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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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3

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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5

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.
http://www.webmd.com/hw-popup/magnetic-resonance-imaging-mrihttp://www.webmd.com/a-to-z-guides/magnetic-resonance-imaging-mrihttp://www.webmd.com/hw-popup/ct-or-cat-scanhttp://www.webmd.com/hw-popup/ct-or-cat-scanhttp://www.webmd.com/a-to-z-guides/magnetic-resonance-imaging-mrihttp://www.webmd.com/hw-popup/magnetic-resonance-imaging-mri


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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.
http://adam.about.com/encyclopedia/Isotope-study.htmhttp://adam.about.com/encyclopedia/Isotope-study.htm


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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


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


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

health, o. (2012). health and services cares . Retrieved 9 may, 2012, from OCHIOHEALTH:http://www.ohiohealth.com/pet-ctscanfaq

Hess, C. (5 August, 2008). knol . Retrieved 22 April, 2012, from knol Web site:knol.google.com/k/brain-ct-mri

Schwartz, A. (2008). Anopal Schwartz . Retrieved 20 April, 2012, from Anopal Schwartz:http://www.anapolschwartz.com/practices/gadolinium-nsf/blog/mri-side-effects.html

(Journal)

Cherry, K. (2012). The Anatomy of the Brain . Retrieved 21 April, 2012, from About.com

Web site: http://psychology.about.com/od/biopsychology/ss/brainstructure.htm

(Blog)

coconutwirelessss. (4 march, 2010). wordpress . Retrieved 29 april, 2012, from

coconutwireless: http://coconutwireless16.wordpress.com/

(Book)

Lahey, B. B. (2012). Psychology and Introduction Eleventh Edition, Mc Graw Hill

Coon, D., & Mitterer, J. O. (2008). Introduction to Psychology Twelfth Edition. CENGAGE

LEARNING.

S.Nairne, J. (2009). INTRODUCTION TO PYSCOLOGY. In J. S.Nairne, INTRODUCTION TO PYSCOLOGY (p. 547). Canada USA: Michele Sordi .

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