STUDY GUIDE: Follow along with Larry Head as he walks you through the basics of EEG. This workbook is designed to follow the online video series.
FOUNDATIONS IN EEG VIDEO SERIES: Join Larry online as he introduces you to basic EEG concepts and provides you with the knowledge necessary to perform an EEG study. It does not matter if you are a beginner, cross-training allied health professional, or practicing technologist in this video series you will learn valuable information, tips and tricks to improve your EEG knowledge and practices. This course is also great for those preparing for their boards.
Topics covered include:
- Measuring and Marking,
- Localization and Polarity,
- EEG Pattern Recognition,
- Artifacts, and
- Activation Procedures
During this part of the course, Larry will discuss the basics of head measurement and electrode application. He will introduce you to head landmarks and techniques that make it possible to properly measure a patient’s head. Additionally, he will introduce you to the 10-20 System of Electrode Placement nomenclature, electrode planes, and proper marking technique. Finally, this section finishes with a detailed demonstration of measuring and marking.
A skilled technologist understands how to use the EEG instrument. This presentation will teach you how to properly calibrate the machine and how to use the jackbox to attach the patient, via electrodes, to the EEG instrument.
Next Larry will give a detailed explanation of the differential amplifier. A thorough understanding of the differential amplifier is helpful in understanding montages, localization and polarity, and signal amplitude.
Larry will next guide you through a detailed explanation of the relationship between the voltage of a signal, the amplitude of that signal and the sensitivity setting of the machine. You will learn the formulas to calculate voltage, sensitivity, and amplitude by using the Sensitivity Pie. Larry will also pose various scenarios to practice calculating each of these.
One of the most difficult concepts for technologists to learn is the how filters function. Larry will teach you the types of filters, how to use each and the effect filter changes have on EEG signals. Additionally, he will discuss time constants and their relationship to the low filter.
Next, he will revisit the reference electrode and how electrical signals are brought into the machine from the patient and how they can be displayed. He will explain paper speed, and when and why it should be changed.
Finally, the Instrumentation presentation concludes with a discussion of grounding and the ground electrode.
Looking at a person from the front, side, and back gives you three different views of the same person. Using different montages does the same on an EEG, it provides differing ways of looking at the electrical energy of the brain. In this presentation you will learn the types of montages and the variations of each type. Larry will teach you how to design and read montages.
A review of the differential amplifier and montages will lay the foundation for mastering localization techniques. You will learn the difference between generalized, lateralized, and localized brain activity. You will develop skill in determining how to recognize a focal discharge. You will learn localization techniques specific to montage type and how to use the Polarity Square to determine the polarity of an event. These skills will help you as you master pattern recognition.
Larry leads in an explanation of EEG terminology used to describe EEG signals. Each term will be defined and an example presented for the student to gain a solid foundation to record and analyze EEG. Terms include frequency, duration, voltage, sensitivity, morphology, location, phase, polarity, symmetry and synchrony, periodicity, reactivity, and variability. In this portion of the presentation you will understand the meaning of each term and see how it relates to the EEG.
In order to perform a technically adequate EEG the technologist must be able to identify the waveforms and patterns of the normal, normal variant, or abnormal EEG. Larry will guide you through the steps of pattern recognition. You will develop skill in applying the terms previously learned to identify the characteristics of each pattern.
You will apply your pattern recognition skills to identify some of the more common EEG abnormalities. A description of the EEG characteristics, examples of the pattern, and the symptoms associated with each pattern are discussed in detail. Some of the patterns you will learn to identify include background changes, delta, PLEDS, alpha coma, triphasic waves, burst suppression, periodic patterns, and electrocerebral inactivity.
Electrical signals can show up on the EEG that are not generated by the brain; artifacts. As a technologist you must be able to differentiate artifact from cerebral signals. Larry will help you develop the knowledge and skill necessary to identify artifacts and how to eliminate or monitor them.
During an EEG a patient may be asked to hyperventilate and may be exposed to blinking lights. As a technologist you will learn how to perform each activation procedure, the contraindications to performing each, possible artifacts that may be seen, and the normal and abnormal responses of each.