November 27, 2007

High Stress Early in Life Changes Stress Response for Many Years Afterward

Stress has been identified as a potentially key factor in many cases of mental illness. A new research study suggests how early traumas and exposure to stress may result in a greater predisposition towards mental illness later in life. Researchers we have talked to have suggested that stress takes a toll on the mind and body, and its cumulative in nature - the more stress you experience or perceive, the more likely you are to have mental and physical health problems later in life. Researchers have also said that a single stressful incident is probably less harmful than long-term or ongoing situations involving moderate stress (for example growing up in a highly emotional and negative family, being subject to ongoing verbal abuse, or being stuck in a long term stressful relationship).

Researchers have known for years that psychological trauma that results in post-traumatic stress disorder (PTSD) or depression can change how a person responds to stress. Now, Cornell researchers report that rapes, sudden deaths of loved ones, life-threatening accidents and other such high-stress events (or examples of ongoing high levels of psycho-social stress) may result in long-term changes even if the survivor doesn't develop a clinical disorder immediately.

"The findings suggest that there may be persistent differences in the stress response in some trauma-exposed people, even if they do not exhibit PTSD or depression or both, and even if their trauma was years in the past," said Barbara Ganzel, Cornell M.S., Ph.D., a lecturer in human development in Cornell's College of Human Ecology.

Ganzel led a team of Cornell researchers, whose study is published in a special issue of the Journal of Traumatic Stress on the biology of trauma. They assessed a group of women before and after they took their medical admissions tests (MCATs), a stressful experience for most people. Measuring levels of a stress hormone in saliva (cortisol), they found that women who had experienced trauma earlier in life (but who did not have PTSD or major depression) had lower levels cortisol leading up to and after the MCAT exam.

In addition, they found that the women who had experienced trauma kept a negative mood after the test, compared with other women, whose moods lifted significantly after the exams.

Ganzel suspects that the stress response system in these women have compensated or changed over time. The trauma-exposed women showed lower rather than higher levels of cortisol, Ganzel theorized, because "stress initially boosts cortisol output but after the stressor is over, cortisol eventually falls below normal. These data suggest that, in some people, it may fall below normal and stay there, or that it develops a chronic tendency to dip lower than normal under stress."

Source: Journal of Traumatic Stress

Additional Related Information:

High Stress a Key Factor In Mental Illness

The Long-term Impact of Stress During Childhood on Brain Development

Lower level of Family Stress May Reduce Risk of Schizophrenia in Children

Blood Pressure Drug May be a Stress "Vaccine" for Mental Illness and Minimize Brain Damage

Mothers' Baby Cradling Habits a Sign of High Stress

Social Factors in the Development of Schizophrenia: A Review of Recent Findings

High Stress Jobs Increase Risk For Depression and Anxiety


So, according to this research, which uses medical/scientific vocabulary presented in an "objective" fashion, high stress provokes permanent changes in the patterns of people's response to stress, and these patterns translate, in biological terms, into low cortisol levels.
Many years ago, when psychoanalysts suggested that early object relations (mother/father/child, but particularly primary care giver and child) could have serious negative effects on a child's development, public opinion eventually revolted against the idea that families could somehow be responsible (not guilty, but responsible) for the mental illness of their loved ones. Question : just what could be more stressful that long term negative interaction with a primary care giver ? Any ideas ? Caution, I am not suggesting that such behavior is willful or voluntary, or that it can necessarily be controlled.

Posted by: Debbie at November 28, 2007 01:49 AM

Hi Debbie,

The research seems to show (see links in the article for details) that stress hormones that are damaging to the brain can be initially up-regulated (significantly increased) for the long term under extreme stress, or even ongoing moderate levels of stress. Moreover, the research shows that children's brains are much more responsive to stress - so what is only moderately stressful for an adult may be highly stressful for a child.

For example, research has shown that children raised in families with a lot of parental conflict tend to have raised stress hormone levels that can last for years afterward. These high levels of stress hormones (for long periods of time) are now believed by many researchers to be a key factor in risk for mental illness.

The research also suggests (specifically this research) that eventually (after years of high stress hormone levels) the area of the brain known as the HPA axis becomes seriously damaged and the stress response system becomes less responsive and the normal stress hormone response to stressful situations no longer functions and cortisol and glucocorticoid hormone production is lower than normal. In effect the stress hormone system gets "burnt out" from running at a high level for a long time.

At the same time there has been a significant amount of damage done to the HPA axis part of the brain - the Hypothalamus, the Pituitary and Adrenal glands. These areas of the brain are responsible for growth, emotional control, etc. I encourage you to click on the links in the above story to learn more about all the psycho-social factors that have been identified as increasing risk of mental illness.

The research that I've seen suggests that the following psycho-social factors might be key contributors to such stress in babies and children - they could be in the primary care environment or in school environments (for example, bullies at school):

Neglect (lack of attentive, loving care that soothes the child when they are upset)

Lack of caring human touch (research has shown that children who don't get much gentle, loving holding have raised stress hormone levels, and studies of rats have shown that rat pups that don't get much licking from their mother tend to have significantly higher levels of stress hormones and be prone to higher levels of anxiety - so this childcare/brain development/stress hormone link seems to be common to all mammals).

Lack of empathy for child emotional upsets

High levels of noise, judgment, criticism, or conflict in a household

Chaotic Family environment

High levels of tension and anxiety in the household

Poor communication in household

Frequent Intense, emotional emotional expression by parents and siblings

Flat emotional expression

Lack of humor and playfulness (excessive seriousness)

A negative mindset or negative outlook on life (i.e. one filled with worry and anxiety) has also been linked with higher stress hormone levels.

Again - all of this is covered in the links in the primary story above - and in the additional reading points also provided above.

Posted by: SzAdministrator at November 28, 2007 09:25 AM

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