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EEG

Link: posterior dominant rhythm

clinical significance

The presence of a normal reactive posterior dominant rhythm is indicative of a well-functioning brain and automatically rules out all sorts of pathology. In a patient with altered mental status where the differential includes seizures, encephalopathy, or something psychogenic, the presence of a normal reactive PDR is a very strong argument against the first two.

A wealth of EEG information can be found, in addition to the above at http://eegatlas-online.com/index.php/alphabetical-index/posterior-dominant-rhythm-guest.

This website is not a substitute for independent professional advice. Nothing contained in this site is intended to be used as medical advice. No articles, personal accounts, or other content are intended to be used to diagnose, treat, cure or prevent any disease, nor should it be used for therapeutic purposes or as a substitute for your own health professionals advice.

Link: Positions and brain function

Functional Analysis of MINI-Q II positions, and Use with Live Z-scores

A Window  to 4-channel EEG Assessment and Training 

Thomas F. Collura, Ph.D. 

This text describes the positioning of EEG electrodes and is a user-guide. It provides some interesting information on the regions associated with EEG tracing.

The full text can be found at http://www.brainm.com/help/Positions_and_brain_function.htm.

This website is not a substitute for independent professional advice. Nothing contained in this site is intended to be used as medical advice. No articles, personal accounts, or other content are intended to be used to diagnose, treat, cure or prevent any disease, nor should it be used for therapeutic purposes or as a substitute for your own health professionals advice.

Link: Does EEG pick up brain stem activity?

In breif: No.

This page briefly asks the  question if brain stem activity is picked up on EEG. Answered by Dr. Adam Smith. The full answer can be found at https://www.healthtap.com/user_questions/1036730-does-and-eeg-pick-up-brain-stem-neuron-activity.

Posted on 18th April, 2015 by T.A.O. to comments.

This website is not a substitute for independent professional advice. Nothing contained in this site is intended to be used as medical advice. No articles, personal accounts, or other content are intended to be used to diagnose, treat, cure or prevent any disease, nor should it be used for therapeutic purposes or as a substitute for your own health professionals advice.

Link: Introduction to EEG and MEG

The electrical activity of active nerve cells in the brain produces currents spreading through the head. These currents also reach the scalp surface, and resulting voltage differences on the scalp can be recorded as the electroencephalogram (EEG). The currents inside the head produce magnetic fields which can be measured above the scalp surface as the magnetoencephalogram (MEG). EEG and MEG reflect brain electrical activity with millisecond temporal resolution, and are the most direct correlate of on-line brain processing obtainable non-invasively. Unfortunately, the spatial resolution of these methods is limited for principal physical reasons. Even with an infinite amount of EEG and MEG recordings around the head, a non-ambiguous localisation of the activity inside the brain would not be possible. This “inverse problem” is comparable to reconstructing an object from its shadow: only some features (the shape) are uniquely determined, others have to be deduced on the ground of additional information. However, by imposing reasonable modelling constraints or by focussing on rough features of the activity distribution, useful inferences about the activity of interest can be made.

The full text can be found at http://imaging.mrc-cbu.cam.ac.uk/meg/IntroEEGMEG.

This website is not a substitute for independent professional advice. Nothing contained in this site is intended to be used as medical advice. No articles, personal accounts, or other content are intended to be used to diagnose, treat, cure or prevent any disease, nor should it be used for therapeutic purposes or as a substitute for your own health professionals advice.

Link: EEG in the diagnosis, classification, and management of patients with epilepsy

The human electroencephalogram (EEG) was discovered by the German psychiatrist, Hans Berger, in 1929. Its potential applications in epilepsy rapidly became clear, when Gibbs and colleagues in Boston demonstrated 3 per second spike wave discharge in what was then termed petit mal epilepsy. EEG continues to play a central role in diagnosis and management of patients with seizure disorders—in conjunction with the now remarkable variety of other diagnostic techniques developed over the last 30 or so years—because it is a convenient and relatively inexpensive way to demonstrate the physiological manifestations of abnormal cortical excitability that underlie epilepsy.

