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NAME : Malathi Sundra Saigaran (BBA00069)
Balakrishnan Nair Gunasaharan (BCS00078)
Vijayasakaraan Punusamy (BBA00087)
PROGRAMME : Bachelor of Business Administration (HONS)
Bachelor of Computer Science (Hons)
INTAKE : September 2011
SUBJECT CODE &TITLE :
UNI 1204 Understanding Human Behaviors
QUESTION NO. : 3
LECTURER : Dr. Choong Lean Keow
DATE OFSUBMISSION :
18 June 2012
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Tittle page
Question number 3
Examine some of the most important technologies that have allowed scientist to peer into the
workings and structure of the living human brain. What are the advantages and disadvantages
of each of these technologies?
Group members
Malathi Sundra Saigaran
Balakrishnan Nair Gunasaharan
Vijayasakaraan Punusamy
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Contents Page number
1.0 INTRODUCTION 5
2.0 BRIEFLY ABOUT BRAIN 5
2.1 The Brain 5
2.2 Why pyschology is important in technologies 6
2.3 Brain Disease 6
3.0 AIM OF THE PAPER 7
3.1 The MRI 7
3.1.1 How does an MRI Scanner Work? 7
3.1.2 What does an MRI Scan Show? 8
3.1.3 How does an MRI Scan Differ from a CT Scan? 9
3.1.4 Advantages of MRI10
3.1.5 Disadvantages of MRI10
3.1.6 Overall of MRI11
3.2 The PET/CT Scan 12 3.2.1 What is PET/CT? 12
3.2.2 Expectation before PET/CT scan exam? 13
3.2.3 Preparation for PET/CT Exam? 14
3.2.4 Advantages of PET/CT 15
3.2.5 Disadvantages of PET/CT 16
3.2.6 Overall of PET/CT 17
3.3 THE ELECTROENCEPHALOGRAPHY (EEG) 18
3.3.1 EEG recording techniques 20
3.3.2 Advantages and Disadvantages of EEG 23
3.3.3 Overall of EEG 24
4.0 CONCLUSION 24
5.0 REFERENCEError! Bookmark not defined.
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Figure 1 : Brain 5
Figure 2 : The four lobes 6
Figure 3 : MRI with label 7
Figure 4 : Example of stroke brain CT vs. MRI 9
Figure 5 : PET/CT 12
Figure 6 : Example of brain stroke image detect by PET/CT 14
Figure 7 : The EEG 18
Figure 8 : The set of EEG equipment 20
Figure 9 : Different function of the brain 21
Table 1 : Summaries of advantages and disadvantages of MRI11
Table 2 : Summaries of advantages and disadvantages of PET/CT 17
Table 3 : Summaries of advantages and disadvantages of EEG 24
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1.0 INTRODUCTION
This paper attempt to discuss about the most important technologies that have
allowed scientists to peer into the workings and structure of the living human brain . In this
paper we, also had go through the advantages and disadvantages of each technologies. First
of all , here an explanation about the living human brain. The type of disease in living human
brain and the he types of most important technologies.
2.0 BRIEFLY ABOUT BRAIN
2.1 The Brain
Figure 1 : Brain
The human brain is not only one of the most important organs in the human body; it is
also the most complex. Instead, the goal of this brain tour is to familiarize you with major
brain structures and their functions.
The cerebral cortex is the part of the brain that functions to make human beings unique.
Distinctly human traits including higher thought, language and human consciousness as well
as the ability to think, reason and imagine all originate in the cerebral cortex.
The cerebral cortex is what we see when we look at the brain. It is the outermost
portion that can be divided into the four lobes of the brain.
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Figure 2 : The four lobes
(Hess, 2008)
2.2 Why pyschology is important in technologies?
Can think about the machines that they can produce to reduce the brain diseases. It
slightly like pyscologist can persume the patients with any stronger depresse. They can
conduct the patient slowly to the way that can cure or to produce any skill machines to
distinguish the brain.
2.3 Brain Diseases
When the brain is healthy it functions quickly and automatically. However, when
problems occur, the results can be devastating. Some of the major types of disorders include:
TYPES EXAMPLES
Neurogenesis diseases Huntingtons disease and muscular dystrophy
Developmental disorders cerebral palsy
Degenerative diseases Parkinsons disease and Alzheimers disease
Metabolic diseases Gauchers disease
Cerebrovascular diseases stroke and vascular dementia
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Trauma Spinal cord and head injury
Convulsive disorders epilepsy
Infectious diseases AIDS dementia
Brain tumours
3.0 AIM OF THE PAPER
3.1 The MRI
Figure 3: MRI with label
MRI stands for Magnetic Reasoning Imaging. It is a fairly new technique that has
been used since the beginning of the 1980s.
