Navigation Links
How the gut feeling shapes fear
Date:5/22/2014

An unlit, deserted car park at night, footsteps in the gloom. The heart beats faster and the stomach ties itself in knots. We often feel threatening situations in our stomachs. While the brain has long been viewed as the centre of all emotions, researchers are increasingly trying to get to the bottom of this proverbial gut instinct.

It is not only the brain that controls processes in our abdominal cavity; our stomach also sends signals back to the brain. At the heart of this dialogue between the brain and abdomen is the vagus nerve, which transmits signals in both directions from the brain to our internal organs (via the so called efferent nerves) and from the stomach back to our brain (via the afferent nerves). By cutting the afferent nerve fibres in rats, a team of scientists led by Urs Meyer, a researcher in the Group of ETH Zurich professor Wolfgang Langhans, turned this two-way communication into a one-way street, enabling the researchers to get to the bottom of the role played by gut instinct. In the test animals, the brain was still able to control processes in the abdomen, but no longer received any signals from the other direction.

Less fear without gut instinct

In the behavioural studies, the researchers determined that the rats were less wary of open spaces and bright lights compared with controlled rats with an intact vagus nerve. "The innate response to fear appears to be influenced significantly by signals sent from the stomach to the brain," says Meyer.

Nevertheless, the loss of their gut instinct did not make the rats completely fearless: the situation for learned fear behaviour looked different. In a conditioning experiment, the rats learned to link a neutral acoustic stimulus a sound to an unpleasant experience. Here, the signal path between the stomach and brain appeared to play no role, with the test animals learning the association as well as the control animals. If, however, the researchers switched from a negative to a neutral stimulus, the rats without gut instinct required significantly longer to associate the sound with the new, neutral situation. This also fits with the results of a recently published study conducted by other researchers, which found that stimulation of the vagus nerve facilitates relearning, says Meyer.

These findings are also of interest to the field of psychiatry, as post-traumatic stress disorder (PTSD), for example, is linked to the association of neutral stimuli with fear triggered by extreme experiences. Stimulation of the vagus nerve could help people with PTSD to once more associate the triggering stimuli with neutral experiences. Vagus nerve stimulation is already used today to treat epilepsy and, in some cases, depression.

Stomach influences signalling in the brain

"A lower level of innate fear, but a longer retention of learned fear this may sound contradictory," says Meyer. However, innate and conditioned fear are two different behavioural domains in which different signalling systems in the brain are involved. On closer investigation of the rats' brains, the researchers found that the loss of signals from the abdomen changes the production of certain signalling substances, so called neurotransmitters, in the brain.

"We were able to show for the first time that the selective interruption of the signal path from the stomach to the brain changed complex behavioural patterns. This has traditionally been attributed to the brain alone," says Meyer. The study shows clearly that the stomach also has a say in how we respond to fear; however, what it says, i.e. precisely what it signals, is not yet clear. The researchers hope, however, that they will be able to further clarify the role of the vagus nerve and the dialogue between brain and body in future studies.


'/>"/>

Contact: Urs Meyer
urs-meyer@ethz.ch
41-788-981-790
ETH Zurich
Source:Eurekalert

Related medicine news :

1. Dampening of positive feelings found to predict postpartum depressive symptoms
2. New study finds feeling in control can help you live longer
3. Trivedi Master™ Dahryn Trivedi’s last Monthly Enhancement Program of the year touched the hearts of many, as people shared their feelings about Dahryn and her Energy Tran
4. Those Gut Feelings May be the Result of What You Eat
5. Food, Feelings, and Body Image Psycho-educational Group for Adolescent Girls Helps to Improve Self-Esteem, Avoid Eating Disorders
6. Feelings for fetus may vary smoking amount
7. Time to Rekindle the Honeymoon Feeling in Your Relationship? Dr. Bonnie Weil Launches Keys to a Successful Relationship
8. Canadians Feeling the Stress of Tax Season Should Remember to Take Their B Vitamins
9. Turning repulsive feelings into desires
10. Poor sleep can leave romantic partners feeling unappreciated
11. Words have feelings
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:1/19/2017)... ... January 19, 2017 , ... In 2009, Carol Bryan ... resulted in severe facial disfiguration. After four frightening years of isolation and emotional ... Medical Center, who removed the substances in a partial facial transplant through eight ...
(Date:1/19/2017)... ... January 19, 2017 , ... Workrite Ergonomics announced this ... The Tranquility privacy panel system was designed to deliver the ideal blend of ... noise and provide the visual privacy required to maintain concentration levels and increase ...
(Date:1/19/2017)... CA (PRWEB) , ... January 19, 2017 , ... Sam ... planning assistance to commercial and residential clients in the California Bay Area, is launching ... heart health in the region. , Heart disease is the primary killer of adult ...
(Date:1/19/2017)... ... January 19, 2017 , ... ... which serves Lawrenceville, New Jersey and the surrounding area, is inaugurating a ... sclerosis (ALS), more commonly known as Lou Gehrig's disease or motor neurone disease, ...
(Date:1/19/2017)... ... January 19, 2017 , ... ... Spring Create Real Impact contest from Impact Teen Drivers and California Casualty. Entries ... . , Educational grants totaling $15,000 will be awarded for the best ...
Breaking Medicine News(10 mins):
(Date:1/19/2017)... 19, 2017  Stealth BioTherapeutics Inc. ( Stealth ), ... dysfunction, today announced new additions to its senior leadership ... Medical Officer, and Daniel Geffken as interim ... Jim Carr , Pharm.D. has been promoted to Chief ... to welcome Doug and Daniel to our management team, ...
(Date:1/19/2017)... , January 19, 2017 According to a ... cryotherapy is set to witness a CAGR of 6.5% during the ... will continue to be the leading market for cryotherapy ... ... are emphasizing on ensuring affordable and adequate supply of gas in ...
(Date:1/19/2017)... , Jan. 19, 2017  Abaxis, Inc. (NasdaqGS: ... blood analysis instruments and consumables for the medical and ... discuss its financial results for the third quarter fiscal ... be at 4:15 p.m. ET on Thursday, January 26, ... third quarter fiscal year 2017 after the market closes ...
Breaking Medicine Technology: