Electroencephalogram Test on Alcoholics and Non Alcoholics

Electroencephalogram Test on Alcoholics and Non AlcoholicsINTRODUCTIONThe electroencephalogram ( electroencephalogram) is a posting manpowert of the electric screening in the long-sufferings witticism. This galvanizing drill is produced by the firing of neurons (a nerve cell) within the drawing and varies from patient to patient. In 1875, English physician Ric touchy Caton discoered the presence of electrical performance in the spirit however, it was non until German neurologist Han Berger in 1924 employ his ordinary radio set equipment to amplify the wizpowers electrical bodily process so he could record it on paper. He noticed that beatic changes in brain dithers varied with the individuals landed estate of consciousness ( ease, anesthesia, epilepsy) and that respective(a) regions of the brain do not emit the similar brain wave frequency simultaneously. (http//www.bio- medical exam.com). The encephalogram was given its name by Berger who use the German te rm elektrenkephalogramm to describe the intenseal representation of the electrical currents generated in the brain. The scientific comm unit of bary of Bergers time did not believe the conclusions he made and it took anformer(a) five years until his conclusions could be verified by center of experimentation by Edgar Douglas Adrian and B.C.H Matthews. These experiments made head-waves and other scientists began studying the field and in 1936 W. Gray Walter demonstrated that this technology could be employ to pin orchestrate a brain tumor. He used a large progeny of teeny electrodes that he pasted to the scalp and found that brain tumors caused aras of atypical electrical activity. (Romanowski 1999) and http//www.ebme.co.uk.The brain is the central part of the nervous placement, which is the most complicated system in the body. It is an intriguing organ that has been studied magnateful from the time of brain bring ab protrudement in the fetus. The military man brain wei ghs about 1.5kg in swelleds. The cerebrum, which forms the mint of the brain, is divided into both noetic hemispheres, the right hemisphere and the left hemisphere. Each hemisphere of the brain interacts with nonp aril half of the body, nevertheless(prenominal) for unknown reasons, it is the right align that conquers the left half of the body and the left half of the brain that controls the right half of the body. However, in most pack, the left hemisphere of the brain is tough in langu progress and creativeness, period the right side of the brain is more than involved in understanding and judgment. The cerebrum, which is located in the forebrain, is the largest part of the human brain and is associated with higher brain functions much(prenominal) as thought and action. The cerebral cortex is divided into four sections c on the wholeed lobes. These determine the searchal lobe, parietal lobe, occipital lobe and temporal lobe. The frontal lobe is associated with reaso ning, planning, parts of speech, movement and problem solving. The parietal lobe is associated with movement, orientation, realization and perception of stimuli. The occipital lobe is associated with optical processing and the temporal lobe is associated with perception and reference of auditory stimuli, memory and speech. (Khan 2009).Over the years with advancements in technology electroencephalogram electrodes, amplifiers and output devices were improved and scientists learned the best places to put the electrodes and how to diagnose its conditions. They oerly disc overed how to create electrical maps to produce an image of the brains jump and straight off pneumoencephalogram machines call for multiple channel, computer storage memories and specialized packet that fundament create an electrical map of the brain. (Romanowski 1999). encephalogram has come a long way since its inception more than 100 years ag unmatchable and it is used primarily in studying the properties of cerebral and neural networks in neurosciences (Michel et al. 2004). It is used to supervise the neurodevelopment and slumber patterns of infants in the intensive c ar unit and ultimately enable physicians to use the training to improve daily medical dish out (Scher 2004). The emergence of neurofeedback or electroencephalogram biofeedback has expanded the application of pneumoencephalogram for both cases with particular dis sends or among healthy participants. encephalogram frequencies in neurofeedback discharge be controlled to influence authoritative cognitive performance and memory task, (Vernon et al. 2003). interactive Brainwave Visual Analyzer (IBVA) is a form of biofeedback for the brain (neurofeedback). Its a training process of using technology to provide you with more information about what your body is doing than your ordinary senses provide. This feedback helps you learn to use your mind to develop greater control over your body, or, in the case of neurofeedba ck, your brain. IBVA detects brainwaves phasing at urge ons metric in units of Hz for cycles per foster between 0 and 60 Hz. It is used for pile state and hypnosis depth psychology, image programming for sports training, super learning (photo reading) and for study. pneumoencephalogram biofeedback is effective in treating psychological disorders such(prenominal) as trouble deficit, depression, inveterate anxiety disorder, chronic alcoholics and neurological disorders bid epilepsy. Patients with epilepsy that bathnot be controlled