Saturday, October 31, 2015

How memories form and how we lose them

Did you know that as we get older, the hippocampus loses 5% of its neurons every decade? That amounts to a total loss of 20% by the time we are 80 years old - which helps explain why our memories seem to fade.

One leading cause of chronic memory problems is stress. When we are constantly overloaded with work and personal responsibilities, our bodies are on hyperalert. This response has evolved from the physiological mechanism designed to make sure we can survive in a crisis. Stress chemicals help mobilize energy and increase alertness. However, with chronic stress our bodies become flooded with these chemicals, resulting in a loss of brain cells, and an inability to form new ones, which affects our ability to retain new information.

So take a break! And remember to thank yourself later.

Let’s look at how memories form in the first place. When you experience something – like dialing a phone number – the experience is converted into a pulse of electrical energy that zips along a network of neurons. Information first lands in short term memory where it’s available for anywhere from a few seconds to a couple of minutes. It’s then transferred to long-term memory through areas such as the hippocampus and finally to several storage regions across the brain. Neurons throughout the brain communicate at dedicated sites called synapses using specialized neurotransmitters. If two neurons communicate repeatedly a remarkable thing happens – the efficiency of communication between them increases. This process, called long-term potentiation, is considered to be a mechanism by which memories are stored long-term.

Watch TED lesson:

Animation by Patrick Smith
Educator: Catharine Young

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Friday, October 30, 2015

"Real People, Fake Arms" with Sandra Bullock

Fixing holes in the heart without invasive surgery

Repairing defects and ruptures deep inside the body may have just gotten a whole lot less invasive. Up until now, fixing damaged cardiac tissue, ulcers, hernias and holes in other places within patients has meant serious surgery and sutures to bring tissue together so it can repair itself.

A new much less invasive procedure that harnesses a catheter equipped with inflatable balloons and ultraviolet light-activated, biodegradable adhesive patches.

A team from Boston Children’s Hospital, Harvard and Brigham and Women’s Hospital catheter has successfully used the device in animals to repair holes in organs without needing to resort to risky major surgery and stitches that can erode tissue over time.

The device harnesses a newly developed light-activated glue that works in the wet, dynamic environment inside organs. This glue coats a patch, which can be delivered to the site where it’s needed and holds damaged tissue together. Over time the tissue heals and regrows over the patch as it slowly dissolves. The problem has been figuring out how to deliver the patch without still needing to resort to traditional surgery.

The team developed a delivery system that can travel through the body via blood vessels like current heart catheters. Once there, the catheter is pushed through the damaged tissue until its forward balloon is on one side and a rear balloon is on the other side.

The two balloons are inflated to hold the glue patch against the damaged tissue. A UV light within the catheter is turned on, activating the glue until it cures against the damaged tissue. Next, the two balloons are deflated and the catheter is retracted, leaving the patch in place. The whole operation can take minutes and without the need to do something major like stop a beating heart to make the repair.



Corina Marinescu

Jane Got A Gun avec Natalie Portman - Bande-Annonce VF

U.S. Request to Extradite Roman Polanski Denied by Polish Court

Ndreas Rentz/Getty Images

A Polish court rejected on Friday a U.S. request to extradite Roman Polanski for charges stemming from having sexual intercourse with a 13-year-old girl in the 1970s.
The Oscar-winning director did not appear in court for the ruling due to “emotional reasons,” his lawyer Jan Olszewski told the judge.
The filmmaker was convicted in 1977 of five charges after admitting to having sex with a minor. He served 42 days in prison after cutting a 90-day plea deal then fled the U.S. ahead of sentencing in 1978. He’s been considered a U.S. fugitive ever since.
Polanski has dual citizenship in Poland, where he grew up, and France. French law prohibits extradition of its citizens, but Polish law doesn’t.
Swiss authorities also turned down a U.S. extradition warrant and freed him in 2010, after placing Polanski under house arrest for nine months. He was detained there after traveling to the Zurich Film Festival to accept a lifetime achievement award.
The verdict is subject to appeal within seven days.
VARIETY Maane Khatchatourian News Editor, October 30, 2015 | 06:24AM PT

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