The human brain is a complex organ, so complex, in fact, that science is just beginning to unlock some of its mysteries. Science does know that the brain is divided into many different regions, each with different responsibilities that they control. One area, the prefrontal cortex is responsible for the regulation of emotions, self control as well as physical factors including the blood pressure and the blood sugar. According to a new study, led by a Yale neurobiologist, Rajita Sinha, chronic, major stress can cause the brain to shrink over time, especially in the prefrontal cortex.

Sinha's study showed that major stress, such as what is felt when there is a major, life changing event, including the death of a family member or a job loss coupled with a history of feeling stressed over other types of situations can cause brain shrinkage all over the brain but that the highest amount of that loss is in that one, important area. That shrinkage can lead to an increased risk for both psychological and physical disorders including high blood pressure and anxiety. Damage to this area of the brain can also allow for overeating and other health damaging behaviors.

Stress has always been a factor to human life, but in the few decades, the number of stress factors have skyrocketed along with a number of other conditions including obesity, high blood pressure, diabetes and others. While science has worked to connect those conditions to changes in food products and eating habits, it might be the increased number of these conditions could just as easily be explained by the higher instance of stress.

Most studies that focus on stress and its connection to the brain's health have been done with people who have already been diagnosed with psychological disorders or other health problems. Sinha has said that studies done with healthy people and stress are rare, at best.

Sinha's study looked at 103 people, all listed as healthy at the start of the study, between the ages of 18 and 48. Each of the participants were asked for information about their stress levels as well as major stress causing events in their life. They were also asked to rate how they felt about those events and how they typically handled their feelings surrounding them. Finally, the participants were asked to have MRI scans at the start of the study and again at the end to measure any sign of brain shrinkage or loss of blood volume.