MRI is commonly used to diagnose and follow the progress of such conditions as
Alzheimers, strokes, meningitis, and brain tumours.
The MRI scan uses magnetic and radio waves, it does not expose to the radiation.
Magnetic resonance imaging (MRI) is a test that uses a magnetic field and pulses of
radio wave energy to take pictures of the head. In many cases, MRI gives information that
cannot be seen on a ray, ultrasound, or computed tomography (CT) scan.
3.1.1 How does an MRI Scanner Work?
The patient lies inside a large, cylinder-shaped magnet.
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Radio waves 10,000 to 30,000 times stronger than the magnetic field of the earth are
then sent through the body. This affects the body's atoms, forcing the nuclei into a different
position.
As they move back into place they send out radio waves of their own.
The scanner picks up these signals and a computer turns them into a picture. These
pictures are based on the location and strength of the incoming signals.
Our body consists mainly of water, and water contains hydrogen atoms. For this reason,
the nucleus of the hydrogen atom is often used to create an MRI scan in the manner.
3.1.2 What does an MRI Scan Show?
Using an MRI scanner, it is possible to make pictures of almost all the tissue in the
body.
The tissue that has the least hydrogen atoms (such as bones) turns out dark, while the
tissue that has many hydrogen atoms (such as fatty tissue) looks much brighter.
By changing the timing of the radio wave pulses it is possible to gain information about
the different types of tissues that are present.
An MRI scan is also able to provide clear pictures of parts of the body that are
surrounded by bone tissue, so the technique is useful when examining the brain and spinal
cord.
Because the MRI scans gives very detailed pictures it is the best technique when it
comes to finding tumours (benign or malignant abnormal growths) in the brain. If a tumour is
present the scan can also be used to find out if it has spread into nearby brain tissue.
The technique also allows us to focus on other details in the brain. For example, it
makes it possible to see the strands of abnormal tissue that occur if someone has multiple
sclerosis and it is possible to see changes occurring when there is bleeding in the brain, or
find out if the brain tissue has suffered lack of oxygen after a stroke.
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The MRI scan is also able to show both the heart and the large blood vessels in the
surrounding tissue. This makes it possible to detect heart defects that have been building up
since birth, as well as changes in the thickness of the muscles around the heart following a
heart attack. The method can also be used to examine the joints, spine and sometimes the soft
parts of your body such as the liver, kidneys and spleen.
3.1.3 How does an MRI Scan Differ from a CT scan?
With an MRI scan it is possible to take pictures from almost every angle, whereas a CT
scan only shows pictures horizontally. There is no ionizing radiation (X-rays) involved in
producing an MRI scan. MRI scans are generally more detailed, too. The difference between
normal and abnormal tissue is often clearer on the MRI scan than on the CT scan.
Figure 4: Example of stroke brain CT vs. MRI
URL: http://www.housemd-guide.com/house 1
LEFT: Unenhanced (labelled -) and contrast -enhanced (labelled +) images from CT (top
row) and MRI (bottom row) in two different patients with brain tumours. Contrast enhanced
http://www.netdoctor.co.uk/hearthealth/examinations/ctgeneral.htmhttp://www.netdoctor.co.uk/hearthealth/examinations/ctgeneral.htmhttp://www.netdoctor.co.uk/hearthealth/examinations/ctgeneral.htmhttp://www.netdoctor.co.uk/hearthealth/examinations/ctgeneral.htm -
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images show both normal blood vessels (red arrows) and tumour enhancement from
breakdown of the blood-brain barrier (yellow arrows).
3.1.4 Advantages of MRI There are no known dangers or side effects connected to an MRI scan. The test is not
painful; you cannot feel it. MRI systems do not use ionizing radiation as MRI contrast
materials have a very low incidence of side effects, the procedure can be repeated without
problems.
Some advantages of MRI include diagnosing strokes in their earliest stages; diagnosing
MS (multiple sclerosis); diagnosing brain and pituitary tumours; diagnosing brain, spine, or
joint infections; visualizing torn ligaments in the wrist, knee, and ankle (sports player use
MRIs); visualizing shoulder injuries; diagnosing tendonitis; evaluating soft tissue masses; and
evaluating bone tumours, cysts, and herniated discs in the spine.
Another advantage of a MRI is its ability to image in any plane. CT scans are limited to
one plane, the axial plane. An MRI system can create axial images.
3.1.5 Disadvantages of MRI
People with pacemakers cannot have MRIs. Also some people who are morbidly obese
cannot fit in into an MRI system. Claustrophobic patients cannot usually make it through a
MRI. The machine makes a tremendous amount of noise during a scan. The noise sounds like
a continual, rapid hammering. Patients are given earplugs or stereo headphones to muffle the
noise (in most MRI centres you can even bring your own cassette or CD to listen to). The
noise is due to the rising electrical current in the wires of the gradient magnets being opposed
by the main magnetic field. The stronger the main field, the louder the gradient noise.
There is a small theoretical risk to the foetus in the first 12 weeks of pregnancy, and
therefore scans are not performed on pregnant women during this time, because patients have
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to lie inside a large cylinder while the scans are being made some people get claustrophobic
during the test.
MRI scans require patients to hold still for extended periods of time. MRI exams can
range in length from 20 minutes to 90 minutes or more. Even very slight movement of the
part being scanned can cause distorted images which means the scanning will need to be
repeated. Orthopaedic hardware (screws, plates, artificial joints) in the area of a scan can
cause severe distortions on the images. MRI systems are very expensive; therefore the exams
are also very expensive.
3.1.6 Overall of MRI
MRI use magnetic and radio waves.
It is not expose to radiation.
MRI scan every angle of our human brain
The table shows the summarise of advantages and disadvantages of MRI
Table 1 : Summaries of advantages and disadvantages of MRI
Advantages Disadvantages
Not painfull
No radiation
Can repeat
Diagonising stroke in earliest stage
Ability image in any place
Can create axial image
People with pacemaker cannot have
MRI
Morbility obese cannot fit
Claustrophobic patients cannot
usually use MRI
Tremendous noise
Risk for 12 months pregnancy
Hold till for long periods takes 20-90
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minutes
Orthopaedic hardware can cause
severe distortions on the images
are very expensive
3.2 The PET/CT Scan
3.2.1 What is PET/CT?
Figure 5 : PET/CT
PET stands for Position Emission Tomography. It is a test that detects the changes in
the body on a cellular level. Since cellular changes take place before physical ones do, PET
can help your doctor make an earlier diagnosis or determine if your current treatment is
working effectively. This unique function makes a PET scan extremely valuable in measuring
and detecting cancerous growths and tumours in the brain.
CT stands for Computerized Tomography. When combined with a CT scan, the end
result is extremely detailed. A CT scan uses X-rays to provide a picture of the inside of the
body. This makes locating tumours and abnormalities in the body much easier. By combining
the two images (the PET scan and CT scan) a doctor receives an even fuller and more
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complete picture than when using just one or the other independently of each other. This
ensures more accurate diagnoses can be made and more effective treatment given.
3.2.2 Expectation before PET/CT scan exam?
Before the scan, you will be injected with a radioactive tracer. The tracer is a compound
similar to sugar. You will be asked to rest for 60 minutes while the tracer is distributed
through your body.
The technologist will ask you to lie down on the scanner table, which will slowly pass
through the scanner. The PET scanner detects and records the signals given off by the tracer.
The signals are then put together into actual images through computer processing.
The radiologist will read the images and contact your primary care doctor. Your doctor will
discuss the results with you.
Example of a patient undergoes PET that written on his blog:
Today is the day Ive been waiting for the second to the last step in becoming a
survivor. I am having my PET scan hmmmm? Otherwise known as Positron
Emission Tomography uhhh, even more confusing! Basically, they inject a glucose-
based radiopharmaceutical (uhhh, still more confusion) but lets call it glow -in-the-dark
nuclear dye, let it travel through my body, and then they take digital pictures. This
procedure is much like a CT scan, but super sensitive. It sees cells instead of masses, and
can detect dead or live cancer cells in their early stages, as well as heart disease. These are
the 2 things the oncologist is checking for. Apparently, a major side effect of my chemo
cocktail is heart disease lovely!
Source: (coconutwirelessss, 2010)
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Figure 6 : Example of brain stroke image detect by PET/CT
Source: (health, 2012) 1
3.2.3 Preparation for PET/CT Exam?
No food during the six hours before your exam Eat a light dinner the night before your exam
Drink only water the day of your exam, preferably 16-24 ounces of water before the
exam
Do not have any caffeine this includes tea, coffee, etc.
