A long-term study has found that persistent bullying can cause enough psychological trauma to inflict lasting damage on the developing brain.
The study was part of IMAGEN, a European research project that aims to study how biological, psychological and environmental factors influence brain development in adolescents.
These findings were drawn from a long-term study on teenage brain development and mental health which utilized both brain scans and mental health questionnaires. 682 teenagers between the ages of 14 and 19 from England, Ireland, France and Germany were studied. Researchers tallied 36 teenagers in total who reported experiencing bullying persistent enough to be considered chronic.
When researchers compared the brains of these participants to individuals who had experienced less intense bullying, they found that their brains looked different. It was found that certain regions of the brains of participants who had experienced chronic bullying had shrunk in size.
This pattern of shrinking was most notable in two parts of the brain called the putamen and the caudate. These are changes which are highly reminiscent of adults who have experienced early life stress, such as childhood abuse or maltreatment. The researchers said that to an extent, they could explain these changes through the obvious links between bullying and higher levels of general anxiety.
Changes in brain volume as well as the levels of depression, anxiety and hyperactivity at age 19 were taken into account.
“Although not classically considered relevant to anxiety, the importance of structural changes in the putamen and caudate to the development of anxiety most likely lies in their contribution to related behaviours such as reward sensitivity, motivation, conditioning, attention, and emotional processing,” explained lead author Erin Burke Quinlan from King’s College London.
Previous studies have shown links between childhood bullying and mental illness in adulthood. A study published in JAMA Psychiatry in 2015 for example, showed that children who are bullied in early childhood are at increased risk of depressive disorders. However, the recent study is the first to show that ceaseless victimization could actually result in the physical reshaping of the brain. The study’s authors have stated that this is cause for serious concern because the teenage years are crucial for healthy mental development, as during this time the brain is expanding at an incredible pace.
According to the study, the pruning of some of this growth is normal. However, chronic bullying can lead to the pruning process spiralling out of control and causing potentially irreversible damage. The researchers also suspect that as these individuals age, they may experience even greater shrinkage in the brain.
The study has been published in Molecular Psychiatry.