THE DORSAL COLUMN individuals’ shifting diet & cortisol were the result of uprooting and moving elsewhere. In CAH493’s case, the shift in nutrition was not consistent with starvation or diet overhaul, but with an immune response, which is typical when the body attempts to fight things like the flu. Cortisol is also a potent suppressor of the immune system, and CAH493’s mounting cortisol response was likely a result of heightened immune signals in the hypothalamus. In other words, the brain was releasing cortisol as an attempt to slow down the immune response. Other individuals experienced an elevation in cortisol levels at specific points, independent of changes in diet. Webb et al. propose this is likely the result of violence or another psychological stressor present in this person’s life shortly before death. Recently, the Van Uum lab collaborated on a hair-cortisol study regarding current-day youths exposed to high levels of trauma. In their study “Hair cortisol concentrations in war-affected adolescents: A prospective intervention trial” Rana Dajani and colleagues sampled hair cortisol from Jordanian and Syrian youths. They found that individuals that presented high levels of insecurity expressed high levels of cortisol. Those exposed to multiple traumas displayed abnormal cortisol levels, indicative of a breakdown of proper stress responses. Importantly, following an intervention, the researchers found a normalization of cortisol levels for all participants. These findings underline the importance of mental health interventions in erasing or reducing the potential harm that long-term high cortisol levels may leave on the body.
VOLUME 1 // ISSUE 1 Overall, the discussed study highlights a novel method of reconstructing a timeline of stress. Since this study was published, other researchers have investigated timeline reconstruction. For example, a 2019 study replicated the Peruvian technique in Egyptian mummies dated to 50-450CE. Moreover, a 2017 study reconstructed stress timelines in whales by analyzing their baleen, which is a part of their filter-feeding system that is similar in composition to human hair . These studies give us insight into how stress and diet are reflected throughout the body and give us a fascinating look into how science can reconstruct portraits of people’s lives from microscopic remnants of the past.
MAJOR ASSUMPTION OF fMRI LIKELY CORRECT BY NICHOLAS HANDFIELD- JONES
Functional Magnetic Resonance Imaging, more commonly known as fMRI, has revolutionized the way researchers study the brain. By using a magnet that is tens of thousands times stronger than the Earth’s magnetic field, scientists can peer into the deep recesses of the brain and see how it works.
Despite its widespread use, the interpretation of fMRI data relies on assumptions, some of which remain untested. Recently, researchers at Western University have shown that one important assumption in modern fMRI analysis is
SOCIETY OF NEUROSCIENCE GRADUATE STUDENTS
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