Early Life Stresses and Other Areas of Focus
Early Life Stresses
In animals, researchers are studying how stress, especially when it occurs in early life, affects how adverse events are handled later in life. Rat pups who are subjected to the stress of being separated from their mothers for several minutes early in life have, months later, a much greater startle reaction to a stressful event than pups who were never separated. This line of anxiety research may help scientists learn how genes and experience affect who is vulnerable and who is resistant to anxiety disorders.
Another area of research on anxiety has led to the discovery that anxiety disorders are associated with abnormal levels of certain hormones. People with post-traumatic stress disorder (PTSD), for example, tend to be low on the stress hormone cortisol, but have an overabundance of epinephrine and norepinephrine, which could be why they continue to feel anxious after the trauma. In addition, they tend to have higher-than-usual levels of corticotropin releasing factor (CRF), which switches on the stress response and may explain why people with PTSD startle so easily. Scientists are researching ways to correct hormonal imbalances and bring the PTSD symptoms under control.
Current studies using imaging tools allow researchers to monitor the living brain and watch the amygdala, the cortex, and other areas of the brain at work. They can identify abnormal activity when a person has an anxiety disorder and determine if medication or cognitive and behavioral therapies help to correct it.
Recent studies of the brain using magnetic resonance imaging (MRI) showed that people with OCD had significantly less white matter than did control subjects, suggesting a widely distributed brain abnormality in OCD.
Imaging studies are also looking at how brain structure may be related to PTSD. A part of the brain involved in emotion, called the hippocampus, tends to be smaller in some people with PTSD. Researchers are trying to decipher whether that is a result of extreme stress responses related to the trauma, or whether people who already have a smaller hippocampus are more prone to PTSD.