Exercise Helps Brain Become More Resilient To Stress

Physical exercise reorganizes the human brain so that it responds better to stress and normal brain function is less likely to be affected by anxiety, researchers from Princeton University wrote in the Journal of Neuroscience.

In an animal experiment, the authors found that when very physically active mice were exposed to a stressor - cold water - neurons in their brains that shut off excitement in the ventral hippocampus became much more active. The ventral hippocampus is a region in the brain that regulates anxiety.

This study may also resolve an inconsistency in research regarding the effect exercise has on the brain - namely that physical activity lowers anxiety while at the same time encouraging the growth of new neurons in the ventral hippocampus.

Exercise should, in theory, lead to more anxiety, not less, because these young neurons are typically more excitable than their older equivalents. However, this study found that physical activity also enhances the mechanisms that stop these neurons from firing.

Senior author, Elizabeth Gould, Princeton's Dorman T. Warren Professor of Psychology, explained that the effect physical exercise might have on the ventral hippocampus specifically has not been explored deeply. In this study, the team was able to isolate brain cells and regions that play key roles in the regulation of anxiety. They believe their findings may help researchers better understand and treat anxiety disorders.

From an evolutionary perspective, the study also showed how the brain can be surprisingly adaptive, tailoring its own processes to an organism's surroundings and lifestyle. Less physically fit creatures, for example, may benefit from a higher likelihood of anxious behavior. Gould said "Anxiety often manifests itself in avoidant behavior and avoiding potentially dangerous situations would increase the likelihood of survival, particularly for those less capable of responding with a 'fight or flight' reaction."

Professor Gould said:

"Understanding how the brain regulates anxious behavior gives us potential clues about helping people with anxiety disorders. It also tells us something about how the brain modifies itself to respond optimally to its own environment."

In this study, the mice were divided into two groups:

• The active group - all the mice had free access to a running wheel
• The sedentary group - there was no running wheel

Mice love running - give them a wheel and they will run about 2.5 miles (4 kilometers) every night. Six weeks later, the mice were exposed to brief periods of cold water.

Nearly as soon as they were exposed to the cold water (the stressor) the brains of the sedentary and active mice behaved differently:

• In the sedentary group, the cold water triggered an increase in "immediate early genes" - short-lived genes that are turned on rapidly when a neuron fires.
• In the active group these genes were not present, suggesting that their neurons did not immediately become super excited in response to the stressor.

The brain of an active mouse "showed every sign of controlling its reaction to an extent not observed in the brain of a sedentary mouse". Inhibitory neurons, which are known to keep excitable neurons in check, became much more active. Also, the neurons in the active mice's brains released more GABA (gamma-aminobutyric acid), a neurotransmitter that calms down neural excitement. There were higher levels of the protein that packages GABA into vesicles for release into the synapse in the active mice.

When the scientists blocked the GABA receptor that tamps down neural activity in the ventral hippocampus, the anxiety-reducing effect of physical exercise was canceled out.

In an Abstract in the journal, the researchers concluded:

"Together, these results suggest that running improves anxiety regulation by engaging local inhibitory mechanisms in the ventral hippocampus."

Exercise, even when forced, reduces anxiety and depressive symptoms

Even forced exercise reduces anxiety - physical activity helps relieve the symptoms of anxiety and depression whether you exercised because you wanted to or were forced to, researchers from the University of Colorado, Boulder, wrote in the European Journal of Neurosciences (February 2013 issue).

The authors explained that previous studies had demonstrated how exercise can help protect against stress-related disorders. However, nobody had looked into the effect forced exercise might have on anxiety. Examples of forced exercise may be seen among high school students, college and professional sportsmen and women, and military personnel.

Greenwood wondered "If exercise is forced, will it still produce mental health benefits? It's obvious that forced exercise will still produce peripheral physiological benefits. But will it produce benefits to anxiety and depression?"

The researchers designed an animal experiment using rats. They were divided into two groups, active and sedentary. The active group was further split into two, with one running whenever it wanted, and the other having to run on mechanized wheels that turned on at different speeds and for varying periods so that both active groups ended up doing the same amount of exercise.

Six weeks later the rats were exposed to a stressor and their anxiety levels were tested the following day.

They found that regardless of whether the rats were forced to run or chose to, the physically active rats were protected against stress and anxiety equally, compared to the sedentary rats.

Greenwood said "The implications are that humans who perceive exercise as being forced - perhaps including those who feel like they have to exercise for health reasons - are maybe still going to get the benefits in terms of reducing anxiety and depression.

A British study showed that regular intense physical exercise protects men from anxiety and depression for many years after they stop.

Written by Christian Nordqvist

Social Anxiety Disorder

A Glimpse of its Symptoms, Causes and Treatment

Social anxiety disorder is all about getting embarrassed and uncomfortable in front of other people due to an uncertain fear, the fear of being judged by the people. This is such a strong phobia that you may encounter it while doing your everyday routine work.

No doubt there is always some nervousness if you are going to deliver a speech in front of public, or meeting with new people, but what happens with people suffering from social anxiety disorder is that they start getting worried and nervous days before such things happen.

People with social anxiety disorder don’t even feel easy doing anything common if someone is watching them. They might get afraid of using a public washroom, or signing a cheque at a departmental store, or in bank, or they even may get afraid of drinking juice or cola at a public place. Some people face such problem only during certain situations or in some specific places, while the majority of them face this problem in all social circumstances. A person actually doesn’t have control most of the time to cover such problems, despite them knowing there is nothing to be afraid of.

Symptoms of social anxiety disorder

Social anxiety disorder has very clear symptoms. For example, the person tends to stay away from people or places, always in a fear of being judged by other people. They start fearing about any social meeting days before it happens, often finding difficulty in making friendships, They feel self-conscious and embarrassed in crowded place and might sometime feel nauseous when meeting with other people. People suffering from social anxiety disorder want to talk with other people, but most of the time they find it very difficult.

Unknown causes

Social anxiety disorder is common in families in some cases, but it is yet to be known why some people don’t have any such feelings while others are seriously disturbed. Researchers are working hard on finding the actual causes that results in social anxiety disorder.

Treatment methods

Commonly, for social anxiety disorder, there are two types of treatments in practice: medication, or counseling with a psychologist. Sometimes both treatment methods are used side by side. It has been observed that not all the treatment methods affect every patient, rather one individual might have a better outcome by using one method, while the other becomes fine by using the other treatment method.

Psychotherapy is considered to be a better treatment for most of the people suffering from social anxiety disorder. In psychotherapy, a person is told how they can come up against negative thoughts and start thinking positive about him. The method of cognitive behavioral therapy uses the idea that the person’s own thoughts and mindset determines how they should react or behave with others, while situations or meeting with people must not have any impact on their behavior.

This type of therapy is mostly used for counseling with people having social anxiety disorder. Sometimes a person is told to practice situations that induce anxiety upon them. This way a confidence is developed in their mind and they start to behave better in meeting others, or while talking to people.

There are several types of medicines that have been manufactured to assist in the treatment of social anxiety disorders. The medicines are referred by a consultant on the basis of the level of social anxiety disorder and the treatment method required.