The Role of Functional Neuroimaging Techniques in Studying Brain Behavior

Since Psychology was emerging by the first psychologist, Sigmund Freud, psychologists just get more informations than just records from talk therapies. Neuroscientists developed several techniques to study brain behavior by measure their emotional and intellectual activity to understand people better through their brain to be able to further observation their physical behavior. They find a way to ensure it is safe to use on patients while obtains important informations they can find. The Neuroimaging techniques is use of different techniques to either indirectly or directly image the pharmacology, structure and function of the nervous system. They were mostly used as practice in neuroscience, medicine, and psychology field. The purpose of using the neuroimaging technique to help doctors and researchers to see the activity or problems in human's brain and get the diagnosis to identity the activity or problem.

There are six accepted and safe neuroimaging techniques to study brain behavior are using today in research facilities and hospitals all around the world. These six techniques were known as Functional Magnetic Resonance Imaging (fMRI), Computed Tomography (CT), Positron Emission Tomography (PET), electroencephalography (EEG), Magnetocencephalography (MEG) and Near Infrared Spectroscopy (NIRS). These Neuroimaging technologies will be explain what is their functional roles and how it benefits in understanding the brain behaviors. They are very important techniques that were used by neuroscientist who can identity mental illness or other disease and able to understand why the patient behaved the certain things. Each techniques will be explained their functional roles, advantages and disadvantages. The one of six Neuroimaging techniques was known as (fMRI) that measure the indirect consequences of the haemodyamic response. The procedure was that the patient has to lay on the movable examination table and go through the large cylindrical-shaped tube of an MRI scanner that contains powerful electro-magnet and stay for the certain time in between 10 to an hour depending on which part of your body.

For an example, the patient perform the MRI for bipolar manic and it was found that he has Bipolar disorder by discovering the colored stimulating neurons activity on the brain frontal lobe where Amygdala located. From the research article to the conclusion of detecting bipolar manic, Bipolar manic subjects exhibit blunted brain fMRI response to emotional cues throughout the ventrolateral prefrontal emotional arousal network. (Stephen M. Strakowski, MD, 2015) The neuroscientist can give the diagnosis of bipolar mania from the evidence he finds the disruption of the emotional network in the Amygdala that controls emotions that can be link to mood dysregulation. The beneficial of using fMRI is it doesn't require radiation which gives no risk to patients and able to evaluate their brain function safety and effective. There are few disadvantages of using fMRI was because it is very expensive. It only can capture a clear image of the brain only if the person stays still. The procedure of capturing the clear imagine usually take at least 30 minutes so it won't be good for a person who cannot stay still long. Since it is new, researchers today still don't fully understand how it works so it can be difficult to interpret the results. Another disadvantage example of using this tool was it comes with a lot of criteria that may not suit to certain patients.

People with the following implants cannot be scanned and should not enter the MRI scanning area: cochlear (ear) implant, some types of clips used for brain aneurysms, some types of metal coils placed within blood vessels,and nearly all cardiac defibrillators and pacemakers. (Radiation Therapy for Brain Cancer, 2018) This technique was known for patients to not use anything metal because this machine is magnet which can absorb everything, It is not safe for deaf patients who possess cochlear implant that contains magnet device in their skull. The cochlear isn't something they can remove without surgery so it may disrupt their brain study. The deaf patient with cochlear implantation will have to find alternative way if they try to find out if they have any kind of brain cancer.

And not only that, due to its high and most accurate technique, it is extremely expensive to the point that not many patients can afford to find their diagnose and seek the treatments earlier. So it also may be difficult for the researchers when it comes to understanding how bilingual may benefits the deaf patients linking to using cochlear implantation. The second of six technology was known as Computed Tomography (CT) is a medical imaging procedure that contains detailed pictures of structures inside the brain by using the X-rays. It can show the brain's features, but couldn't show its structure clearly. This article explained how CT scan works, "CT scan uses X-rays positioned at different angles to create cross-sectional images of the brain.

During a CT scan, a movable X-ray source is rotated around the patient's head" (NeuroImaging, 2014) This procedure allowed doctors and researchers to see the full view of the head and it provided more information about the brain than traditional X-ray scans, which only can do two-dimensional representation of the brain. It is painless, fast, and affordable. Comparing to other neuroimaging technologies, CT scan has more serious risks which made it a big disadvantage, despite to its advantages. The main risks associated with the use of CT scan, according to US Food Drug Administration are lifetime cancer risk will be increase because of x-ray radiation exposure, possible allergic reaction or kidney failure, and may need to get more follow up test after the abnormal result. Due to these serious risks had required for the patients to have a serious considering discussing with their doctor if this scan will be beneficial.

