The Effects of Rewards on Depression

Major depressive disorder affects approximately 15 million adults in the U.S. each year. It is also considered on of the leading causes of disability between the ages 15 to 45. According to the National Institute of Mental Health, depression is a mood disorder that affects how you think, feel, and handle daily activities. There are many causes of why depression occur such as, family history, major life changes, trauma, stress, or even medications.

Dr. Stewart Shankman, professor at University of Illinois at Chicago, spoke at Loyola University Chicago about his study on how individuals with panic disorder and major depressive disorder reacted to either threat or reward. In his study, individual’s with panic disorder were shown threatening stimuli and those with major depressive disorder were observed in their response to reward. The results found presented that individuals with panic disorder showed a higher sensitivity to stressful events, while those with major depressive disorder were associated with abnormal frontal EEG asymmetry while anticipating rewards. From his findings he concluded that there is a correlation between individuals with panic disorder and depression and how they approach stressful or rewarding situations.

In a similar study done by Roberto Malinow, professor at University of California, he found that people with major depressive disorder show an increased sensitivity to negative information. Malinow studied the lateral habenula which is rooted deep in the brain. Neurons of this region are in an excitatory state due to negative events, these events can range from punishment to absence of an anticipated reward. With more research, it is evident that this area of the brain is a key part of the “disappointment circuit.” The lateral habenula lacks what the brain uses to reduce over activity such the excitatory neurotransmitter glutamate and inhibitory neurotransmitter GABA. Malinow and his colleagues found that, “the balance of chemicals released controls the processing of negative events and that this balance can be shifted by drugs.”

With these findings, neuroscientists can find potential antidepressants to act on the pathways more selectively and correct the negative bias in depression.

Works Cited

Makin, Simon. "Depression Tweaks the Brain's Disappointment Circuit." Scientific American. N.p., 1 Jan. 2015. Web. 4 Mar. 2016. <http://www.scientificamerican.com/article/depression-tweaks-the-brain-s-disappointment-circuit/>.

Shankman, Stewart A., Brady D. Nelson, Casey Sarapas, E. Jenna Robison-Andrew, Miranda L. Campbell, Sarah E. Altman, Sarah Kate Mcgowan, Andrea C. Katz, and Stephanie M. Gorka. "A Psychophysiological Investigation of Threat and Reward Sensitivity in Individuals with Panic Disorder And/or Major Depressive Disorder."Journal of Abnormal Psychology 122.2 (2013): 322-38. Web.

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