Karteikarten
EEG Basics
Karten in diesem Stapel (21)
- 1Alpha8-13 Hz
Occipital distribution
Attenuates with Eye opening
Alpha Squeak - 2Beta14-30 Hz
Frontal distribution
More prominent in drowsiness/light sleep - 3Theta4-8 Hz
diffuse distribution or bitemporal regions
increase in drowsiness - 4Delta>4 hz
Variable distribution
Normal in deep sleep, abnormal during wakefulness - 5Mu8-10 Hz
Central distribution
attenuates with contralateral extremity movement - 6What are the EEG characteristics are present in stage I sleep/drowsiness?slow rolling eye movements, V-waves, attenuation of alpha, central/frontocentral theta, enhanced beta, POSTS, hypnagogic hypersynchrony
- 7When are V waves first seen?as early as 2 months of age
- 8What EEG characteristics are present in stage II sleep?Sleep spindles, K complexes, V waves, attenuation of alpha, central/frontocentral theta, enhanced Beta, POSTS, Hypnagogic Hypersynchrony, Delta
- 9What EEG characteristics are present in stage III sleep?Mostly delta, with sleep spindles and K complexes
- 10What EEG characteristics are present in REM sleep?Low amplitude, mixed frequency, Rapid eye movements, saw tooth waves, EEG desynchronization
- 11What are the most prominent physiological artifacts which may be present on the EEG?EMG (muscle)
ECG
Sweat sway - 12What are the most prominent non-physiological artifacts which may be present on EEG?60 Hz/ alternating current
electrode artifact - 13Describe Bell's Phenomenonthe eye acts as a dipole with cornea as positive pole and retina negative pole. This causes artifact with eye movements- looking upwards or closing eyes causes a positive EEG deflection, and looking downwards/closing eyes causes a negative deflection
- 14What is Epilepsy?a disorder of the brain characterized by an enduring predisposition to
generate epileptic seizures and by the neurobiologic, cognitive, psychological, and social
consequences of this condition. - 15What are interictal Epileptiform discharges?Distinctive waves or complexes which are distinguished from the background and which resemble similar patterns that have been recorded in subjects with epilepsy
- 16What are the 4 morphologies of interictal discharges?Sharp waves, spikes, polyspikes, sharp and slow wave or spike and slow wave complex
- 17What are the four categories of electrographic response to photic stimulation?Visual evoked response, photic driving, Photomyogenic response, photoparoxysmal response
- 18What are the contraindications for hyperventilation?acute stroke, recent intracranial hemorrhage, large vessel stenosis, documented moya moya disease, cardiopulmonary disease, sickle cell disease
- 19What are normal responses to hyperventilation?no change OR symmetrical slow activity/ FIRDA / OIRDA
- 20Why is it important to ask time of last meal?Because hyperglycemia can cause a marked response to HV
- 21Which epilepsy syndromes commonly show activation with sleep?benign occipital epilepsy in infancy, Lennox-Gastaut syndrome, benign epileptiform central/midtemporal spikes, juvenile myoclonic epilepsy, frontal lobe epilepsy, Landau-Kleffner