No chewing gum
No chewing tobacco
Take any prescribed medications on the day of your exam, unless otherwise instructed
by your doctor
Shower the night before your exam, not the day of your exam
Do not exercise stay calm, quiet and relaxed
Wear comfortable clothes
Leave all valuables at home
Review patient exam preparation instructions
Arrive 30 minutes prior to your exam
No family members are allowed in with you during the exam
This figure 7 shows the CT scans showing how it looks:
i. Ischemic stroke on the right side of the pictureii. Haemorrhagic stroke, you can see blood on the right
side of the picture
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3.2.4 Advantages of PET/CT
There are a number of benefits of a PET CT scan.
i. The exam is painless. The PET scan can provide detailed information about any
abnormal cells - in this respect it can detect abnormal cells, the speed at which they are
developing and how much they have spread. The information that is produced in this way is
completely unique, and would be out of reach otherwise.
ii. There is no other scan or combination of scans that can provide as detailed and full a
picture as that of a PET CT scan. Using imaging software and scans in this way is a much
cheaper alternative than carrying out surgery to look into the body.
iii. Sometimes an investigative surgery will be unavoidable, but this is usually a last
resort as it is more time consuming, more expensive and a great deal more difficult for the
patient who may takes days or even weeks to recover.
iv. A PET CT scan can be carried out on an outpatient basis so it provides the minimum
inconvenience to the patient. PET scanning in particular, regardless of whether or not it is
combined with a CT scan, provides intricate details of the body on a cellular level. This
allows a disease or illness to be detected very early on, more so than other modalities are able
to provide.
v. When combined however, a PET scan and CT scan are extremely accurate. They can
be performed at the same time; the patient does not even have to change positions which
mean there is very little room for error. This also makes it one of the most convenient
medical imaging methods available.
vi. Software developed for reading data from a PET-CT allows for the metabolic (PET)
and Anatomical (CT) data to be aligned one on top of the other giving the radiologists the
most complete information possible.
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3.2.5 Disadvantages of PET/CT
Positron emission tomography (PET) scans work by injecting a patient with a radionuclide
(known as a "tracer"), which can be detected by the large scanning machine. Computers
locate the concentrations of the tracer compound in the body, and recreate a three-
dimensional image of the area for doctors to examine. Though PET scans are mostly safe and
are a useful diagnostic tool, there are a few disadvantages associated with their use.
i. Radioactivity - Though the amount of radiation absorbed by the body when the
radionuclide tracer is injected is relatively low, it may be dangerous to patients who are
sensitive to the radiation. Patients, who are pregnant, may become pregnant or are breast
feeding should generally avoid PET scans. Additionally, because the radioactivity persists in
the body for a length of time, patients should avoid contact with sensitive persons, such as
anyone who is pregnant, elderly or suffers from decreased immunity for several hours after
the procedure.
ii. Cost - PET scanning machinery is expensive for a hospital to obtain and susceptible to
breaking down. As a result, hospitals bill patients a large sum of money when they use the
machines. Patients who require a PET scan should expect to be charged between $900 and
$1400 for the scan as of 2010, though this amount may be covered partially or in full by your
insurance carrier. Additionally, the costs associated with PET scanning machinery means that
not all hospitals have machines available to use.
iii. Spatial Resolution - PET scans have a relatively low spatial resolution when
compared with other types of scanning procedures. This means that very small abnormalities-
-such as that less than 1 mm may be difficult to distinguish from blurs caused by the
movement of the patient. Additionally, the limits on the amount of radionuclide tracer that
can be safely injected into the body makes it difficult to clearly render the body's tissues. This
means that certain abnormalities can be missed, or that false positives can be made.
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iv. Discomfort - The tracer takes between 30 and 60 minutes to reach the appropriate area
in the body, and the scanning process takes between 45 and 60 minutes. Patients with limited
mobility or difficulty remaining still for long periods of time may find the PET scan process
uncomfortable or impossible to perform
3.2.6 Overall of PET/CT
A PET/CT scan combines both technologies into one machine. It provides:
A picture of cellular function (PET)
A picture of physical structure (CT)
A merged picture of the bodys cellular function and physi cal structure
Table 2 : Summaries of advantages and disadvantages of PET/CT
Advantages Disadvantages
The exam is painless and safe.
Provides earlier detection of recurrent
cancer.
Tells the difference between non-
malignant (benign) and malignant
tumours.
Reduces invasive procedures and
multiple tests.
Avoids unnecessary surgery.