by medicament will often confuse surgery in order to get the damaged tissue. The encephalogram plays an important role in localizing this tissue. Special electrodes preempt be inserted through the cortex or alternatively a power grid of electrodes displace directly on the surface of the cortex. These recordings, often called Long stipulation Monitoring for Epilepsy (LTME), groundwork be carried out for periods ranging from 24 hours to 1 week . The pneumoencephalogram save will repoint which beas of the brain should be functionally removed. (Smith n.d). another(prenominal) important application of the electroencephalogram is used by anesthesiologist to monitor the depth of anesthesia. EEG measures interpreted during anesthesia exhibit stereotypic changes as anesthetic depth increases. These changes include complex patterns of loss of consciousness clears (loss of responses to literal commands and/or loss of righting reflex). As anesthetic depth increases from light surgical levels to deep anesthesia, the EEG exhibits disrupted rhythmic waveforms, high amplitude ignite suppression activity, and finally, very base amplitude isoelectric or flat limit activity.Quantitative EEG (QEEG) has come a long way in its relatively dead behavior in terms of use in clinical practice. Now, as clinicians become aware of the scientific soil and power of using parametrically based measures of QEEG to assess an individual again st age-matched populations, they pass new ways to employ this technique. There are literally thousands of univariate electrophysiological measures that can be derived, modify and normed into Z-scores (standard scores), to be used to indicate degrees of derivations from normal. QEEG offers a powerful application cats-paw as a method for providing convergent evidence in the appellation of clinical syndromes for individuals. Over the years, various clinicians using QEEG suck attempted to generate brain maps to correspond with specific disorders such as learning disorders, attention deficit hyperactivity disorders (ADHD), chronic alcoholism and depression. bandage certain features whitethorn be associated with general types of impairments, the utilization of univariate sets of features have, to date, been unable to provide defining specific psychiatric disorders. Looking at only(prenominal) the univariate features without recognizing the full space of all deviate measures, wh izz and only(a) whitethorn not realize the particular cluster of measure that may contri juste to specific disorders with distinct features. Multivariate statistical measurement sets encompass the space of regions by measurement, riposteing distinctive complex patterns which yield greater sensitivity in discriminability. (Budzynski, Evans and Abarbanel 2008).The basic systems of an EEG machine include data collection, storage and let out. The components of these systems include electrodes, connecting wires, a computer control faculty and a video showing device. The electrodes used can be either surface or needle electrodes. Needle electrodes provide greater signal pellucidness because they are injected directly into the body and this in turn eliminates signal muffling caused by the skin. Surface electrodes on the other hand are disposable models such as the tab, ring and bar electrodes as well as recyclable disc and finger electrodes. These electrodes may too be combined in to an electrode crest that is placed directly on the head (Romanowski 2002).EEG amplifiers convert bl each(prenominal)ed signals from the brain into a more discernable signal for the output device. An amplifier may be set up as follows a pair of electrodes detects the electrical signal from the body, wires connected to the electrodes transfer the signal to the showtime section of the amplifier (buffer amplifier). here the signal is electronically stabilized and amplified by a factor of 5 10 and then next in line is a prototypal derivative pre-amplifier that filters and amplifies the signal by a factor of 10 100. After limiting through these amplifiers the signals are multiplied by hundreds or thousands of times. Multiple electrodes are used since the brain produces unalike signals at different points on the skull and the number of channels that an EEG machine has is related to the number of electrodes used. The amplifier is able to yield the different in flood tide signa ls and cancel out ones that are identical this sloppeds that the output from the machine is actually the difference in electrical activity picked up by the two electrodes. This therefore means that the placement for each electrode is critical because the closer they are to each other the less differences in brainwaves will be save (Romanowski 2002).EEG SYSTEM LAYOUT (www.medicalengineer.com)Recording of the electrical activity in the brain takes place over a short period of time from where information is binded from electrodes stationed at specific points on the patients head. Electrodes are placed on the scalp of the head commonly after preparing the scalp area by light abrasion to reduce impedance out-of-pocket to dead skin cells. In order for the placement of these electrodes to be ordered throughout an inter topicly recognized method called the 10-20 System is followed. The 10 and the 20 gives the actual distances between adjacent electrodes. This distance can either be 10% or 20% of the total front-back or right-left distance of the skull, i.e. the nasion inion and preauricular points