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Since 2008 – Progress Through Politics

Turning Anxiety Off?

We all experience anxiety from time to time. In “normal” amounts, it is a healthy feeling which warns us of potential dangers or motivates us to get things done. A moderate level of anxiety may in fact improve performance in many areas. In the average individual, occasional anxiety is simply part of the human condition. For many people around the world, however, anxiety is a plague. Excessive anxiety can be debilitating in the workplace, school environment, social network, and home. It can affect job and academic performance, and negatively impact our interpersonal relationships. In extreme cases, it can even make leaving the home a terrifying experience. We probably all know someone who lives and suffers with clinically significant levels of anxiety every day.

A variety of treatment options are available, from psychotherapy to psychopharmacological interventions. Anxiety is still being studied extensively, in order to further our knowledge and understanding, and to discover new treatment methods and options.

A couple of recent studies offer information on some relatively new developments.

One group of scientists chose to experiment on zebrafish due to brain similarities between zebrafish and mammals. Their research provides us with new information on the way in which anxiety is regulated in vertebrates, and shows how the normally functioning brain shuts down anxiety responses.

The team of scientists, led by Dr Suresh Jesuthasan from the A*STAR/Duke-NUS NRP, showed that disrupting a specific set of neurons in the habenula prevents normal response to stressful situations. In their experiments, Dr Jesuthasan’s team trained larval zebrafish to swim away from a light in order to avoid a mild electric shock. While normal fish easily learned this task, fish that had a specific set of neurons in the habenula damaged displayed signs of “helplessness.”

Although they initially tried to avoid the shock, they soon gave up. What’s more, these fish showed indications that they were more anxious than normal fish, such as being startled easily by non-harmful stimuli. Because of the similarity of the zebrafish brain to the mammalian brain, the study suggests that malfunction of the habenula is a possible cause of certain anxiety disorders in humans. This means that it may be possible to use direct stimulation of the habenula as a way of treating some types of anxiety disorders in humans. The zebrafish model which the scientists developed in the course of their work may also be used in future drug discovery efforts for psychiatric medicines.

Science Daily, emphasis added

In other developments, a new study indicates that researchers can turn a mouse’s anxiety response off or on by lighting up a connection in the brain.

The results, reported online March 9 in Nature, “gets us that much closer to understanding how the [anxiety] system works or how it doesn’t work in clinical cases,” says neuroscientist and psychiatrist Kerry Ressler, a Howard Hughes Medical Institute investigator at Emory University in Atlanta who was not involved in the study. The results, he says, will help researchers gain a deeper understanding of circuits in the human brain important for psychiatric disorders.

The new study focused on the amygdalae, a pair of structures buried deep within the brain, one on each side. These bundles of nerve cells are important for emotions, including fear, but it’s been less clear what role this brain region plays in anxiety, which unlike fear doesn’t require a specific trigger.

[. . .]

A particular connection – the place where cells in the basolateral part of the amygdala connect to the central amygdala – was the anxiety sweet spot, the researchers found. Normally, mice are afraid of wide-open spaces, where they could be nabbed by a cat or a bird. When given a choice in lab tests, mice spend most of the time hunkered down in a platform area with walls avoiding open areas. But when the connection between these two amygdala neighborhoods was boosted with a burst of light, mice quickly began exploring the formerly frightening areas. When the light was turned off, the mice retreated to the walled areas.

The opposite was also true, the team found. In another experiment, dampening the connection between the two amygdala regions made mice less likely to venture out from the walled areas. “It seems as though within the amygdala, there’s a real-time dial for turning down anxiety,” Deisseroth says.

Science News, emphasis added

Watch a video showing a mouse being tested in a maze before and after light stimulation to the amygdala here.

These are but two recent studies in the ongoing quest to better understand the phenomenon of anxiety. Hopefully in time what scientists have discovered here will have implications for and direct applications to human populations.  


2 comments

  1. for controlling anxiety. Studies have shown meditation increases activity in the prefrontal cortex and have a calming effect on the amygdala.

    You don’t have to become a Buddhist monk to learn relaxation techniques. Harvard Medical professor Dr. Herbert Benson published The Relaxation Response in 1975. The book demystified meditation and brought the benefits of deep breathing exercise to the general public. Massachusetts General Hospital has made the technique “A basic component in all of our programs, it is a key factor in mind body medicine.” http://www.massgeneral.org/bhi

    I used the Relaxation Response to develop my own deep breathing exercises. The key is to take slow, deep, diaphragmatic breaths. I can slow my breathing to three breaths per minute without effort. Ten minutes of such breathing is enough to bring even the worst anxiety under control.

    The technique is really easy to learn. Find someplace comfortable to sit where there will be minimal outside stimuli. Loosen any tight clothing. Focus on something across the room, I like a candle flame in a darkened room, or you can close your eyes. Breathe deeply using your diaphragm. If your abdomen is not expanding with each breath then you are not using your diaphragm.

    Each breath is done in four equal parts – in/pause/out/pause. When first starting, count slowly to three for each part. This will slow your breathing to five breaths per minute. As soon as you are comfortable with that rate you can increase the count to four or five. If desired, you can say a short phrase instead of counting, i.e. The Lord is my shepherd works well. If When a stray thought enters your mind simply concentrate on the numbers or words and on your breathing. Do this for 10-15 minutes.

    It helps to do some muscle relaxation when you first start. Tighten a group of muscles – feet, calves, thighs, hands, forearms, upper arms, back, neck, jaw – when you breathe in and then relax when you breathe out. I usually clench each muscle group for two or three breaths before relaxing them.

    That’s it. You don’t have to get on a plane and fly to India and study for years before getting the benefits of meditation. Do this routine for 15-20 minutes per day and you will see immediate benefits. Once you try it you’ll find yourself using the breathing techniques whenever you feel anxiety coming on. I have even used the deep breathing while my opponent is shooting during billiard tournaments. It keeps me calm and helps to eliminate missed shots caused by tension.

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