Accurately assesses the location and
stage of the malignant disease.
Locates previously unknown
Explode to radioactive
Pregnant women unsuitable
cost expensive
hard to detect small abnormalities
discomfort
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metastases.
Reduces the time to diagnosis and
leads to earlier treatment.
3.3 THE ELECTROENCEPHALOGRAPHY (EEG)
The language of communication with the nervous system is electric. EEG is a tool for
measuring electrical activity generated in the brain, which opens a window for exploring
neutral activity and brain functioning. The EEG signal is measured using electrodes placed on
the scalp, which record the electrical field generated by the nerve cells.
People with epilepsy will often have abnormal electrical activity seen on this test. In
some cases, the test may show the area in the brain where the seizures start. The brain may
appear normal after a seizure or between seizures.
According to R. Bickford on research and clinical applications of the EEG in humans
and animals are used to:
(1) monitor alertness, coma and brain death
(2) locate areas of damage following head injury, stroke, tumour, etc
(3) test afferent pathways (by evoked potentials)
Electroencephalography(EEG)
Figure 7 : The EEG
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(4) monitor cognitive engagement (alpha rhythm)
(5) produce biofeedback situations, alpha, etc
(6) control anaesthe sia depth (servo anaesthesia)
(7) investigate epilepsy and locate seizure origin
(8) test epilepsy drug effects
(9) assist in experimental cortical excision of epileptic focus
(10) monitor human and animal brain development
(11) test drugs for convulsive effects;
(12) investigate sleep disorder and physiology
Electroencehalography belongs to electrobiological imaging tools widely used in
medical and research areas. EEG measures changes in electric potentials caused by a large
number of electric dipoles formed during neural excitations. EEG signal consists of different
brain waves reflecting brain electrical activity according to electrode placements and
functioning in the adjacent brain regions. For using EEG techniques, the following recording
system components are necessary:
Electrode cap with conductive jelly or Ag-AgCl disc electrodes with conductive paste.
Amplifiers with overall amplification gain between 100-100,000, with input
impedances at least 100 MOhms, and common-mode rejection ratio at least 100 dB.
Analog filters integrated in the unit with high pass filter with cut-off frequency in the
range of 0.1-0.7 Hz and low pass filter with cut-off frequency less than one half of the
sampling rate. In fact, frequencies above 50 Hz are rarely involved as they contribute
negligibly to power spectrum of EEG.
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At least 12 bit A/D converter with accuracy lower than overall noise (0.3-2 V pp.),
and sampling frequency usually between 128 1024 Hz.
Sufficiently quick PC for taking over data for recording and eventually for online
analysis, with adequate volume of hard disc.
Digital high pass FIR filter with similar cut-off frequency as analog high pass.
The general quality of recording equipment depends on the right combination of the
mentioned parameters. Before further data processing, raw EEG signal should be checked for
artefacts.
3.3.1 EEG recording techniques
Encephalographic measurements employ recording system consisting of
o electrodes with conductive media
o amplifiers with filters
o A/D converter
o recording device
Electrodes read the signal from the head surface, amplifiers bring the microvolt signals
into the range where they can be digitalized accurately, converter changes signals from
analog to digital form, and personal computer (or other relevant device) stores and displays
obtained data. A set of the equipment is shown in Figure 8.
Figure 8 : The set of EEG equipment
: Amplifier unit, electrode cap, conductive jelly, injection, and aid for disinfection.
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Scalp recordings of neuronal activity in the brain, identified as the EEG, allow
measurement of potential changes over time in basic electric circuit conducting between
signal (active) electrode and reference electrode [12]. Extra third electrode, called ground
electrode, is needed for getting differential voltage by subtracting the same voltages showing
at active and reference points. Minimal configuration for monochannel EEG measurement
consists of one active electrode, one (or two specially linked together) reference and one
ground electrode. The multi-channel configurations can comprise up to 128 or 256 active
electrodes.
Figure 9 : Different function of the brain
(S.Nairne, 2009)
As it is known from tomography different brain areas may be related to different
functions of the brain. Each scalp electrode is located near certain brain centres, e.g. F7 is
located near centres for rational activities, Fz near intentional and motivational centres, F8
close to sources of emotional impulses. Cortex around C3, C4, and CZ locations deals with
sensory and motor functions. Locations near P3, P4, and Pz contribute to activity of
perception and differentiation. Near T3 and T4 emotional processors are located, while at T5,
T6 certain memory functions stand. Primary visual areas can be found bellow points O1 and
O2. However the scalp electrodes may not reflect the particular areas of cortex, as the exact
location of the active sources is still open problem due to limitations caused by the non-
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homogeneous properties of the skull, different orientation of the cortex sources, coherences
between the sources, etc.
