Recurring depression shrinks the memory centre of the brain

Experiencing multiple episodes of depression can change your brain, according to new research conducted by Brain and Mind Research Institute at the University of Sydney.

Worryingly, the research showed people who have suffered multiple experiences of depression had a smaller hippocampus, the area of the brain involved in forming new memories.

The team, led by Ian Hickie, looked at brain scans and the medical history of almost 9000 people from the United States, Europe and Australia, 1700 had been diagnosed with major depression, the remainder had not experienced symptoms of depression.

The researchers noted that two thirds of those with major depression had suffered recurring symptoms and that these people’s brains had a smaller hippocampus that people who had experienced one bout of depression or none at all.

The study was unable to prove cause-and-effect between a smaller hippocampus and depression, but study authors say more research would explain if the brain changes are the result of chronic stress, or if these changes to the brain could help identify people who are more vulnerable to depression.

Associate professor Jim Lagopoulos, one of the researchers, says, “Despite intensive research aimed at identifying brain structures linked to depression in recent decades, our understanding of what causes depression is still rudimentary.”

The study, published in the journal Molecular Psychiatry, highlights the need to diagnose major depression before it can do damage to the brain.

For those who experience symptoms of depression it is therefore essential to secure a diagnosis. The findings of this study are particularly important for young people, although whether treatment of depression can prevent the shrinking of the hippocampus is not yet known.

Symptoms of depression include feeling overwhelmed, guilty, irritable, frustrated, unhappy or lacking in confidence. Physical indications range from being tired all the time, sick and run down, having a churning feeling in the gut, weight loss or gain and a loss of appetite. Someone who is depressed might not want to go out much, doesn’t get things done, withdraws from family and friends, may be using alcohol or sedatives, has no interest in doing fun things or trouble concentrating.

If you or someone you know is experiencing symptoms of depression, see your doctor or phone 1300 22 4636.