The third of six technologies, Positron Emission Tomography (PET) was developed because they couldn't detect more than just static images of the brain's structure in CT and fMRI. This technique was used to trace the amount of short lived radio material to map functional processes in the brain. The detector can pick up the radioactive decay a positron is emitted. They can detect the brain activity by looking at the areas of high radioactivity. Unlike other imaging test, PET can find irregularities in body function caused by disease which often happen before body structures changes become observable. "The quality of a PET scan is not affected by small movements, so the subject does not have to remain as still for a PET scan as they would for a FMRI or MRI scan, both of which can be ruined by small movements." (Neuroimaging, 2014)

This article showed that patients can be more comfortable with PET scan than fMRI without worry about delaying neuroscientist's evaluation if they made a small movement. The one of several disadvantages of using PET scan are its qualities and hospital bills. "It has poor spatial resolution so it won't be clear. Due to this, it is common for PET to be used together with CT or fMRI." (Neuroimaging, 2014) This means patients had to expect the high hospital bill coming to their home because combination two neuroimaging technologies are double expensive, just because PET couldn't provide the clear image because of low spatial resolution.

This is something patients should consider about when it comes to hospital bills. Not only that, PET scan comes with radiation so it will come with risk even if it only a small dose. The fourth of six techniques is Electronecephalography (EEG) is a noninvasive test that records electrical pattern in the patient's brain. It used approximately 20 to 128 small electrodes that places on the scalp to measure the electrical activity of the brain. The EEG machine amplifies these signals then records them in a wave pattern on graph paper. "The test is used to help diagnose conditions such as seizures, epilepsy, head injuries, dizziness, headaches, brain tumors and sleeping problems." (https://www.mayfieldclinic.com/) This technologies helps patients with seizures disorder to determine the type of seizure and origins of seizures. It is one of few best technique that has high temporal resolution when it comes to diagnosis these type of brain conditions.

Just like any other neuroimaging technologies, despite its ability to diagnose certain brain condition, EEG still have has big disadvantages. "One of the big disadvantages of EEG/ERP is that it's hard to figure out where in the brain the electrical activity is coming from." (https://www.ncilab.ca/erpeeg-2). When the electrodes were placed on the scalp, neuroscientist can get some idea of where the electrical signal are strongest components are strongest but it wont tell the location in the brain where the signals came from. But they can get better idea to see where signal comes from in same or different places if theres two ERP components. Since this is the best guess work so this technique requires more improvements. The fifth of six technique, Magnetoncephalography (MEG) is an imaging technique to measure the electrical activity that make magnetic fields in the brain with using very sensitive device that is known as SQUIDS. "There are many uses for the MEG, including assisting surgeons in localizing a pathology, assisting researchers in determining the function of various parts of the brain, neurofeedback, and others." (Demitri, 2016). "Unlike EEG, it doesn't require electrodes to be attached to the skin.

Instead, a person simply sits in a chair, resting their head inside the MEG helmet." (https://www.ncilab.ca/meg-2) This technology is more safer than EEG scan. This technique is very beneficial when it comes to assisting the surgeons and researchers when it comes to evaluate conditions like epilepsy by see which area that are stimulated to seizures. Despite how MEG may be less difficult being sit under the magnet, comparing to fMRI scan, MEG still had some disadvantages. "The main disadvantages of MEG are that it is more expensive and not as good as fMRI at localizing where precisely in the brain, activity is taking place." (https://www.sutherlandsurvey.com/Columns_Papers/Brain-imaging%20Methods.pdf) Simply, fMRI scan is better than MEG because fMRI is better tools when it comes to localizing where is the brain activity takes place in the brain. The last technology, Near infrared spectroscopy (NIRS) is the optical technique to measure the blood oxygenation in the brain.

The process of using NIRS laser was to chine the light in near infrared part of the spectrum (700-900) through the skill and find how much the remerging light is attenuated and how much it is depends on blood oxygenation. It also provides indirect measure of brain activity. This is especially used on patients with stroke and traumatic brain injury. Unlike any other Neuroimaging technologies, this comes with many advantages are more cheaper, smaller portable, involved with real human interactions, less sensitive to head motion and safe to any ages. NIRS lasers has several disadvantages. It has low spatial resolution which doesn't create a clear image. It can only record brain surface so doctors couldn't see whats inside of it. Theres also have no standard analyzing packaging and inaccurate activation localization. "NIR lasers often have beam qualities (e.g., beam width and divergence) which are not so well suited for microscopy.

The result is that spatial resolution can be somewhat compromised, and thus achievable results may not meet theoretical predictions." (https://www.horiba.com/us/en/scientific/products/raman-spectroscopy/raman-academy/raman-faqs/what-are-the-advantages-and-disadvantages-of-near-infra-red-nir-lasers-for-raman/) This technique can be invaluable sometimes so it won't be considered the best solution to every samples. Overall all these six Neuroimaging technologies' functional roles, advantages and disadvantages had been explained. After learning them, they are very extremely important tools in medicine, pathology, and psychology field.

Due to these disadvantages, there is an understanding why there aren't only one Neuroimaging technique to explore the human brain and able to obtain every answers doctors and researchers need to find due to lack of certain tools. But it is amazing that these Neuroimaging techniques able to help doctors and researchers to further their understanding the human brain and help other patient to get a certain treatments, especially when they were invented in less than approximately 100 years ago. Not surprised they all have similar disadvantages, the price. Even with these amazing techniques, everything in the world always has its disadvantages.

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