High impedance can lead to distortions which can be difficult to separate from actual
signal. It may allow inducing outside electric frequencies on the wires used or on the body.
Impedance monitors are built in some commercially available EEG devices. In order to
prevent signal distortions impedances at each electrode contact with the scalp should all be
below 5 K Ohms, and balanced within 1 K Ohm of each other. Similar standard is required
for clinical use of the EEG and for publication in most reputable journals. Practically,
impedance of the whole circuit comprising two electrodes is measured, but built in
impedance checks usually display results already divided by two. Control of all impedances
is desirable also after finishing every single measurement.
Several different recording reference electrode placements are mentioned in the
literature. Physical references can be chosen as vertex (CZ), linked-ears, linked-mastoids,
ipsilateral-ear, contralateral-ear, C7 reference, bipolar references, and tip of the nose.
Reference-free techniques are represented by common average reference, weighted average
reference, and source derivation. Each technique has its own set of advantages and
disadvantages. The choice of reference may produce topographic distortion if relatively
electrically neutral area is not employed. Linking reference electrodes from two earlobes or
mastoids reduces the likelihood of artificially inflating activity in one hemisphere.
Nevertheless, the use of this method may drift away "effective" reference from the midline
plane if the electrical resistance at each electrode differs [14]. CZ reference is advantageous
when it is located in the middle among active electrodes, however for close points it makes
poor resolution. Reference-free techniques do not suffer from problems associated with an
actual physical reference. Referencing to linked ears and vertex (CZ) are predominant.
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With modern instrumentation, the choice of a ground electrode plays no significant role
in the measurement [15]. Forehead (Fpz) or ear location is preferred [16], but sometimes
wrist or leg is also used. The combination of all active electrodes with reference and ground
electrode compose channels. The general configuration is called montage.
3.3.2 Advantages and Disadvantages of EEG
EEG has two clear advantages for brain research. The first is characteristic of any
electrical recording system high precision time measurements. Changes in the brains
electrical activity occur very quickly, and extremely high time resolution is required to
determine the precise moments at which these electrical events take place. To days EEG
technology can accurately detect brain activity at a resolution of a single millisecond (and
even less). Unlike other electrical recording devices that require inserting electrodes into the
brain, EEG electrodes are simply stuck onto the scalp. It is therefore a non-invasive
procedure that allows researchers clear access to a healthy human brain (which they would
not probe inside to explore, of course). In addition, EEG equipment is relatively inexpensive
compared with other devices and simple to operate.
The main disadvantage of EEG recording is poor spatial resolution. Since
measurements are taken at the scalp, the received signal is, essentially, the sum of the electric
field (in the direction perpendicular to the scalp) that is produced by a large population of
neurons. The spatial resolution of a single electrode is in the order of one centimetre of the
cortex, which contains hundreds of thousands of neurons. Particularly strong electrical
activity can be picked up by several neighbouring electrodes. The EEG signal, therefore, is
not useful for pinpointing the exact source of the activity, and it does not allow researchers to
distinguish between activities originating in different but closely adjacent locations. That
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said, today there are more advanced techniques available for analysing EEG which allow for
more accurate estimates of the signal source.
3.3.3 Overall of EEG
It is a sound of language for the brain nervous in electric way.
Table 3 : Summaries of advantages and disadvantages of EEG
Advantages Disadvantages
Painless
high precision time measurements
accurately detect brain activity
inexpensive
poor spatial resolution
have to take long time
4.0 CONCLUSION
From the research that we have conduct, we known that the most sensitive scan is the
PET/CT and this is followed by MRI and EEG were equally sensitive. MRI scans 3 times
more expensive than EEG .So, based on our opinion; we have concluded that MRI is better
than CT scan to scan the abnormalities. This is because MRI scan possible to take pictures
from almost every angle.
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5.0 REFERENCE
(Web Sites)
Cheour, M. (9 july, 2010). advantages of MRI . Retrieved 29 april, 2012, from livestrong.com:http://www.livestrong.com/article/170110-advantages-of-a-brain-mri/
Cherry, K. (2012). The Anatomy of the Brain . Retrieved 21 April, 2012, from About.comWeb site: http://psychology.about.com/od/biopsychology/ss/brainstructure.htm
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