 

The full text can be found at http://jnnp.bmj.com/content/76/suppl_2/ii2.full.

 

 

 

 

This website is not a substitute for independent professional advice. Nothing contained in this site is intended to be used as medical advice. No articles, personal accounts, or other content are intended to be used to diagnose, treat, cure or prevent any disease, nor should it be used for therapeutic purposes or as a substitute for your own health professionals advice.

Video: EEG (Electroencephalogram) & EMU (Epilepsy Monitoring Unit) – About your Mayo Clinic Test

This website is not a substitute for independent professional advice. Nothing contained in this site is intended to be used as medical advice. No articles, personal accounts, or other content are intended to be used to diagnose, treat, cure or prevent any disease, nor should it be used for therapeutic purposes or as a substitute for your own health professionals advice.

Link: Autoimmune encephalitis: a case series and comprehensive review of the literature

Encephalitic syndromes are a common medical emergency. The importance of early diagnosis and appropriate treatment is paramount. If initial investigations for infectious agents prove negative, other diagnoses must be considered promptly. Autoimmune encephalitides are being increasingly recognized as important (and potentially reversible) non-infectious causes of an encephalitic syndrome. We describe four patients with autoimmune encephalitis—3 auto-antibody positive, 1 auto-antibody negative—treated during the last 18 months. A comprehensive review of the literature in this expanding area will be of interest to the infectious diseases, general medical and neurology community.

 

http://qjmed.oxfordjournals.org/content/104/11/921.long

Copyright © 2011 Association of Physicians of Great Britain and Ireland | Authors T. Wingfield , C. Mchugh , A. Vas , A. Richardson , E. Wilkins , A. Bonington , A. Varma

This website is not a substitute for independent professional advice. Nothing contained in this site is intended to be used as medical advice. No articles, personal accounts, or other content are intended to be used to diagnose, treat, cure or prevent any disease, nor should it be used for therapeutic purposes or as a substitute for your own health professionals advice.

Video: Inside Out Epilepsy

This website is not a substitute for independent professional advice. Nothing contained in this site is intended to be used as medical advice. No articles, personal accounts, or other content are intended to be used to diagnose, treat, cure or prevent any disease, nor should it be used for therapeutic purposes or as a substitute for your own health professionals advice.

Video: EEG Stage 2 Sleep

This website is not a substitute for independent professional advice. Nothing contained in this site is intended to be used as medical advice. No articles, personal accounts, or other content are intended to be used to diagnose, treat, cure or prevent any disease, nor should it be used for therapeutic purposes or as a substitute for your own health professionals advice.

Link: Frontal predominance of a relative increase in sleep delta and theta EEG activity after sleep loss in humans (PDF)

The effect of sleep deprivation (40 h) on topographic and temporal aspects of electroencephalographic (EEG) activity during sleep was investigated by all night spectral analysis in six young volunteers. The sleep-deprivation-induced increase of EEG power density in the delta and theta frequencies (1-7 Hz) during nonREM sleep, assessed along the antero-posterior axis (midline: Fz, Cz, Pz, Oz), was significantly larger in the more frontal derivations (Fz, Cz) than in the more parietal derivations (Pz, Oz). This frequency-specific frontal predominance was already present in the first 30 min of recovery sleep, and dissipated in the course of the 8-h sleep episode. The data demonstrate that the enhancement of slow wave EEG activity during sleep following extended wakefulness is most pronounced in frontal cortical areas.

 

The fulll document can be downloaded via PDF at this link – http://www.researchgate.net/profile/Christian_Cajochen/publication/11955869_Frontal_predominance_of_a_relative_increase_in_sleep_delta_and_theta_EEG_activity_after_sleep_loss_in_humans/links/02bfe5113b73dd3097000000.pdf.

Copyright © Authors Cajochen, C., Foy, R., Dijk, D. J., Czeisler, C. A.

This website is not a substitute for independent professional advice. Nothing contained in this site is intended to be used as medical advice. No articles, personal accounts, or other content are intended to be used to diagnose, treat, cure or prevent any disease, nor should it be used for therapeutic purposes or as a substitute for your own health professionals advice.