When people suffer from depression, they often become forgetful.

Scientists at the Brain and Mind Research Institute at the University of Sydney, Australia, reported in the journal Molecular Psychiatry that the hippocampus — a brain region that forms new memories — is significantly smaller in people who suffer from recurrent depression.

The investigators evaluated the brain scans and clinical data on about 1,700 patients with major depression and nearly 7,200 people without depression.

On average, the volume of the hippocampus in patients with recurring depression was significantly lower than other participants, including those who had only one episode of depression.

Although the study does not prove a cause and effect relationship between brain size and depression, it does point to the importance of proper diagnosis and treatment of depression as an important strategy to protect brain health.