enough sleep, you might just start forgetting things. Sleep deprivation can interfere with the process that helps reinforce our memories, a new study has found.

sleepAfter studying mice, researchers at Johns Hopkins University in the US have fortified evidence that a key purpose of sleep is to recalibrate the brain cells responsible for learning and memory so the animals can ‘solidify' lessons learned and use them when they awaken.

The researchers also report they have discovered several important molecules that govern the recalibration process, as well as evidence that sleep deprivation, sleep disorders and sleeping pills can interfere with the process.

“Our findings solidly advance the idea that the mouse and presumably the human brain can only store so much information before it needs to recalibrate,” said Graham Diering from Johns Hopkins University.

“Without sleep and the recalibration that goes on during sleep, memories are in danger of being lost,” said Diering.

Diering said that current scientific understanding of learning suggests that information is “contained” in synapses, the connections among neurons through which they communicate.

On the “sending side” of a synapse, signalling molecules called neurotransmitters are released by a brain cell as it “fires”; on the “receiving side,” those molecules are captured by receptor proteins, which pass the “message” along.

If a cell receives enough input through its synapses, it fires off its own neurotransmitters.

More specifically, experiments in animals have shown that the synapses on the receiving neuron can be toggled by adding or removing receptor proteins, thereby strengthening or weakening them and allowing the receiving neuron to receive more or less input from nearby signalling neurons.

When neurons are “maxed out” and constantly firing, they lose their capacity to convey information, stymying learning and memory. One possible reason that neurons do not usually max out is a process that has been well-studied in lab-grown neurons but not in living animals, asleep or awake.

Known as homeostatic scaling down, it is a process that uniformly weakens synapses in a neural network by a small percentage, leaving their relative strengths intact and allowing learning and memory formation to continue.

To find out if the process does occur in sleeping mammals, Diering focused on the areas of the mouse brain responsible for learning and memory: the hippocampus and the cortex.

He purified proteins from receiving synapses in sleeping and awake mice, looking for the same changes seen in lab-grown cells during scaling down.

Results showed a 20% drop in receptor protein levels in sleeping mice, indicating an overall weakening of their synapses, compared to mice that were awake.

The study appears in the journal Science.

Comments

Add new comment

  • Coastaldigest.com reserves the right to delete or block any comments.
  • Coastaldigset.com is not responsible for its readers’ comments.
  • Comments that are abusive, incendiary or irrelevant are strictly prohibited.
  • Please use a genuine email ID and provide your name to avoid reject.
Agencies
February 26,2020

Tokyo, Feb 26: Two more Indians onboard quarantined cruise ship -- Diamond Princess -- were tested positive for novel coronavirus, the Indian embassy here said on Tuesday, adding that those Indians not infected by the virus will be repatriated to the homeland on February 26.

A total of 16 Indian nationals onboard the luxury ship -- quarantined off the coast of Japan since February 5 -- have been tested positive for coronavirus so far, the embassy informed.

"A chartered flight is being arranged to repatriate Indian nationals onboard #DiamondPrincess, provided they have (a) consented; (b) not tested positive for #COVID19; (c) cleared by the medical team. An email advisory to this effect, with details, has been sent to them," the embassy tweeted.

The repatriation of the Indian nationals will be facilitated by the Indian government.

"PCR test results for ALL Indian nationals declared-02 more Indians tested positive to #COVID19, taking the total to 16. Those fulfilling conditions and consenting to repatriation to India on 26 Feb being facilitated by the Indian Government. Details shared with them," the following tweet read.

A total of 138 Indians, including 132 crew and 6 passengers, were among the 3,711 people on board the luxury cruise ship which was quarantine off Japan on February 5 after it emerged that a former passenger had tested positive for the virus.

Comments

Add new comment

  • Coastaldigest.com reserves the right to delete or block any comments.
  • Coastaldigset.com is not responsible for its readers’ comments.
  • Comments that are abusive, incendiary or irrelevant are strictly prohibited.
  • Please use a genuine email ID and provide your name to avoid reject.
News Network
July 11,2020

Istanbul, Jul 11: Turkish President Recep Tayyip Erdogan announced Friday that the Hagia Sophia, one of the architectural wonders of the world, would be reopened for Muslim worship, sparking fury in the Christian community and neighbouring Greece.

His declaration came after a top Turkish court revoked the sixth-century Byzantine monument's status as a museum, clearing the way for it to be turned back into a mosque.

