• Sweden edition

Swedish researchers reveal key to forming lasting memories

Published: 10 Nov 2009 08:30 GMT+01:00
Updated: 10 Nov 2009 08:30 GMT+01:00

Researchers at Sweden's Karolinska Institutet have uncovered the mechanism that controls how the brain creates long-term memories, marking a significant step forward for developing new treatments for Alzheimer's disease.

“We are constantly being swamped with sensory impression,” Professor Lars Olson, who led the study, said in a statement.

“After a while, the brain must decide what’s to be stored long term. It’s this mechanism for how the connections between nerve fibers are altered so as to store selected memories that we’ve been able to describe.”

Short-term memories occur as a result of chemical changes caused by altered signaling between different nerve cells in the brain, a process which is relatively well understood.

But scientists are less certain about how the brain converts sensory impressions into lasting memories, which are then stored in the cerebral cortex.

The researchers discovered that signaling via the nerve membrane’s nogo receptor 1 (NgR1) receptor molecule plays a key role in the formation of long-term memories.

When nerve cells are activated, the gene for NgR1 is switched off, leading the team to believe that this inactivation might be important in the creation of long-term memories.

Using genetically modified mice with an extra NgR1 gene that could remain active even when the normal NgR1 was switched off, Olson and his team were able to switch the animal’s ability to form lasting memories on and off by adding a substance to their drinking water.

“We found that the ability to retain something in the memory for the first 24 hours was normal in the genetically modified mice,” said Olson.

“However, two different memory tests showed that the mice had serious difficulties converting their normal short-term memories to long-term ones, the kind that last for months.”

The scientists hope that their findings will help in the development of new treatments for a variety of conditions which affect people’s memory, including those related to Alzheimer's and strokes.

Medicines which target the NgR1 receptor system, for example, could improve the brain’s ability to form long-term memories.

The research was conducted in collaboration with American researchers at the National Institute on Drug Abuse (NIDA) at the National Institutes of Health (NIH).

The findings are published in the Proceedings of the National Academy of Sciences (PNAS).

David Landes (david.landes@thelocal.se)

Don't miss...X
Left Right

Your comments about this article

18:47 November 10, 2009 by zircon
"Pickabar, pickabar, what was that again? I'm sure it means something, but I can't remember why... OH Yeah, now I remember... Pick up Bart from school..." The Simpsons, one episode. Good study!
21:44 November 10, 2009 by Nemesis
Another sucess for Swedish science. The Karolinska does it again.

The research in the Karolinska is world class and goes from strength to strength. I hope there sucess continues.
01:17 November 11, 2009 by code850
The journal PNAS who published these results has lost and still loosing its credibility. It is even the subject of jokes for serious scientist. It is difficult to say whether Karolinska 'has done it again', because the success of an institute should be estimated taking into account the amount of rubish research and misleading papers produced. Since there is no serious statistics on this issue we can not say well done karolinska institute.
13:25 November 12, 2009 by Nemesis
@ code850,

So I should judge american institutes by there publications in PNAS.

Thank you for informing me that all major US institutions are basically a joke.

The Karolinska researchers regularly publich in the journals Nature and Science. The Karolinska is one of the most respected insitutes on the entire planet, for very good reason. It is world class.

If you have an issue with Swedish researchers, why are you in Sweden?

@ zircon

The Simpsons are nothing to do with publishing research papers in scientific journals.
Today's headlines
Elections 2014
Most Swedes lack info ahead of EU vote
The Green Party is one of only two parties devoting their websites to the EU elections. Here campaign manager Emma Rung presents the party's posters. Photo: Leif R Jansson/TT

Most Swedes lack info ahead of EU vote

The majority of Swedes feel the country's political parties are not doing enough to inform them about the upcoming European Parliament elections. Only two of the eight parties have dedicated their homepages to the May 25th polls. READ () »

Fatal Norrköping Brawl
Local church tried to stop Norrköping murders
Swedish police on the scene following Monday's fatal brawl. File: TT

Local church tried to stop Norrköping murders

The Syrian-Orthodox Church in Ektorp had tried to quell tensions between two rival families just hours before bad blood spilled into a massive brawl and two brothers lost their lives. READ () »

JobTalk Sweden
'Foreigners don't need to show banks Swedish ID'
The bridge that connects Sweden to the European continent. File: L.E. Daniel Larsson/Flickr

'Foreigners don't need to show banks Swedish ID'

The Swedish agency that helps Europeans fight impediments to the EU principle of free movement has revealed an increase in complaints, including one from a foreign citizen unable to open a bank account in Sweden. READ () »

