Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Study charts origins of fear

16.09.2005


A team of researchers led by the University of Toronto has charted how and where a painful event becomes permanently etched in the brain – a discovery that has implications for pain-related emotional disorders such as anxiety and post-traumatic stress.



U of T physiology professor Min Zhuo and his colleagues Professor Bong-Kiun Kaang of Seoul National University in South Korea, and Professor Bao-Ming Li of Fudan University in China have identified where emotional fear memory and pain begin by studying the biochemical processes in a different part of the brain. In a paper published in the Sept.15 issue of Neuron the researchers use mice to show how receptors activated in the pre-frontal cortex, the portion of the brain believed to be involved with higher intellectual functions, play a critical role in the development of fear. Previous research had pointed to activation in the hippocampus, an area buried in the forebrain that regulates emotion and memory, as the origin of fear memory.

"This is critical as it changes how and where scientists thought fear was developed," says Zhuo, the EJLB-CIHR Michael Smith Chair in Neurosciences and Mental Health. "By understanding the biomolecular mechanisms behind fear, we could potentially create therapeutic ways to ease emotional pain in people. Imagine reducing the ability of distressing events, such as amputations, to be permanently imprinted in the brain."


Zhuo says that fear memory does not occur immediately after a painful event; rather, it takes time for the memory to become part of our consciousness. The initial event activates NMDA receptors – molecules on cells that receive messages and then produce specific physiological effect in the cell – which are normally quiet but triggered when the brain receives a shock. Over time, the receptors leave their imprint on brain cells.

By delivering shocks to mice, the researchers activated the NMDA receptors and traced a subunit of the molecule – a protein called NR2B – long believed to be associated with fear memory in the hippocampus and the amygdala, an almond-shaped structure in front of the hippocampus. To further test the protein’s influence, researchers reduced the amount in mice and found they were less hesitant to avoid shocks. "We tested the animals using both spatial and auditory cues," Zhuo says. "In one experiment, the mice received small shocks when entering a chamber and they developed fear memory. In another experiment, we used sound tones to be associated with shocks. When NR2B was blocked, they no longer avoided the chamber or reacted to the tone."

Zhuo and his team then studied the mice’s brain slices and discovered traces of NR2B in the pre-frontal cortex, supporting their theory that fear memory develops in that region. "By identifying NR2B in the pre-frontal cortex of the brain, we propose that fear memory originates from a network of receptors, rather than one simple area," Zhuo says. "It is more complex than previously thought."

The next step, according to Zhuo, is to determine how NR2B directly affects memory formation and storage in the brain. "While we know it exists in the hippocampus, amygdala and the pre-frontal cortex, we don’t know exactly how it alters them," Zhuo says. "Once we understand the implications for each part, we will be able to reduce levels of NR2B accordingly and effectively reduce fear memory. In the future, perhaps people can take therapeutic measures before experiencing a particularly discomforting situation." The University of Toronto Innovations Foundation is currently working with Zhuo to push for the translation of this finding into treatments.

Karen Kelly | EurekAlert!
Further information:
http://www.utoronto.ca

More articles from Studies and Analyses:

nachricht New study: How does Europe become a leading player for software and IT services?
03.04.2017 | Fraunhofer-Institut für System- und Innovationsforschung (ISI)

nachricht Reusable carbon nanotubes could be the water filter of the future, says RIT study
30.03.2017 | Rochester Institute of Technology

All articles from Studies and Analyses >>>

The most recent press releases about innovation >>>

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

Im Focus: Making lightweight construction suitable for series production

More and more automobile companies are focusing on body parts made of carbon fiber reinforced plastics (CFRP). However, manufacturing and repair costs must be further reduced in order to make CFRP more economical in use. Together with the Volkswagen AG and five other partners in the project HolQueSt 3D, the Laser Zentrum Hannover e.V. (LZH) has developed laser processes for the automatic trimming, drilling and repair of three-dimensional components.

Automated manufacturing processes are the basis for ultimately establishing the series production of CFRP components. In the project HolQueSt 3D, the LZH has...

Im Focus: Wonder material? Novel nanotube structure strengthens thin films for flexible electronics

Reflecting the structure of composites found in nature and the ancient world, researchers at the University of Illinois at Urbana-Champaign have synthesized thin carbon nanotube (CNT) textiles that exhibit both high electrical conductivity and a level of toughness that is about fifty times higher than copper films, currently used in electronics.

"The structural robustness of thin metal films has significant importance for the reliable operation of smart skin and flexible electronics including...

Im Focus: Deep inside Galaxy M87

The nearby, giant radio galaxy M87 hosts a supermassive black hole (BH) and is well-known for its bright jet dominating the spectrum over ten orders of magnitude in frequency. Due to its proximity, jet prominence, and the large black hole mass, M87 is the best laboratory for investigating the formation, acceleration, and collimation of relativistic jets. A research team led by Silke Britzen from the Max Planck Institute for Radio Astronomy in Bonn, Germany, has found strong indication for turbulent processes connecting the accretion disk and the jet of that galaxy providing insights into the longstanding problem of the origin of astrophysical jets.

Supermassive black holes form some of the most enigmatic phenomena in astrophysics. Their enormous energy output is supposed to be generated by the...

Im Focus: A Quantum Low Pass for Photons

Physicists in Garching observe novel quantum effect that limits the number of emitted photons.

The probability to find a certain number of photons inside a laser pulse usually corresponds to a classical distribution of independent events, the so-called...

Im Focus: Microprocessors based on a layer of just three atoms

Microprocessors based on atomically thin materials hold the promise of the evolution of traditional processors as well as new applications in the field of flexible electronics. Now, a TU Wien research team led by Thomas Müller has made a breakthrough in this field as part of an ongoing research project.

Two-dimensional materials, or 2D materials for short, are extremely versatile, although – or often more precisely because – they are made up of just one or a...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Fighting drug resistant tuberculosis – InfectoGnostics meets MYCO-NET² partners in Peru

28.04.2017 | Event News

Expert meeting “Health Business Connect” will connect international medical technology companies

20.04.2017 | Event News

Wenn der Computer das Gehirn austrickst

18.04.2017 | Event News

 
Latest News

Wireless power can drive tiny electronic devices in the GI tract

28.04.2017 | Medical Engineering

Ice cave in Transylvania yields window into region's past

28.04.2017 | Earth Sciences

Nose2Brain – Better Therapy for Multiple Sclerosis

28.04.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>