In a new study by researchers at The University of Texas Health Science Center at Houston (UTHealth) , damage to the hippocampus–the brain’s seahorse-shaped center for mood and memory–was linked to bipolar disorder. This study is groundbreaking; it’s one of the first to link volume decreases in specific parts of the hippocampus to bipolar, something scientists have been trying to answer.
Different subfields of the hippocampus may have different functions and may be affected differently by mood disorders like depression or anxiety disorders. The researchers at UTHealth used magnetic resonance imaging (MRI) and segmentation approaches–which includes the delineation of brain features using image contrasts–to discover differences in the volumes of subfields of the hippocampus. Patients with bipolar disorder were compared to healthy controls as well as patients with major depressive disorder.
The study found that people who suffer from bipolar disorder had reduced volumes in subfield 4 of the cornu ammonis (CA) of the hippocampus. In patients with bipolar I disorder, the reduction was even more severe. Also, as the illness went on, the volumes of areas such as the right CA 1 decreased. People who had manic episodes had even more reduced volumes in the hippocampal tail and other CA areas.
The researchers hope that the study will be able to encourage more research pinpointing the details of the hippocampus as it relates to bipolar disorder, thus creating better treatments for the disease.