Eurovision 2014
Pig heart shatters in Sweden's Eurovision clip
Sanna Nielsen in the new clip. Photo: YouTube (screenshot)

Pig heart shatters in Sweden's Eurovision clip

Sweden's Eurovision hopeful Sanna Nielsen released the official video for the song Undo on Wednesday, a clip featuring leather, slow motion destruction, and a frozen pig's heart and some violence. READ () »

Software robot pinches Swedish flats in seconds
Swedish apartments. File: The Local

Software robot pinches Swedish flats in seconds

A Swedish landlord suspects that a property fixer has set up a software robot to sign up for new flats on the market within seconds, and is charging house hunters to use the service. READ () »

Swedish zoo fire 'kills only the spiders'
Photo: Johan Nilsson/TT

Swedish zoo fire 'kills only the spiders'

Twenty-five fire fighters were on hand on Wednesday night when a fire broke out in a southern Sweden animal park. The vast majority of the animals were unharmed, but the cluster of spiders wasn't so lucky. READ () »

Sweden Investor group posts sharp profit drop
File photo: Simon Cunningham/Flickr

Sweden Investor group posts sharp profit drop

Swedish investment giant Investor on Wednesday said its first-quarter profits slumped by a quarter, underlining Sweden's vulnerability to international instability. READ () »

Florida 'mystery knight' dies in Sweden
Michael Boatwright (R) and Medieval knight re-enactors.

Florida 'mystery knight' dies in Sweden

The "motel mystery" American who baffled US authorities by only speaking Swedish when he woke up from a coma last year has passed away, Swedish media reported on Wednesday. READ () »

Swedes open coffin of 850-year-old king
Photo: Bertil Ericson/TT

Swedes open coffin of 850-year-old king

UPDATED: Scientists pried open the 850-year-old casket of King Erik the Holy on Wednesday, hoping to find out more about the king, his crown, and his eating habits. READ () »

TeliaSonera announces first-quarter profit drop
TeliaSonera CEO Johan Dennelind. File photo: TT

TeliaSonera announces first-quarter profit drop

Stockholm-listed telecom operator TeliaSonera on Wednesday said profits had fallen in the first quarter, but hoped offering customers more data solutions in the future would turn things around. READ () »

People-watching April 23
Inside the 850-year-old king's coffin
Sponsored: South-eastern Sweden offers Öland beaches and more
Swedish underwear shop puts staff in front of the camera
IN PICTURES: The Local's Property of the Week - Täby
Sponsored: India+Sweden Week - India Unlimited
Sponsored: India+Sweden Week - A film, food, and finance feast
University applications rocket to record high
People-watching April 18-20
Kids in Victorian garb mark Swedish Easter
Swedish MP ordered chemtrail probe
Swedish supermarket Ica pulls contested Easter commercial off air
Swedish royals set baptism date for princess
People-watching April 16
Who's the prime minister's heir?
Alfie Atkins
Are children's books the key to families integrating in Sweden?
'Sweden Dem protests cater to party's martyr image'
'Swedish research grants were fantastic, but now it's like Australia'
Only in Sweden: The ten problems you'd never encounter elsewhere
Swedes stopped to take my picture, but didn't look me in the eyes
Business & Money
A swipe of the hand replaced cash and cards in Lund
Video: Oliver Gee finds out how to embrace The Swedish Hug
Abba duo hints at reunion
Flash mobs hug it out across Sweden
Stockholm School of Economics
Sponsored Article
Why a bachelor's degree is no longer enough
Latest news from The Local in Switzerland

More news from Switzerland at thelocal.ch

Latest news from The Local in Germany

More news from Germany at thelocal.de

Latest news from The Local in Spain

More news from Spain at thelocal.es

Latest news from The Local in France

More news from France at thelocal.fr

Latest news from The Local in Italy

More news from Italy at thelocal.it

Latest news from The Local in Norway

More news from Norway at thelocal.no

Blog Update: The Diplomatic Dispatch

28 October 15:16

The Green Growth Group Summit »

"Today on the 28 October in Brussels, a large group of key EU Ministers and business people, including UK Secretary of State for Energy and Climate Change Edward Davey, and Swedish Environment Minister Lena Ek, will meet to discuss green growth. They all have a stake in resolving a challenge which, although it is crucial..." READ »

jobs available
Swedish Down Town Consulting & Productions
Swedish Down Town Consulting & Productions is an innovative business company which provides valuable assistance with the Swedish Authorities, Swedish language practice and general communications. Call 073-100 47 81 or visit: