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Functional Magnetic Resonance Imaging also known as fMRI, is a breakthrough imaging modality, which works as an effective tool for analyzing and demonstrating regional changes in the brain (Glover, 2011; James, et al, 2014). Since its introduction in 1990, fMRI has revolutionized studies in the fields of neurosciences, and clinical psychology and psychiatry (Glover, 2011). The non-invasive nature of the method; along with the precision with which it tracks functional responses made by the brain through Blood Oxygen Level Dependent (BOLD) contrast, has been the main reasons for its widespread popularity amongst said studies (Glover, 2011; James, et al, 2014). It is researcher, Seiji Ogawa, that fMRI owes this discovery; as Ogawa, built on the foundation of magnetic resonance imaging by introducing BOLD – as a contribution to the structural mapping provided by Magnetic Resonance Imaging (MRI) (James, et al, 2014; Seiji Ogawa, 2017). The BOLD effect, relying on the difference in the magnetic properties of deoxyhemoglobin and oxyhemoglobin (dHb) to generate a brain map corresponding to blood flow to active neurons (Glover, 2011; James, et al, 2014). The basic idea here, being; when a task is performed, neuronal activity increases in that specific part of the brain corresponding with the task – with enhanced neuronal activity being metabolically taxing- leading to a local increase in oxygen and energy consumption within the designated functional brain area (Brains On Trial, 2013; James, et al, 2014).. This in turn, results in regional cerebral blood flow (rCBF) and regional cerebral blood volume(rCBV) increase. The extra demand for blood flow in the active neuron, leads to more oxygenated hemoglobin appearing in the venous capillaries (James, et al, 2014). According to James et al, (2014) this then shifts the way in which deoxygenated and oxygenated hemoglobin relate. It is the concentration changes in dHb, that BOLD contrast relies on. The concentration variations for which, leads to a change in the signal intensity of MRI. The effect for which can be reviewed in the fMRI BOLD contrast images, as illustrated in appendix……. (James, et al, 2014). .     

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