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Post 7- Final Paper Ideas

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For my final paper, I have decided to write about the effect of PTSD on stress (HPA axis, glucocorticoids), genetics (epigenetics), drug effects and the individual differences that exists as a result of the mental health condition. Additionally, the essential clinical applications of the disorder from the use of animal model to its influence on human patients will be examined. The five literature sources that I have found so far explain different aspects of PTSD and its biological and behavioural significance.
Firstly, Zoladz et al (2011) aimed to investigate whether in the form of a psychosocial stress paradigm) exhibited long-term memory of the stressor after exposure to psychosocial stress, and whether glucocorticoid levels were altered afterwards.  They found that post cat exposure (the stressor), there was an increase in anxiety and cardiovascular reactivity, and a decrease in cognition and glucocorticoid levels. The findings allow for further understanding of the biological effects after a psychologically traumatic event. Following the same path of glucocorticoid receptors, Daskalakis et al (2014), looked at individual differences in the response to PTSD but in relation to glucocorticoids as well as traumatic stress versus exposure.  As discussed in many class sessions, the difference in sexes does have distinct effects on behaviour. Daskalakis et al considers this alteration and investigate behavioural measures in vulnerable or resilient phenotypes in relation to PTSD. Since PTSD is variable at the individual level, it is important to also consider how the disorder differs between sexes.
In 2005, Zhang et al wished to further investigate the molecular mechanisms underlying PTSD. Considering the year of its publication, more research would be necessary to specifically satisfy their conclusions. Moreover, in 2013 the researchers Raabe et al studied how epigenetic programming influenced PTSD development since it was dependent on genetic variation. They claim that although more research is yet needed in knowing whether experience influences the genetics, the experience-dependent epigenetic programing of stress genes is important in de-regulating stress systems.
Like many of the studies we have read in this class, drugs do have effect on behaviours and disorders, including PTSD. Xu and colleagues wished to investigate the effect that the drug estrazolam has on PTSD symptoms. They administered rats with estrazolam and found that the drug had anti-PTSD effects on the animals. In other words, the anxiety-like behaviors were ameliorated by estrazolam, and this drug was also associated with the biosynthesis of allopregnalone. Thus, it can be indicated that specific drugs also influence effects of PTSD, but need to be taken with caution as the disorder varies drastically between individuals. This is a potential way in the direction of improving PTSD symptoms in patients. 
Overall, these five papers will be the basis for the discussion of PTSD and the effects that it has on behaviour in animal models but also to clinical applications in human medicine. 

Links to papers:
https://www.ncbi.nlm.nih.gov/pubmed/22421563
https://www.ncbi.nlm.nih.gov/pubmed/25114262
https://www.ncbi.nlm.nih.gov/pubmed/16216432
https://www.ncbi.nlm.nih.gov/pubmed/23966957
https://www.ncbi.nlm.nih.gov/pubmed/30195748

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