The UNESCO World Heritage site in historic Istanbul, a magnet for tourists worldwide, was first constructed as a cathedral in the Christian Byzantine Empire but was converted into a mosque after the Ottoman conquest of Constantinople in 1453.

The Council of State, Turkey's highest administrative court, unanimously cancelled a 1934 cabinet decision to turn it into a museum and said Hagia Sophia was registered as a mosque in its property deeds.

The landmark ruling could inflame tensions not just with the West and Turkey's historic foe Greece but also Russia, with which Erdogan has forged an increasingly close partnership in recent years.

'Millions of Christians not heard'

Greece swiftly branded the move by Muslim-majority Turkey an "open provocation to the civilised world".

"The nationalism displayed by Erdogan... takes his country back six centuries," Culture Minister Lina Mendoni said in a statement.

The Russian Orthodox Church was equally scathing.

"The concern of millions of Christians were not heard," Church spokesman Vladimir Legoida told Interfax news agency.

The decision "shows that all pleas regarding the need to handle the situation extremely delicately were ignored," he said.

UNESCO chief Audrey Azoulay said she "deeply regrets" the decision made without prior dialogue with the UN's cultural agency.

The move was also condemned by the US Commission on International Religious Freedom, which said it was an "unequivocal politicisation" of the monument.

Hagia Sophia, which stands opposite the impressive Sultanahmet Mosque -- often called the Blue Mosque, has been a museum since 1935 and open to believers of all faiths.

Transforming it from a mosque was a key reform under the new republic born out of the ashes of the Ottoman Empire.

Sharing a presidential decree which named Hagia Sophia as a "mosque", Erdogan announced its administration would be handed over to Turkey's religious affairs directorate known as Diyanet.

"May we be blessed," he commented. The decree was published on the official gazette.

Erdogan has in recent years placed great emphasis on the battles which resulted in the defeat of Byzantium by the Ottomans, with lavish celebrations held every year to mark the conquest.

Muslim clerics have occasionally recited prayers in the museum on key anniversaries or religious holidays.

"The decision is intended to score points with Erdogan's pious and nationalist constituents," said Anthony Skinner of the risk assessment firm Verisk Maplecroft.

"Hagia Sophia is arguably the most conspicuous symbol of Turkey's Ottoman past -- one which Erdogan is leveraging to strengthen his base while snubbing domestic and foreign rivals," he told AFP.

'Chains broken'

A few hundred Turks carrying Turkish flags gathered outside Hagia Sophia shouting "Chains broken, Hagia Sophia reopened".

Police heightened security measures around the building, according to AFP journalists.

"It's been a dream since we were kids," said Erdal Gencler, an Istanbul resident.

"(Hagia Sophia) finds its true purpose again. We are very excited, proud, and hopeful that there will be beautiful services here," he added.

Fatma, a woman with tearful eyes, said: "Of course I am crying. (Hagia Sophia) belongs to us."

Ahead of the court decision, Justice Minister Abdulhamit Gul shared a picture of Hagia Sophia on his official Twitter account, with a message: "Have a good Friday."

Finance Minister Berat Albayrak, Erdogan's son-in-law, tweeted that Hagia Sophia would be reopened to Muslim worship "sooner or later", referring to a quote from Turkish poet Necip Fazil Kisakurek.

The Council of State had on July 2 debated the case brought by a Turkish group -- the Association for the Protection of Historic Monuments and the Environment, which demanded Hagia Sophia be reopened for Muslim prayers.

Since 2005, there have been several attempts to change the building's status. In 2018, the Constitutional Court rejected one application.

Despite occasional protests outside the site by Islamic groups, Turkish authorities had until now kept the building as a museum.

Comments

Add new comment

  • Coastaldigest.com reserves the right to delete or block any comments.
  • Coastaldigset.com is not responsible for its readers’ comments.
  • Comments that are abusive, incendiary or irrelevant are strictly prohibited.
  • Please use a genuine email ID and provide your name to avoid reject.
Agencies
March 26,2020

Madrid, Mar 26: More than three billion people around the world were living under lockdown on Wednesday as governments stepped up their efforts against the coronavirus pandemic which has left more than 20,000 people dead.

As the number of confirmed cases worldwide soared past 450,000, UN Secretary General Antonio Guterres warned that only a concerted global effort could stop the spread of the virus.

