![brain scan eeg brain scan eeg](http://static.guim.co.uk/sys-images/Guardian/Pix/pictures/2011/7/10/1310320623514/MRI-scan-and-EEG-007.jpg)
The advantages of NIRS are portability, ease of use and that it is cheap. Also, NIRS temporal resolution is similar to MRI, since we are obtaining similar information, that is, changes in blood flow. NIRS can only get information from cortical tissues, since NIR light is fully absorbed in deeper regions of the brain. It happens that when a particular area of the brain is active, its oxygen demand increases and thus haemoglobin concentration also increases. That way the transmission and absorption rate of the NIR light in human tissues can be obtained, which contains information of the changes in haemoglobin concentration. The idea is to attach a source of NIR light to the scalp and an NIR light detector. This is a relatively recent technique: medical and physiological applications have only been developed in the last few decades.
BRAIN SCAN EEG PORTABLE
Also, MRI equipment is very expensive, bulky and thus not portable and unsuitable for out-of-the lab use. The drawback is the temporal resolution, which is quite low (higher than 1 second). MRI has great spatial resolution (2-3 mm), which makes it very suitable for both research and clinical applications. These photons are then measured by the MRI and a map of a living tissue can be generated. Very briefly, MRI uses strong magnetic fields and electromagnetic pulses to excite protons which then generate a photon before decaying to their normal state. Paul Lauterbur and Peter Mansfield, pioneers in MRI techniques received the Nobel prize for medicine in 2003. MRI is a relatively new technique (the first MRI image was published in 1973). It represents the Holy Grail in brain imaging techniques as well as for medical imaging in general. On the other hand, the spatial resolution of EEG is higher than other brain imaging techniques (about 1-2 cm). With this technique we can make a 3D map of the interior of the brain, just by measuring the electrical potentials in the scalp of the brain.ĮEG is cheap, non-invasive, relatively easy to set-up and the time resolution is excellent: down to less than 1 ms or, in other words, lower than the time needed to have an action potential. Complex EEG data analysis techniques have been developed (a brief overview can be found here), such as the so-called EEG-tomography. EEG interpretation and data analysis techniques have also advanced a long way. EEG devices have advanced greatly since then, making them more reliable, more portable, with more electrodes and even wireless. Hans Berger recorded the first EEG of a human in 1924. In this post we will go through the 4 most awesome of these techniques EEG recorded by Hans Berger (Public Domain) Electroencephalography (EEG)ĮEG could be considered the father of neuroimaging techniques, since it is the first technique used to measure (electrical) activity of the living brain. These advances have been made possible thanks to the different brain imaging techniques discovered during this last century. Brain science has made huge advances in the past decades, and our understanding of the b rain, far from being complete, has increased enormously.