Research

Saliva holds clue to chronic bullying

University Park, Pa. -- Hormones in children's saliva may be a biological indicator of the trauma kids undergo when they are chronically bullied by peers, according to researchers who say biological markers can aid in the early recognition and intervention of long-term psychological effects on youth.

"Bullying is mainly self-reported either by students or observed by teachers," said JoLynn V. Carney, associate professor of counselor education at Penn State.

Carney and Richard Hazler, professor of counselor education at Penn State, looked at the hormone cortisol in students' saliva to evaluate its validity as a reliable biomarker in assessing effects of precursors to bullying. They worked with Douglas Granger, professor of biobehavioral health and human development and family studies; Leah Hibel, doctoral student in biobehavioral health; and Insoo Oh, doctoral student in counselor education.

In humans, this hormone is responsible for regulating various behavioral traits, such as the fight-flight response and immune activity that are connected to sensory acuity and aspects of learning and memory.

"A lot of kids suffer in silence. When you hear of school shootings, or students who commit suicide as reaction to chronic peer abuse, those are kids who are not coping with the abuse by seeking appropriate support," said Carney. "They keep their anger and frustration within and fantasize either how they are going to escape the abuse through suicide or how they are going to get revenge on their abusers."

When a person senses a threat, the cortisol level spikes and learning and memory functions are negatively impacted, Carney said. The body basically focuses the bulk of its attention on surviving the threat. The longer such a spike continues, the more damage it can do to various aspects of a person's physical, social and emotional health. However, when a person undergoes a lengthy period of stress similar to the chronic bullying experience, researchers have found less than normal cortisol reactions that are related to a decreased sensitivity to stress, a sort of numbing or desensitizing effect.

This hypocortisol finding, Hazler noted, has serious physical and psychological implications for kids -- both victim and bystander. Research with adults exposed to repeated stressful events has linked hypocortisol with conditions such as chronic fatigue syndrome, chronic pelvic pain and post traumatic stress disorder (PTSD).

The Penn State researchers tested the saliva of 94 sixth-grade students between ages 9-14, along with a questionnaire on their experience on being bullied or watching someone being bullied, and additional measures of anxiety and trauma.

Since cortisol has a predictable daily pattern of highest levels in early morning and declining levels throughout the day, researchers collected samples of saliva when the students first arrived at school and then again before lunch.

"Lunchtime is one of those less supervised periods when kids are more likely to be bullied. One of the things we are trying to measure is not the reaction immediately following a bullying event, but instead the anticipatory anxiety that takes place with the approach of situations where bullying is more commonly occurs. Even kids who are not bullied suffer from such anticipatory stress because they anticipate watching their friends getting bullied and worry that they might be next," said Hazler.

"It is this anxiety that we believe is most dangerous because that anxiety stays with you. It is not dependent on the bullying happening on a continual basis," he added.

Results from the study suggest that while bullying is directly linked to trauma and anxiety, it is indirectly linked to cortisol levels.

"This confirms our theory that while exposure to a one-time or very rare bullying episode might cause higher cortisol levels, exposure to bullying on a chronic basis would be associated with hypocortisol levels," said Carney and Hazler, who recently presented their findings at the American Counseling Association Convention in Detroit.

The Penn State researchers liken their research on bullying to the study of depression, which used to be solely about psychiatric observations and behavioral tests until researchers began to find biological changes.

"All of a sudden depression was not simply a psychological phenomenon, but it also has a physical aspect with potential medication treatments to support counseling," they noted.

Last Updated March 31, 2010

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