In Spain, the number of fatalities surpassed those of China, where the novel coronavirus first emerged three months ago, making it the hardest-hit nation after Italy.

A total of more than 20,800 deaths have now been reported in 182 countries and territories, according to an AFP tally.

Stock markets rebounded after the US Congress moved closer to passing a $2.2 trillion relief package to prop up a teetering US economy.

In Washington, President Donald Trump said New York, the epicenter of the US outbreak with over 30,000 cases, likely has a few "tough weeks" ahead but he would decide soon whether unaffected parts of the country can get back to work.

"We want to get our country going again," Trump said. "I'm not going to do anything rash or hastily.

"By Easter we'll have a recommendation and maybe before Easter," said Trump, who had been touting a strong US economy as he faces an election in November.

UN chief Guterres said the world needs to ban together to stem the pandemic.

"COVID-19 is threatening the whole of humanity -- and the whole of humanity must fight back," Guterres said, launching an appeal for $2 billion to help the world's poor.

"Global action and solidarity are crucial," he said. "Individual country responses are not going to be enough."

India's stay-at-home order for its 1.3 billion people is now the biggest, taking the total number of individuals facing restrictions on their daily lives to more than three billion.

Anxious Indians raced for supplies after the world's second-biggest population was ordered not to leave their houses for three weeks.

Russia, which announced the death of two patients who tested positive for coronavirus on Wednesday, is expected to follow suit.

President Vladimir Putin declared next week a public holiday and postponed a public vote on controversial constitutional reforms, urging people to follow instructions given by authorities.

In Britain, heir to the throne Prince Charles became the latest high-profile figure to be infected, though he has suffered only mild symptoms.

The G20 major economies will hold an emergency videoconference on Thursday to discuss a global response to the crisis, as will the 27 leaders of the European Union, the outbreak's new epicenter.

China has begun to relax its own draconian restrictions on free movement in the province of Hubei -- where the outbreak began in December -- after the country reported no new cases.

Crowds jammed trains and buses in the province as people took their first opportunity to travel.

But Spain saw the number of deaths surge to more than 3,400 after 738 people died in the past 24 hours and the government announced a 432-million-euro ($467 million) deal to buy medical supplies from Beijing.

The death toll in Italy jumped in 24 hours by 683 to 7,503 -- by far the highest of any country.

The number of French deaths was up by 231 on Wednesday to more than 1,330, and metro and rail services in Paris were cut to a minimum.

Spain and Italy were joined by France and six more EU countries in urging Germany and the Netherlands to allow the issue of joint European bonds to cut borrowing costs and stabilise the eurozone economy.

The call is likely to fall on deaf ears when EU leaders talk on Thursday -- with northern members wary of pooling debt with big spenders -- but they will sign off on an "unprecedented" recovery plan.

At La Paz University Hospital in Madrid, nurse Guillen del Barrio sounded bereft as he related what happened overnight.

"It is really hard, we had feverish people for many hours in the waiting room," the 30-year-old told AFP.

"Many of my colleagues were crying because there were people who are dying alone, without seeing their family for the last time."

Coronavirus cases are also spreading in the Middle East, where Iran's death toll topped 2,000, and in Africa, where Mali declared its first case and several nations announced states of emergency.

In Japan, which has postponed this year's Olympic Games, Tokyo's governor urged residents to stay home this weekend, warning of a possible "explosion" of the coronavirus.

Jerusalem's Church of the Holy Sepulchre, believed by Christians to house Christ's tomb, was shut as Israel tightened movement restrictions.

The impact of the pandemic is also hitting European football, with leagues and tournaments cancelled, while the fate of the Wimbledon tennis tournament could be decided next week.

The economic damage of the virus -- and the lockdowns -- could also be devastating, with fears of a worldwide recession worse than the financial meltdown more than a decade ago.

But financial markets rose after US leaders reached agreement on a stimulus package worth roughly 10 percent of the US economy, an injection Senate Majority Leader Mitch McConnell said represented a "wartime level of investment."

Meanwhile, more than half of all Americans have been told to stay at home, including residents of the largest state, California.

The United States has at least 65,700 cases and 942 people have died.

Comments

Add new comment

  • Coastaldigest.com reserves the right to delete or block any comments.
  • Coastaldigset.com is not responsible for its readers’ comments.
  • Comments that are abusive, incendiary or irrelevant are strictly prohibited.
  • Please use a genuine email ID and provide your name to avoid reject.