By Rory Decker
From Mouse to Man to "Me Too": Bringing Science and Social Justice Together
Neuroscience is a very exciting field in the STEM world, especially for those interested in medicine or any sort of human-related field of study, as there are plenty of ways to research the human brain and potential brain-based diseases. Post-traumatic stress disorder (PTSD) is a fascinating disorder that is particularly relevant at this time because of current events surrounding sexual assault such as the “Me Too” movement. It should be well-known that many people that are survivors of sexual assault experience PTSD and other related issues. Survivors of sexual assault are impacted physically, emotionally, psychologically, and even biologically and neurologically. These impacts can be long-lasting, even permanent. Because of this, it is critical to understand the neurobiology and psychology tied to sexual assault, and that includes looking into how PTSD can affect survivors of sexual assault in a different way than it affects people who suffer from PTSD for other reasons.
Naomi Breslau, who passed away this year, was very important to the field of research surrounding PTSD. She was the first researcher to find that “interpersonal violence leads to higher rates of PTSD than other types of trauma” (“PTSD Researcher,” 2018). This is important information for those working with survivors of domestic assault and abuse. It also helps the general public understand what survivors of interpersonal violence go through, and understand why we need to take it seriously. This has led researchers to question whether (and how) something like sexual assault would impact the development of PTSD in a different way than other traumas.
PTSD is a disorder that is recognized by the DSM-5, a manual of mental disorders that can be used to help diagnose people with these disorders. It was not in the DSM, and therefore difficult to diagnose, until 1980 (Fenster, Lebois, Ressler, & Suh, 2018). Symptoms include intrusive re-experiencing of the trauma, avoidance, changes in mood, hindered cognition, differences in arousal and reactivity, and other symptoms (Fenster, Lebois, Ressler, & Suh, 2018). Comorbidity is common in those who suffer from PTSD, and this means that they can also suffer from disorders such as depression, anxiety, or have substance abuse problems (Fenster, Lebois, Ressler, & Suh, 2018). PTSD is debilitating and potentially deadly, as it can lead to suicide, especially if compounded by depression (Fenster, Lebois, Ressler, & Suh, 2018). Not all people who experience trauma develop PTSD. In fact, most people (50-85%) experience traumatic events, but not many develop lasting symptoms of PTSD (Fenster, Lebois, Ressler, & Suh, 2018). In general, 1.3-12.2% of a given population may be affected by PTSD (Fenster, Lebois, Ressler, & Suh, 2018), so it is not entirely uncommon.
Another important thing to note about PTSD, especially in relation to sexual assault, is that women who suffer trauma are more likely to remain silent about it (Fenster, Lebois, Ressler, & Suh, 2018). Women in general are more likely to develop PTSD, and in comparison to men, they tend to have more debilitating symptoms (Fenster, Lebois, Ressler, & Suh, 2018),* and considering that sexual assault impacts women more frequently (“Victims of Sexual Violence”), this could be a very important area to study. Even the types of symptoms of PTSD that women and men experience can vary.
Scientists are now thinking of PTSD in terms of circuits that are damaged or not functioning properly. In fMRI, or a functional magnetic resonance imaging, researchers are able to see what parts of the brain are being used to perform a certain task (“What is fMRI?”). This is shown by blood-oxygen-level-dependent (BoLD) signaling, which simply shows that oxygenated blood flows more to areas of the brain that are being used. In patients with PTSD, the connections that are shown during these tests are different than someone without PTSD, which suggests that the circuit has changed (Fenster, Lebois, Ressler, & Suh, 2018). For example, the ventromedial prefrontal cortex (associated with the extinction of fear that is learned by the amygdala), in those affected by PTSD, demonstrates altered circuiting (Fenster, Lebois, Ressler, & Suh, 2018).
Animal models like mice or rats have face validity, which means they share certain behavioral aspects of PTSD with humans, or in other words, it “looks” like they have the disorder, which means that if a treatment works on the animal, it might be just as effective in humans. Understanding the brain regions and circuits between them can help determine future treatment methods, or improve current ones. While not all survivors of sexual assault are affected by PTSD, there is no denying that improving treatment of it is a step in the right direction.
People are beginning to understand the weight of sexual assault in a survivor’s life, and how we can change that by being better researchers and looking in new directions. Naomi Breslau was one of the great researchers who paved the way for future research about PTSD, such as these researchers who looked at brain circuit dysfunction in relation to PTSD. I think these researchers are truly some of the best of 2018 because they are bridging the gaps not only between man and mouse that will lead to better researching of PTSD, but they are also indirectly helping uncover the relationship between sexual assault and PTSD, and how different traumas can change the development and symptoms of PTSD. Movements like “Me Too” are important in ending stigmas that surround sexual assault, but improving research to improve the lives of people post-assault is also incredibly important. For me, the best part of 2018 is being able to connect science and social justice.
*Please note that this discusses cisgender men and women
References:
Fenster, R. J., Lebois, L. A. M., Ressler, K. J., & Suh, J. (2018). Brain circuit dysfunction in post-traumatic stress disorder: from mouse to man. Nature Reviews. Neuroscience, 19(9), 535–551. https://doi.org/10.1038/s41583-018-0039-7
Taylor, Ashley P. (2018, November 15). PTSD Researcher Naomi Breslau Dies. Retrieved from: https://www.the-scientist.com/news-opinion/ptsd-researcher-naomi-breslau-dies-65099
Victims of Sexual Violence: Statistics. Retrieved from: https://www.rainn.org/statistics/victims-sexual-violence
What is fMRI? Retrieved from: http://fmri.ucsd.edu/Research/whatisfmri.html