Inflammation attacks brain's reward center

February 2, 2016, Elsevier
brain
Credit: public domain

A new study by Neil Harrison and colleagues published in Biological Psychiatry suggests that a brain reward center, the striatum, may be directly affected by inflammation and that striatal change is related to the emergence of illness behaviors.   

Inflammation increases the risk for .

More specifically, inflammation induces behavioral changes similar to depression that are often associated with illness, including , difficulty concentrating, lack of motivation, and reduced experience of pleasure.  

The authors recruited 23 patients with hepatitis C who were beginning treatment with interferon-alpha (INF-α). This treatment provokes an immediate inflammatory response, confirmed by measuring cytokines in the blood.  

Four hours after INF-α administration, a specialized type of imaging, called magnetization transfer imaging, was performed that showed evidence of microstructural changes in the when compared to scans conducted prior to INF-α administration. This suggests that the striatum is highly sensitive to IFN-α.  

IFN-α also induced fatigue and depression in the patients, particularly over weeks 4 through 12 of treatment. Interestingly, the early striatal structural change predicted the later emergence of fatigue, but not depression, in the study participants.  

Changes in the striatum were heterogeneous with some changes associated with the risk for fatigue, while other changes seemed to be protective against developing fatigue.  

"Inflammation-related fatigue and depression are big clinical problems," said Dr. John Krystal, Editor of Biological Psychiatry. "This study highlights that the brain regions central to reward and motivation are directly altered by inflammation in ways that that appear to predispose or protect against developing fatigue but not depression. The heterogeneous striatal response may suggest that fatigue and mood are supported by different microcircuits within the striatum."  

"These findings are important as they show that a relatively simple MRI technique can be used to measure effects of inflammation on the brain," Harrison commented. "Inflammation is increasingly implicated in the cause of common mental illnesses, particularly depression. This technique could be a powerful way to identify patients who are most sensitive to effects of on the brain. It could also be used to monitor response to novel anti-inflammatory therapies that are now being tested in depression."

Explore further: Inflammation linked to weakened reward circuits in depression

More information: Nicholas G. Dowell et al. Acute Changes in Striatal Microstructure Predict the Development of Interferon-Alpha Induced Fatigue, Biological Psychiatry (2016). DOI: 10.1016/j.biopsych.2015.05.015

Related Stories

Inflammation linked to weakened reward circuits in depression

November 20, 2015
About one third of people with depression have high levels of inflammation markers in their blood. New research indicates that persistent inflammation affects the brain in ways that are connected with stubborn symptoms of ...

Inflammation markers could guide depression treatments

January 12, 2016
Psychiatrists investigating depression have been energized in recent years by reports of rapid, successful treatment with drugs that interfere with the brain chemical glutamate, such as the anesthetic ketamine.

Uncovering the source of inflammatory malaise

October 22, 2012
(Medical Xpress)—A study conducted by researchers at Emory indicates that inflammation targets a part of the brain called the basal ganglia, causing symptoms of depression and fatigue. The study was recently reported in ...

New biological evidence reveals link between brain inflammation and major depression

January 28, 2015
A new study by the Centre for Addiction and Mental Health (CAMH) found that the measure of brain inflammation in people who were experiencing clinical depression was increased by 30 per cent. The findings, published today ...

Early life stress and adolescent depression linked to impaired development of reward circuits

October 29, 2015
Early life stress is a major risk factor for later episodes of depression. In fact, adults who are abused or neglected as children are almost twice as likely to experience depression.

Brain imaging reveals clues about chronic fatigue syndrome

May 23, 2014
A brain imaging study shows that patients with chronic fatigue syndrome may have reduced responses, compared with healthy controls, in a region of the brain connected with fatigue. The findings suggest that chronic fatigue ...

Recommended for you

Millennial men value altruism and self-care above traditional male qualities

April 25, 2018
Contrary to popular stereotypes, young men today are likely to be selfless, socially engaged and health-conscious, according to a new study from the University of British Columbia and Intensions Consulting, a Vancouver-based ...

Indications of psychosis appear in cortical folding

April 25, 2018
Imaging techniques can be used to detect the development of psychosis in the brains of high-risk patients at an early stage, as reported by researchers from the University of Basel and Western University in the journal JAMA ...

Maternal binge drinking linked to mood problems and alcohol abuse in offspring

April 25, 2018
Binge drinking by pregnant and lactating mothers can impair the mental health of their offspring, reports a study published today in Frontiers in Psychiatry. In a rat model, Italian researchers find that while habitual drinking ...

Engaging in physical activity decreases people's chance of developing depression

April 24, 2018
An international team including researchers from King's College London have found physical activity can protect against the emergence of depression, regardless of age and geographical region.

Imagining a positive outcome biases subsequent memories

April 24, 2018
Imagining that a future event will go well may lead you to remember it more positively after it's over, according to findings from research published in Psychological Science, a journal of the Association for Psychological ...

Early childhood interventions show mixed results on child development

April 24, 2018
Early childhood interventions may have some efficacy in boosting measures of child health and development in low income countries, but more work is needed to sort out how to implement these interventions, according to a new ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.