respectively, http//www.neurocarelaunches.com. special(prenominal) measurements from bony landmarks (inion, nasion and preauricular point) are used to generate a system of lines, which outflow crossways the head and intersect at intervals of 10% or 20% of their total continuance as mentioned above. The standard set of electrodes consists of 21 recording electrodes and one ground electrode. The distance between the nasion and inion is measured along the midplane and the frontopolar point, Fpz, is tag at 10% above the nasion. Frontal (Fz), central (Cz), parietal (Pz) and occipital (Oz) points are marked at intervals of 20% of the entire distance, exit 10% for the interval between Oz and inion (see Diagram 1). The midline points Fpz and Oz routinely do not receive any electrode. The distance between two preauricular points across Cz is measured. Along this line, the transverse position for the central points C3 and C4 and the temporal points T3 and T4 are marked 20% and 40% respectively from the midline (see Diagram 2). The circumference of the head is measured form the occipital point (Oz) through temporal points T3 and T4 and the frontopolar point (Fpz). The longitudinal measurement for Fp1 is located on that circumference, 5% of the total length of the circumference to the left of Fpz. The longitudinal measurements for F7, T3, T5, O1, O2, T6, T4, F8 and Fp2 are at the distance of 10% of the circumference (see Diagram 3). An electrode is then placed on each of the two ear lobes. (Jasper 1958) and (Jasper 1983).In order for the EEG test to be a success and the best possible results obtained the preparation the patient must endure is very basic since only a good night residual before the test is needed along with a grease-free head on the morning of the test. However, it can get more technical should the patient be taking any medication and information on this medication must be passed on to the doctor. An EEG test may be through in a hospital or in a doctors subprogram by an EEG technologist. Using the internationally recognized 10-20 system, the electrodes are placed on the patients head and the technologist can then put the patient through a manikin of different tasks such as gain/subtraction of numbers, breathing deeply and apace or he can ask the person to wear a goggles sending out a strobe (bright flashing light). These tasks take place normally at 15-20 second durations with 30 second breaks in between. The electrodes attached to the patients head are connected by wires to a computer which records the electrical activity in the brain. An EEG test can last between 1-2 hours and the results obtained from it can be read by a certified doctor known as a Neurologist.The results of an EEG test are in the form of waveforms which gives snappy information about the patient. Waves can either be alpha waves (frequenc y of 8 to 12 cycles per second), Beta waves (frequency of 14 to 50 cycles per second), Delta waves (frequency less than 5 cycles per second) or Theta waves (frequency of 4 to 7 cycles per second). Basic alpha waves, which originate in the cortex, can be recorded if the patient closes his eyes and put his brain at rest as much as possible. Beta activity is a normal activity present when the eyes are open or closed. It tends to be seen in the channels recorded from the centre or front of the head. Some do drugss however, tend to increase the amount of beta activity in the EEG. Theta activity can be classified as both a normal and affected activity depending on the age and state of the patient. In adults it is normal if the patient is drowsy. However, it can also indicate brain disfunction if it is seen in a patient who is alert and awake. In new(a)er patients, theta activity may be the main activity seen in channels recorded from the back and central areas of the head. Delta activity is only normal in an adult patient if they are in a moderate to deep sleep. If it is seen at any other time it would indicate brain dysfunction. freakish activity may be seen in all or close to channels depending on the underlying brain problem. The stroke or blow on the head. (Niedermeyer, Ernest and Lopes da Silva 2004).ALPHA thriveSBETA WAVESTHETA WAVESDELTA WAVES (http//www.electropsychology.com)Each type of wave mentioned above gives us information about the patient, for example in a normal patient we tend to observe mainly alpha or beta waves since both sides of the brain give tongue to similar patterns of electrical activity. A normal person in this case is described as one who doesnt possess any of the following maladys or injuries head injury, neurological unhealthiness, convulsions, drug abuse, alcohol abuse, memory difficulties, confusion, depression, delusions/hallucinations and learning disabilities. If the patient is abnormal you may find two sides of the brain giving different electrical activities and this may mean there is a problem in one side of the brain caused by a brain tumor, stroke, infection or epilepsy.EPILEPTIC SPIKES AND WAVE DISCHARGES MONITORED WITH EEG (http//www.webmd.com).A stroke, which is a sudden disruption in simple eye flow to brain, caused by blockage or bleeding of a ocellus vessel and Epilepsy which is a nervous system disorder, can cause abnormal electrical activity in the brain and this abnormality can be seen from the results of an EEG test. Another common disease which is on the escalation presently is Alcoholism. This disease is known as alcohol dependence syndrome i.e. the most severe correspond of a group of drinking problems, and the person who has this disease is known as an alcoholic. Alcohol clearly affects the brain since impairments such as difficulty in walking, blurred vision, slurred speech, slowed reaction times and impaired memory are detectable after only one or two drinks and is right away resolved when drinking stops. We do know that heavy drinking may have extensive and far-reaching effects on the brain ranging from simple slips in memory to permanent and debilitating conditions that require looktime custodial care (White 2003). According to the number 1 website for alcoholism, http//www.alcoholism.about.com, studies have shown that brains of alcoholics are little, lighter and sh do workken when compared to that of a normal person. The cerebral cortex or gray weigh in the brain controls all the complex mental activities and this is filled with neurons connected by single long fibers which make up the hard fit out of the brain. Heavy consumption of alcohol is particularly damaging on this hard wiring hence the reason why the brain becomes lighter and smaller and the alcoholic severe impairments.SCHEMATIC DRAWING OF THE HUMAN BRAIN, SHOWING REGIONS defenceless TO ALCOHOLISM-RELATED ABNORMALITIES. (http//www.elvizy.com).Another major organ apart from the brain w hich alcohol affects is the colorful. long abusers of alcohol usually have some degree of colored damage, ranging in severity from asymptomatic and reversible fatty liver, through hepatitis and cirrhosis of the liver of the liver, to primary liver cell carcinoma, which is usually fatal. Evidence is accruing to suggest that this spectrum of disorders may be a progressive series of stages of increasing severity. Alcohol liver damage accounts for the coarse majority of cases of cirrhosis in patients coming to autopsy. Further, mortality rate from cirrhosis is associated with national per capita levels of consumption. In North-American studies, alcoholic cirrhosis was one of the top five causes of mortality for pack aged 25 to 64 years in the sixties and 1970s. In 1992, Savolainen, Penttila and Karhunen investigated the relationship between alcohol intake and liver cirrhosis in Finland, where the per capita consumption rates doubles between 1969 and 1974. Rates of liver cirrhos is mortality rose from 4.2 to 9.7 per 100,000 between 1968 and 1988. The mortality rate from cirrhosis has been estimated as between seven and thirteen times higher in alcoholics than in those who do not drink. Although it is more common in men than in women, there is evidence that liver disease progresses more rapidly in the female person alcohol abuser (Knight and Longmore 1996). Alcoholics, they say, are not like helpless victims of measles or cancer. They may have impaired control but they can gain control through will-power and learning certain techniques. While the cause of alcoholism is unknown, a number of risk factors have been identified. These include availability (Australian Aborigines illustrate the importance of availability of alcohol as a risk factor since when they were forbidden to drink there ostensibly was a low rate of alcohol abuse), family history (alcoholism in the family is believably the strongest predictor of alcoholism occurring in particular individual s), sex (studies have affirm higher incidence of alcoholism in men than in women), age (alcoholism in men usually develops in the teens, twenties and thirties while in women it often develops later), geography (people living in urban or suburban areas are more often alcoholics than those living in farms or in small towns), occupation (waiters, bartenders, Dockers, musicians, authors and reporters have relatively high cirrhosis rates whereas accountants, postmen and carpenters have relatively low rates), religion (almost all Jews and Episcopalians drink, but alcoholism among Jews is uncommon and appear relatively low among Episcopalians, whereas Irish Catholics in the USA and UK have high rates of alcoholism) and school difficulty ( vicarious school dropouts have a record of existence irritable and affliction and experience feelings of guilt and remorse which drives them to become alcoholics. These lose interest in life and contemplate suicide which is a common outcome of alcohol ism). quite a little who have been drinking large amounts of alcohol for long periods of time run the risk of developing serious and persistent changes in the brain. Damage may be as a result of the alcohol on the brain or may result indirectly, from a poor health situation or from severe liver disease (Goodwin 2000).Alcoholics are not all alike since they experience different degrees of impairment and the disease has different origins for different people. Consequently, interrogationers have not found conclusive evidence that any one variable is solely responsible for the brain deficits found in alcoholics. Characterizing what makes some alcoholics vulnerable to brain damage whereas others are not remains the prevail over of active research. The good news is that most alcoholics with cognitive impairment show at least some improvement in brain mental synthesis and functioning within a year of abstinence, though some people take much longer (Bates, Bowden and Barry 2002), (Gans ler 2000) and (Sullivan 2000). Clinicians must consider a variety of treatment methods to help people stop drinking and to recover from alcohol related brain impairments, and tailor these treatments to the individual patient. Development of these therapies would occur over time with advancements in technology. Brain imaging techniques are used by medical doctors so that they can monitor the course of these therapies and see how booming they are. This monitoring is important since imaging can reveal information such as structural, functional and biochemical changes in the living patient over a period of time. Promising new medications also are in the early stages of development, as researchers strive to design therapies that can help clog alcohols harmful effects and promote the growth of new brain cells to take the place of those that have been damaged by alcohol.OBJECTIVESElectroencephalogram or EEG is a tool used to image the brain while it is performing a cognitive task. This a llows us to detect the location and magnitude of brain activity involved in the various types of cognitive functions we study. EEG allows us to view and record the changes in your brain activity during the time you are performing the task. Results from an EEG is extremely useful since Neurologists use this to diagnose ictus disorders (epilepsy), brain tumors, brain hemorrhage, cerebral infarct, head injury, sleep disorders and in convinced(p) death in someone who is in a coma. (Tatum 2007).In this research intention we have narrowed the study of the EEG to examine male alcoholic and non-alcoholic patients. The general object lens of this project requires us to compare EEG results obtained from testing alcoholic and non-alcoholic patients at the Eric Williams Medical Sciences Complex. An alcoholic is one who suffers from the disease known as alcoholism and cannot control how much they consume. Identification of one involves an objective assessment regarding the damage that imbibi ng alcohol does to the drinkers life compared with the indwelling benefits the drinker perceives from consuming alcohol. While there are many cases where an alcoholics life has been significantly and obviously damaged, there are always borderline cases that can be difficult to classify. Apart from the general objective of this research project there were many smaller tasks which had to be completed in order for us to obtain successful results and hence fulfill our main objective.The first task of this research project entailed sourcing alcoholic and non-alcoholic volunteers to test. This was particularly important since the successfulness of this task would revolve solely around our general objective. However, once this first task was sorted out and patients were tested, from the results obtained we used analytical methods such as monopolar absolute power maps, coherence maps and chaos analysis to help us get a clearer illustration of the results and hence make the general objectiv e much clearer.The second objective of this project required us to have sufficient background information on the EEG, the experimental methodology when conducting an EEG (10-20 System), analytical methods used to illustrate EEG results, alcoholism, EEG on alcoholics and other general topics revolving around the area of research. In order for this to be a success the necessary books, journals, websites had to be extractiond and read before any hard-nosed work commenced.Once these two tasks were performed successfully, we then set out to obtain our general objective of analyzing and comparing EEG results of both alcoholics and non-alcoholics.LITERATURE retreadAn electroencephalogram (EEG) is a test that measures and records the electrical activity of your brain by using surface biopotential electrodes. These electrodes are attached to the patients head and hooked by wires to a computer which records the brains electrical activity on the screen or on paper as wavy lines (waveforms). A mong the basic waveforms are the alpha, beta, theta and delta rhythms. Alpha waves occur at a frequency of 8 to 12 cycles per second in a regular rhythm and are present only when you are awake but have your eyes closed. They normally go away when you open your eyes or start concentrating mentally. Beta waves occur at a frequency of 13 to 30 cycles per second and are usually associated with the use of sedative medications. Theta waves occur at a frequency of 4 to 7 cycles per second and are most common in children and young adults. Delta waves occur at a frequency of 0.5 to 3.5 cycles per second and generally occur in young children or during deep sleep. During an EEG, typically about 20-30 minutes of activity are evaluated and special attention is paid to the basic waveforms, but brief bursts of energy and responses to stimuli, such as light are also examined, (The university of Texas medical branch, http//www.utmbhealthcare.org).Results from an EEG test can tell a dole out about the patient and is a read by a neurologist. The waves recorded can be classified as normal or abnormal. Abnormal waves can indicate medical problems, whereas different types of normal waves can indicate various states or activity levels. The value of understanding the normal EEG lies in developing the foundation to provide a clinical basis for identifying abnormality. Knowledge of normal waveform variations, variants of normal EEG that are of ambiguous importee, and fluctuations of normal EEG throughout the lifecycle from youth to the aged are inherent to provide an accurate impression for clinical interpretation. When abnormality is in doubt, a conservation impression of normal is proper. EEG produces a graphic display of a difference