The part of the brain that controls emotions and memories, the hippocampus, actually shrinks in people who have depression that is recurrent and improperly treated, according to a global study.
These findings highlight the notion that it’s very important to treat depression as early as possible. This is particularly true for teenagers and young adults.
This depression study involved 15 research institutes from around the world, including Australia, the United States and Europe, who collaborated to compile the results from smaller studies. These studies compared the hippocampuses of depressed people with those who did not suffer from depression. The research allowed medical professionals to examine the magnetic resonance imaging data in the brains of 8,927 people. Of these people, 1, 728 people had major depression; the rest of the subjects were healthy.
Researchers discovered that 65 percent of the people who were depressed had recurrent depression. These individuals also had a smaller hippocampus. The hippocampus is in the middle of the brain, and is also involved with long-term memory, as well as forming new memories and associating emotions with these memories.
The brain and mind research institute at the University of Sydney headed the Australian portion of the study. Professor Ian Hickie was the co-director, and stated that the people in the study who were having their first episode of depression had a hippocampus that was of normal size. He shared that the more depressive episodes the person had, the small the hippocampus became. Hickie concludes that “…recurrent or persistent depression does more harm to the hippocampus the more you leave it untreated. This largely settles the question of what comes first: the small hippocampus or the depression? The damage to the brain comes from recurrent illness.”
Dr. Hickie is also a national mental health commissioner, and shared that identifying and treating depression in the right ways at the onset of the disease is vital when it comes to preventing hippocampus damage. He reiterates that treatment is especially important for young adults and teenagers who are suffering from depression.
Professor Hickie also stated that damage to the hippocampus is reversible. The professors explains that other studies have demonstrated that the damage can be repaired and “the hippocampus is one of the unique areas of the brain that rapidly generates new connections between cells, and what [is lost] are connections between cells rather than the cells themselves.”
He also states that medications are not the sole remedy for treating depression. He shares that people who are unemployed or having nothing productive to do all day can sit in a room without engaging in activity and the hippocampus would shrink. Social interactions are essential to depression treatment and natural supplements like fish oil are recommended for neuro-protection.
However, Hickie also indicated that antidepressants could have a protective effect on the brain since the hippocampuses of people taking medication for depression were larger than those who were not being treated.The professor stated that this information could prove to dispel some of the negative opinions associated with antidepressant medication.
Still, Professor Hickie asserted that medication shouldn’t be the only treatment, and that psychotherapy should be the first line of treatment for young people who have depression.
Jim Lagopoulos, the study’s co-author, stated that the findings from the study provided important insight into the way the brain is structured. He also shared that the research could help medical professionals understand which mechanisms in the brain are responsible for depression.
Lagopoulos confirmed that the accuracy of the findings was due to collaboration. He states that, “despite intensive research aimed at identifying brain structures linked to depression in recent decades, our understanding of what causes depression is still rudimentary.”
One reason for the lack of understanding, according to Lagopoulos, is the lack of large studies surrounding depression and brain activity, as well as the variations in treatment, brain structure and degrees of depression.
The findings, which came from the largest international study comparing brain volumes in people who have and do not have major depression, was published in Molecular Psychiatry.