Brain imaging reveals connection between dopamine levels and chronic depression in young women

A new brain imaging study led by researchers in the Department of Psychiatry and Behavioral Health in the Renaissance School of Medicine (RSOM) at Stony Brook University, and published in JAMA Network Open, uses a specialized type of magnetic resonance imaging (MRI) technique named neuromelanin-sensitive MRI to shed light on the link between chronic depression and the neurotransmitter dopamine. Dopamine plays important roles in many cognitive, emotional, and bodily functions and is a central cellular component to the reward/motivation system of the brain.

Some patients experience chronic depression, which is often debilitating and lasts for many years. The underlying factors that lead to chronic depression in some patients and briefer episodes in other patients are unclear. This study attempts to illustrate one possible method that may help clinicians understand why some depressions are chronic and some are brief.

The research team used this novel MRI technique to measure the neuromelanin signal in the midbrain of 105 women (mean age 21.6 years). In humans, neuromelanin accumulates slowly in the midbrain where the neurotransmitter dopamine is produced. The amount of neuromelanin signal detected by this MRI technique is directly related to lifetime dopamine production.

“We used MRI to measure lifetime accumulation of neuromelanin,” says Greg Perlman, Ph.D., lead author and Assistant Professor in the Department of Psychiatry and Behavioral Health. “We discovered that low neuromelanin MRI signal is related to chronic depression and less extraversion.”

Extraversion is a personality trait marked by enthusiasm, positive emotions, and sociability.

Perlman also points out that the “young women with briefer and less chronic depression had normal levels of neuromelanin MRI signal.”

Women in the study were evaluated for depressive disorders periodically by trained interviewers using the Diagnostic and Statistical Manual (DSM-IV), a leading source of classifying mental illnesses, starting at age 13–15-years-old and until the neuromelanin MRI scan at ages 20–24 years-old. The number of months of depression over these years was used to classify women into one of three groups: chronic depression, nonchronic depression, or no lifetime history of depression.

According to the National Institutes of Health (NIH) data on depression, (for 2021), approximately 21 million Americans have at least one major depressive episode each year. Among adults, the highest prevalence of a major depressive episode is in young adults, ages 18–25, at nearly 19%. And the prevalence of a major depressive episode is higher among women than men.

Perlman and his co-authors write that “the role of midbrain dopamine function in depression in general, and in chronic depression in particular, is poorly understood. Yet it is critically important to understand, given the magnitude of chronic depression’s public health burden and the need for novel therapeutic strategies.”

To help improve diagnosis and treatment of depression, the investigators will continue to study the link between depression and dopamine function in young adults, and as well as in teenagers. Perlman adds that the work may lead to more effective treatments and diagnosis for different subgroups of depression.