Neuroimagery is a clinical speciality that produces images of the brain by using non-invasive techniques, i.e.: without requiring surgery, incision of the skin, or any direct contact with the inside of the body. This type of imagery falls into two categories: Structural; this deals with the structure of the brain and aids the diagnosis of diseases (e.g. brain tumours) and Functional; this is used for neurological and cognitive research purposes, along with the diagnosis of metabolic diseases (e.g. Alzheimer’s and Parkinson’s). Neuroimagery enables us to directly visualize the processing of information by the centres of the brain. This processing causes the involved area of the brain to increase metabolism and as a result highlight itself on the screen in a prominent colour.
The first neuroimaging technique was known as the “Human Circulation Balance”, which was invented by Angelo Masso in the 1880’s. This method of neuroimagery was able to measure the redistribution of blood during emotional and intellectual activity using the non-invasive techniques outlined above. There have been significant changes in technology since this, including the introduction of Magnetic Resonance Imaging scans (MRI) in the 1970’s and Computed Axial Tomography scans (CT) in the 1980’s. From these methods of neuroimagery came Magneto encephalography (MEG), Position Emission Tomography (PET), Electroencephalography (EEG) and Functional Magnetic Resonance Imagery (fMRI).
The advances in technology of neuroimagery have enabled us to see what parts of the brain are stimulated when carrying out certain tasks. For example, Schon et all discovered that when reading music, a tiny spot at the back of the head (known as the right superior parietal cortex) becomes active (2000). This has led to numerous discoveries into cognitive processes in the brain, and has also inspired research of abnormal brain development. The fMRI scan has played a major role in this type of research and it is on such that this essay will be based.
Functional magnetic resonance imagery (fMRI) uses MRI technology to measure brain activity by detecting relevant changes in blood flow. The process can also give us information on the structure and function of the brain, unlike other processes which can only provide us with one of these two. fMRI scanning relies on cerebral blood flow (CBF – blood supply to the brain at a given time) and neuronal activation are coupled – meaning that when an area of the brain is in use, the blood flow in that region increases. fMRI scans take pictures of the brain every few seconds over a period of several minutes to help researchers determine results of a scan. While fMRI scans cannot detect absolute activity of brain regions, it can detect differences between different conditions. Therefore, a patient will be asked to perform tasks or will be stimulated to trigger processes or emotions during their scan.
The primary form of an fMRI scan uses Blood-Oxygen-Level dependent...