Neuroimaging is the process of looking inside of the brain to see how it works. Click here to learn more about the uses and importance of neuroimaging!
Figure 1: A collection of images that contain multiple scans of a human brain
Introduction
In brain research, it is essential to understand how our brain is activated and how the different areas of our brain work. Ultimately, the main question of any experiment in the neuroscience field is on how to visualize brain activity. Unfortunately, neuroimaging is no trivial task, because nature, realizing the importance of the brain, has protected it as efficiently as possible: the brain is located under the cranium and placed in a certain fluid, which, like the adjacent tissues, protects it from external influences and damage. What’s good for nature is bad for neuroscientists, because the major question is: how do we look inside the brain when it is so protected?
Visualization of Brain Activity via Invasive Methods
The simplest method, which has long been mastered, is effective for the deceased brain: it is dissected, sections are made, and you can see the structure of neural connections on them. This is painstaking work: you need to sit down at the microscope and carefully, day after day, sketch the corresponding structures. One of the Nobel laureates, Santiago Ramon y Cajal, a Spanish neurophysiologist, was very fond of this method and received the Nobel Prize “for his work on the study of the structure of the nervous system”, during which certain principles of the brain were discovered. In addition, Ramon y Cajal is also known for his detailed sketches of neurons and cortices of the brain.
Figure 2: An example of Ramon y Cajal’s sketches (This specific one shows the various types of neurons located in the brain)
Non-Invasive Methods
Currently, the most popular method is functional magnetic resonance imaging (fMRI scans), which allows us to record the activity of the brain when solving a particular task. fMRI scans observe an area of the brain that is saturated with oxygen as a result of new blood flowing in. This is a mediated, indirect method of analyzing brain activity: By looking at which areas of the brain have a high and powerful blood flow, we know if those areas are active under a certain task or not. While fMRI scans have helped discover many hidden workings of the brain, they have one big drawback: this method is slow and does not allow us to see fast processes in the brain, since the process of blood supply is inertial.
Other Brain Imaging Technologies
Computed tomography of the head
Diffuse optical tomography
Optical signals modified by event
Magnetic resonance imaging
Functional magnetic resonance imaging
Magnetoencephalography
Positron emission tomography
Single photon emission computed tomography
Personal Opinion
I believe neuroimaging to be an incredibly important field of study that is oftentimes overlooked. There are a number of roles this particular area of study can play in science. One of them is identifying subtypes of depressive disorders and other mental illnesses.
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