Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Different signal paths for spontaneous and deliberate activation of memories

11.03.2010
Entirely different signal paths and parts of the brain are involved when you try to remember something and when you just happen to remember something, prompted by a smell, a picture, or a word, for instance. This is shown by Kristiina Kompus in her dissertation at Umeå University in Sweden.

Imagine you are asked to remember what you were doing exactly one week ago. You would probably have to make quite a mental effort to sift through your memories. On another occasion, a smell, a picture, or a word might suddenly and unexpectedly trigger a vivid memory of something that happened to you.

Science still does not fully understand why our brain sometimes automatically supplies us with a memory that we have done nothing to deliberately call to mind, whereas why, on other occasions, we cannot remember things even though we make efforts to recall them.

The studies in Kristiina Kompus's dissertation show that these two different ways of remembering things are initiated by entirely different signal paths in the brain. Efforts to retrieve a specific memory are dealt with by the upper part of the frontal lobe. This area of the brain is activated not only in connection with memory-related efforts but also in all types of mental efforts and intentions, according to the dissertation. This part of the brain is not involved in the beginning of the process of unintentionally remembering something as a response to external stimuli. Instead, such memories are activated by specific signals from other parts of the brain, namely those that deal with perceived stimuli like smells, pictures, and words. Sometimes such memories are thought to be more vivid and emotional; otherwise they would not be activated in this way. But Kristiina Kompus's dissertation shows that this is not the case - memories do not need to be emotionally charged to be revived spontaneously, unintentionally. Nor do memories that are revived spontaneously activate the brain more than other ies.

The studies also reveal that our long-term memory is more flexible that was previously believed. There is not just one single neurological signaling path for reliving old memories but rather several paths that are anatomically separate. This discovery is important, since it helps us understand how we can help people who have a hard time remembering things, regardless of whether this is related to aging or to some disorder in the brain. It may also help people who are plagued by unpleasant memories that constantly haunt them. This can happen following traumatic experiences, but also in depression.

The dissertation uses a combination of two imaging methods for the brain: functional magnetic resonance imaging (fMRI) and electroencephalography (EEG). The methods yield different information about the function of the brain. By combining them, Kristiina Kompus has been able both to determine what part of the brain is activated and how the activation proceeds over extremely brief time intervals, on the order of milliseconds.

Kristiina Kompus is an English speaker. She can be reached at: Phone: +46 (0)90-786 51 86, ext. 12. Mobile: +46 (0)70-758 79 24 E-mail: kristiina.kompus@diagrad.umu.se

Pressofficer: Betil Born, +46-(0)703-88 60 58,bertil.born@adm.umu.se

Bertil Born | idw
Further information:
http://www.umu.se
http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-31873

More articles from Health and Medicine:

nachricht New study points the way to therapy for rare cancer that targets the young
22.11.2017 | Rockefeller University

nachricht Penn study identifies new malaria parasites in wild bonobos
21.11.2017 | University of Pennsylvania School of Medicine

All articles from Health and Medicine >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: New proton record: Researchers measure magnetic moment with greatest possible precision

High-precision measurement of the g-factor eleven times more precise than before / Results indicate a strong similarity between protons and antiprotons

The magnetic moment of an individual proton is inconceivably small, but can still be quantified. The basis for undertaking this measurement was laid over ten...

Im Focus: Frictional Heat Powers Hydrothermal Activity on Enceladus

Computer simulation shows how the icy moon heats water in a porous rock core

Heat from the friction of rocks caused by tidal forces could be the “engine” for the hydrothermal activity on Saturn's moon Enceladus. This presupposes that...

Im Focus: Nanoparticles help with malaria diagnosis – new rapid test in development

The WHO reports an estimated 429,000 malaria deaths each year. The disease mostly affects tropical and subtropical regions and in particular the African continent. The Fraunhofer Institute for Silicate Research ISC teamed up with the Fraunhofer Institute for Molecular Biology and Applied Ecology IME and the Institute of Tropical Medicine at the University of Tübingen for a new test method to detect malaria parasites in blood. The idea of the research project “NanoFRET” is to develop a highly sensitive and reliable rapid diagnostic test so that patient treatment can begin as early as possible.

Malaria is caused by parasites transmitted by mosquito bite. The most dangerous form of malaria is malaria tropica. Left untreated, it is fatal in most cases....

Im Focus: A “cosmic snake” reveals the structure of remote galaxies

The formation of stars in distant galaxies is still largely unexplored. For the first time, astron-omers at the University of Geneva have now been able to closely observe a star system six billion light-years away. In doing so, they are confirming earlier simulations made by the University of Zurich. One special effect is made possible by the multiple reflections of images that run through the cosmos like a snake.

Today, astronomers have a pretty accurate idea of how stars were formed in the recent cosmic past. But do these laws also apply to older galaxies? For around a...

Im Focus: Visual intelligence is not the same as IQ

Just because someone is smart and well-motivated doesn't mean he or she can learn the visual skills needed to excel at tasks like matching fingerprints, interpreting medical X-rays, keeping track of aircraft on radar displays or forensic face matching.

That is the implication of a new study which shows for the first time that there is a broad range of differences in people's visual ability and that these...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Ecology Across Borders: International conference brings together 1,500 ecologists

15.11.2017 | Event News

Road into laboratory: Users discuss biaxial fatigue-testing for car and truck wheel

15.11.2017 | Event News

#Berlin5GWeek: The right network for Industry 4.0

30.10.2017 | Event News

 
Latest News

Lightning, with a chance of antimatter

24.11.2017 | Earth Sciences

A huge hydrogen generator at the Earth's core-mantle boundary

24.11.2017 | Earth Sciences

Scientists find why CP El Niño is harder to predict than EP El Niño

24.11.2017 | Earth Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>