Navigation Links
Neural Basis of Anxiety: Newer Insights

People suffering from anxiety tend to interpret confusing situations or those that may possibly be dangerous, as intimidating. Italian researchers from the Mouse Biology Unit of the European Molecular Biology Laboratory (EMBL), have now uncovered the neural basis for such anxiety behaviour in mice.

Their report, in the current issue of Nature Neuroscience, states that crucial roles played by a receptor for the messenger serotonin and a neural circuit involving a brain region called the hippocampus, is responsible for mediating fear responses in ambiguous situations.

A mouse that has learned that a certain cue, for example a tone, is always followed by an electrical shock comes to associate the two and freezes with fear whenever it hears the tone even if the shock is not delivered. But in real life the situation is not always so clear; a stimulus will only sometimes be followed by a threat while other times nothing might happen. Normal mice show less fear towards such ambiguous cues than to clearly threatening stimuli.

A team of researchers led by Cornelius Gross at the EMBL Mouse Biology Unit now discovered that this response to ambiguous stimuli requires a specific receptor molecule for serotonin, a signal many brain cells use to communicate. Mice that lack the serotonin receptor 1A have problems processing ambiguous stimuli and react to them with full-fledged fear responses. The cause is wrongly connected cells in their brains. Serotonin signalling is very important for brain development and if the receptor 1A is missing, defects arise in the wiring of the brain that affect the behaviour of mice later on in life.

"In humans serotonin signalling has been implicated in disorders including depression and anxiety and like our mice patients suffering from these conditions also overreact to ambiguous situations," Gross says. "The next step was to identify the brain regions that are responsible for such complex fea r behaviour and the processing of ambiguous cues."

Using a new technique to switch off neural activity in selective brain cells in living mice, Gross and his colleagues discovered that a specific part of the hippocampus is required for correct processing of ambiguous stimuli.

"Shutting down a specific circuit in the hippocampus abolished fear reactions only to ambiguous cues," says Theodoros Tsetsenis who carried out the research in Gross' lab. "The pathway must be involved in processing and assessing the value of stimuli. It seems to bias mice to interpret situations as threatening."

The hippocampus is mainly known as a region important for learning and memory, but the results reveal a more general role in evaluating information and assessing contingencies. Neural circuits that govern fundamental behaviours like fear are often often conserved between species and patient studies suggest a role for the hippocampus in anxiety also in humans.

The new insights gained into serotonin signalling via the receptor 1A and the role of the hippocampus in fear behaviour in mice promise to shed light on the neural basis of anxiety disorders and open up new avenues for therapies.


'"/>




Related medicine news :

1. Gamma Knife Offers New Hope For Trigeminal Neuralgia Patients
2. Botox Relieves Neuralgic Pain
3. Fetal Neural Grafts Improves Motor and Cognitive Function in Huntington Patients
4. A boon to the paralyzed -Brain Gate Neural Interface System
5. Research Reveal A New Angle On Neural Circuits.
6. Neural Stem Cells Reduce Parkinsons Symptoms in Monkeys
7. Genetics Might BE The Basis For Chronic Fatigue Syndrome
8. Molecular Basis Of ALS Found
9. Biological Basis for Homosexuality
10. Biological Basis Behind a Couch Potato
11. Basis for Nerve fiber Damage in Multiple Sclerosis Discovered
Post Your Comments:
*Name:
*Comment:
*Email:


(Date:2/13/2016)... ... ... With FCPX Overlay Embers from Pixel Film Studios users can now apply ... user can select from up to 40 effect overlays. With FCPX Overlay Embers users ... value, contrast, glow, and more all within a click of a mouse. , ...
(Date:2/13/2016)... , ... February 13, 2016 , ... ... of Nursing with an in-kind gift of a VeinViewer® Vision vein finder ... they learn how to start an IV and draw blood, combining technology with ...
(Date:2/13/2016)... (PRWEB) , ... February 13, 2016 , ... ... Tech Outlook’s top Clinical Data Management Solution Providers list for its expertise in ... functional and domain expertise to serve the technology needs of global clients. DDi ...
(Date:2/12/2016)... ... February 12, 2016 , ... The law firm of Morrow, Morrow, Ryan ... The purpose of these scholarships is to encourage applicants to pursue a degree in ... within these two parishes. , “We have available jobs in St. Landry and ...
(Date:2/12/2016)... Falls Church, VA (PRWEB) , ... February 12, 2016 , ... CDRH Enforcement Trends: , ... http://www.fdanews.com/cdrhenforcementtrends , As Winston Churchill said, “Those who don’t learn ... 2015 will show what to expect when they come knocking this year. But that takes ...
Breaking Medicine News(10 mins):
(Date:2/12/2016)... /PRNewswire/ - Demers Ambulances announces its first delivery in the state ... County Emergency Medical Services (EMS) consisting of four ... van. Quality Emergency Vehicles in Lecanto, FL ... This is the latest in Demers, ongoing expansion of sales.  ... Demers. --> Benoit LaFortune , Executive Vice President ...
(Date:2/12/2016)... Feb. 12, 2016   HeartWare International, Inc . ... and webcast to discuss its financial results for the ... Thursday, February 25, 2016 at 8:00 a.m. ET.  The ... the conference call and webcast.  On the conference call ... highlights from the fourth quarter and business outlook.   ...
(Date:2/12/2016)... Kalifornien, 12. Februar 2016  Sequent Medical, Inc. ... von Patienten für eine Studie zur Sicherheit und ... speziell für die Behandlung von rupturierten intrakraniellen Aneurysmen ... Leiter der Neuroradiologie an der Universitätsklinik Bicètre in ... der CLARYS-Studie hat den ersten Patienten aufgenommen. ...
Breaking Medicine Technology: