Posttraumatic stress disorder

Neurocircuitry models of PTSD have focused on the interactions between the AMYG and the medial prefrontal cortex and hippocampus. Hypersensitivity and lack of habituation to repetitive nonthreatening stimuli characteristic of PTSD may be a result of decreased regulation of AMYG activity by the anterior cingulate cortex suggesting an impairment of processes mediating extinction to trauma-related stimuli, as well as decreased hippocampal function, implying an impaired ability to form appropriate contextual associations and dysfunctional memory processing with respect to trauma-related stimuli. mMRI studies of PSTD have focused primarily on the hippocampus. Reduced hippocampal volumes in Vietnam combat veterans have been reported and studies in adults with either childhood or adult traumatic experiences also support an association between reduced hippocampal volume and PTSD. Studies in pediatric populations, however, have failed to show reductions in hippocampal volumes, suggesting that this decrease may develop over time. It is also possible that smaller hippocampal volumes may be a risk factor for developing PTSD, rather than a consequence of the trauma.17 Functional imaging studies using a neutral state paradigm have shown increased regional cerebral blood flow in the caudate and putamen, as well as the orbitofrontal and anterior cingulate cortices. Several studies of PTSD using symptom provocation paradigms have shown increased activity in the AMYG and a lack of involvement of the anterior cingulate cortex.18 Studies examining responses in a working memory task suggest patients with PTSD have a distinct pattern of brain activation in response to the organization and processing of verbal working memory, relying more heavily on nonverbal working memory and shifting away from verbal processing.

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Blood Pressure Health

Blood Pressure Health

Your heart pumps blood throughout your body using a network of tubing called arteries and capillaries which return the blood back to your heart via your veins. Blood pressure is the force of the blood pushing against the walls of your arteries as your heart beats.Learn more...

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