Understanding "why" a condition occurs is often the most difficult question to answer. Although we already have a good grasp of the characteristics and treatment of social anxiety disorder, our present understanding of social anxiety disorder is incomplete.
Multiple causes are suspected, especially a combination of genetic makeup, early growth and development, and later life experience. Current theories are grouped into the following categories:
Just as physical features such as hair and eye color are inherited, sensitivity to criticism or social scrutiny may be passed on from one generation to the next. It's possible that the child of one or two shy parents may inherit genetic code that amplifies shyness into social anxiety disorder.
Through his research at Harvard University, Jerome Kagan, Ph.D., found evidence of this genetic predisposition. He studied children from infancy through early adolescence. He found 10-15% of children to be irritable infants who become shy, fearful and behaviorally inhibited as toddlers, and then remain cautious, quiet and introverted in their early grade school years. In adolescence, they had a much higher than expected rate of social anxiety disorder.
Kagan also found a physiological accompaniment of anxious temperament in these children: a high resting heart rate. Their resting heart rates rose even higher in the presence of mild stresses. Additionally, when exposed to new situations, these children exhibited substantial behavioral restraint — becoming quiet, avoiding interaction and even retreating from the scene. Parents of these children have increased rates of social anxiety disorder and other anxiety disorders.
"Fear of two staring eyes is widespread throughout the animal kingdom." With this declaration, Professor Isaac Marks begins the marvelous section on "being looked at" in Fears, Phobias, and Rituals (Oxford University Press, New York, 1987), his book on anxiety disorders. He cites animal studies in which birds were found to avoid prey associated with, or which had markings similar to, the vertebrate eye. In some cases the presence of an "eye-like" image (like the moth in the photo here) caused them to escape. Even in the animal kingdom, being under another's scrutiny is uncomfortable!
These eyespots drove away yellow buntings in an experiment. When the eyespots were rubbed off, the moths were more likely to be eaten.
Dr. Marks goes on to state:
"Although staring can be a threatening behavior, it does not always frighten humans. Ordinarily, staring arouses and engages the person being stared at, but the context decides what sort of engagement that is. Lovers enjoy looking into one another's eyes. In the right context, staring increases another person's helpfulness. For example, if a woman carrying a load of packages stands on a street corner and stares at a pedestrian who is waiting to cross, that pedestrian will cross faster than one who is not stared at. But if she drops a package and stares, the pedestrian is likely to approach, pick up the package, and hand it to her. The fallen package makes the engaging stare appealing rather than threatening."
"When the context of a stare is neutral or ambiguous, it can be unsettling and provoke escape. In one experiment, a bystander either stared at drivers who stopped at a red light or gave them a quick glance of civil inattention. When the traffic light changed, drivers who had been stared at pulled away faster than those who had merely been glanced at did."
Averting the gaze is common in people with social anxiety disorder. Though exact cues and reinforcements for these behaviors must vary widely, their role in the development and maintenance of social anxiety seems significant.
Social anxiety emerges at different developmental stages. Babies develop a fear of strangers at seven months, not before. Separation anxiety is quite clear in some children—perhaps more obvious in three-year-olds we take to daycare than in five-year-olds going off to kindergarten. Being alone is difficult for children ages six to eight, but actually becomes desirable as they approach puberty and adolescence. Solitude becomes more important as anxiety about physical appearance and performance in school increases. We also know that traumatic or stressful life events occurring at an early developmental stage may increase the risk of social anxiety disorder.
The exact workings of the brain and its biochemistry in normal versus pathological anxiety states have not been fully defined. We believe that both normal anxiety and abnormal anxiety are probably created by the same set of brain structures, neurotransmitters (chemical messengers) or neuromodulators (chemical regulators). Examples of brain regulation include control of thinking, control of physiologic functions, and control of behaviors. For example, thoughts can range from safe to dangerous, serious to humorous, etc. Physiologic functions, such as regulation of blood flow, the nervous system and the muscular system, fluctuate from resting states to initial arousal, then to marked arousal/anxiety and finally to extreme anxiety or panic. Behaviors from deep sleep to moderate activity to extremes of fighting, fleeing or freezing are all played out endlessly in each of us.
It is probable, although not certain, that at least four brain areas are critical to our anxiety-response system:
| the brain stem (cardiovascular and respiratory functions) |
| limbic system (mood and anxiety) |
| prefrontal cortex (appraisals of risk and danger) |
| motor cortex (control of muscles) |
These structures are richly supplied with three major neurotransmitters: norepinephrine (NE), found in neurons arising primarily from a part of the brain stem called the locus ceruleus; serotonin (5-HT), found in neurons beginning in the raphe nuclei of the midbrain; and gamma aminobutyric acid (GABA), found in neurons that are widespread throughout the brain. Other neurotransmitters and neuromodulators, including corticotropin releasing factor (CRF) and cholesystokinin, probably play important roles in the regulation of arousal and anxiety.
Individuals with social anxiety disorder (and other anxiety disorders) probably have abnormalities in the functioning of some parts of their anxiety response system.
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