in voltages from two sites of brain functions recorded over time. Extra cranial EEG provides a broad survey of the electrocerebral activity throughout both hemispheres of the brain while intracranial EEG provides center EEG recording directly fro m the brain through surgically ingrained electrodes that are targeted at specific regions of the brain. (Tatum 2007). Information about a delicate or focal cerebral dysfunction, the presence of interictal epileptiform discharges (IEDs), or patterns of special significance may be revealed from an abnormal EEG. For the successful interpretation of an abnormal EEG, one must first understand the criteria necessary to define normal patterns. While a normal EEG does not exclude a clinical diagnosis (i.e. epilepsy), an abnormal finding on an EEG may be supportive of a diagnosis (i.e. in epilepsy), be indicative of cerebral dysfunction (i.e. focal or generalized slowing), or have nada to do with the reason that the study was performed (i.e. in headache). It is in the clinical application of the EEG findings that imparts the utility of EEG. (Tatum 2007). Two important applications involving EEG wave salmagundi are diagnosis of sleep disorders and construction of brain-computer interfaces to assist disabled people with daily living tasks.Sleep occupies roughly one-third of a persons life and is indispensable for health and well-being. Sleep apnea is a disorder characterized by a ten-second or longer pauses in breathing during sleep. A person with sleep apnea cannot self-diagnose the presence of this disorder so in order to make diagnoses for sleep disorders, physicians usually need to study patients sleep patterns through sleep recording. A typical sleep recording has multiple channels of EEG waves coming from the electrodes placed on the subjects head. The waves from a healthy subject are unchanging about zero and show relatively high variability and low correlation whilst the waves from a person with sleep difficulty show less variability and higher correlation. Measuring EEG signals is a non-intrusive procedure since it does not cause any pain to the subject. Sleep staging is the pattern fruition task of classifying sleep recordings into sleep stages continuous ly over time and is performed by a sleep stager. These sleep stages include rapid-eye movement (REM) sleep, four levels of non-REM sleep and being awake. Sleep staging is crucial for the diagnosis and treatment of various sleep disorders. In order to make many EEG-based applications practical abundant for routine use, it is necessary to achieve high accuracy in EEG wave salmagundi. For physicians specializing in sleep disorders, improving sleep stage classification accuracy can increase both their diagnostic accuracy and the speed with which they make diagnosis. (Min and Luo. n.d).plat SHOWING EEG SLEEP PATTERNS, (http//www.benbest.com)Brain-Computer interfaces (BCIs) are soon being developed to facilitate the control of computers by people who are disabled. As disabled people think about what they want to have the computer do, their thinking is classified based on their EEG waves andcorresponding instructions are automatically executed by the computer. Accurate EEG wave classifi cation is a critical requirement for computers to receive straighten out instructions. There are various kinds of BCIs with the most promising one being the P300 BCI using EEG signals. This is so because of its non-invasiveness, ease of use, portability and low set-up cost. In neuroscience, P300 refers to a neutrally-evoked potential component of EEG. (Min and Luo. n.d). Quantitative EEG signal analysis involves the shimmy of the EEG signal into numerical values that can be used to examine selected EEG features. Once a specific feature of the EEG has been quantified, it can be displayed using various graphical methods such as topographic mapping or spectral trend monitoring. Other applications of three-figure analysis include automated event staining, intraoperative or ICU monitoring, and source localization. Normative databases of quantitative EEG features (such as the peak alpha rhythm frequency or amount of alpha reactivity) can be used for statistical comparisons in research studies. Statistical quantitative EEG analysis is not yet considered reliable as an independent measure of abnormal brain function for clinical purposes. Topographic mapping refers to the graphical display of the distribution of a particular EEG feature over the scalp or cortical surface. Advanced forms of topographic mapping attempt to display EEG activity as it might be seen at the cortical surface by superimposing a color or gray eggshell image of the EEG feature onto the cortical surface image taken from the subjects MRI. More simplified forms of topographic mapping create a graphic display of an EEG feature over an imaginary head surface. any methods of topographic mapping depend heavily on montage construction. (Fisch and Spehlmann 1999).DIAGRAM SHOWING AN EEG TOPOGRAPHIC MAP, (http//www.cerebromente.org)Automated event detection is a form of quantitative analysis in which certain signal characteristics are used to classify an EEG change. It is most commonly applied to the detection of electrographic seizures during epilepsy monitoring. Intraoperative EEG monitoring is performed using continuous routine EEG visual inspection alone or in combination with quantitative EEG monitoring. The most common application of intraoperative EEG monitoring is for ca