G is for generalized Activity that affects the brain as a whole, or is present in every channel of the EEG. Also can use the word diffuse.

7 y/o male being evaluated for episodes of starring off, occurring multiple times daily

H is for hyperventilation Activation procedure consisting of deep regular breaths of about 18-24 bpm. This causes constriction of cerebral arteriolar system and hypoxia (low levels of oxygen in the blood). Should be performed for 2-3 minutes May cause normal high amplitude, generalized slowing pattern known as a “build-up response”. Performed to illicit 3Hz generalized spike and wave discharges in patients with petit mal or absence seizures. Contraindications include: cardiovascular problems, respiratory disorders, extreme hypertenison, subarachnoid hemorrhage, or recent stroke.

6 y/o female being evaluated for behavioral problems…eeg to rule out seizures. Pt is currently on no medications

H is also for history Document age, family history , pt symptoms, relevant medical history, behavior state of patient, last episode occurrence, medications, or auras. Date and time of recording should also be annotated. As well as record ID.

I represents “Intermittent” Term that means: happens sporadically. It is activity that may come and go.

K is for K-complex. High amplitude delta wave activity that occur diffusely, but predominately over the vertex region. The slow, delta wave activity may be followed by a short period of 8-12 cps alpha-like activity. Most prominate in stage II sleep. Some sources say the are products of slight arousal. Best seen in a transverse montage.

L is for localization The act of isolating the origin of the abnormality. In a referential montage, localize by highest amplitude. In a bipolar montage, localize by phase reversal.

M is for montages.. System of grouping electrode pairs in a specific order. A referential montage consists of groupings of one active (scalp) electrode, and one inactive (non-cephalic) electrode. which exception of a Cz reference, where Cz is used as a reference site, but is technically active. A bipolar montage consists of electrode groupings which are both active (scalp) electrodes.

N is for notch, or 60hz filter! An active setting used to filter out fast, 60cps artifact caused by electrical interference. When notch filter is on, it can rid 60Hz artifact ( very fast, black “fuzzy” recording), but it can attenuate frequencies as low as 10Hz. Source of artifact should be eliminated ( if possible) before the notch filter be used. Caused by: recording in an electrically hostile environment, a bad ground electrode, a bad scalp or reference electrode, high impedances, bad jackbox.

O is for OIRDA Occipital Intermittent rhythmic delta activity. This abnormal slowing recorded from the posterior head regions. Usually after a stroke or trauma.

P is for parameters The low filter will attenuate slower frequencies, but will not effect faster frequencies . The normal low filter setting is 1Hz. A higher LFF setting of 3Hz or 5Hz will attenuate greater amounts of slowing. The high frequency filter will attenuate higher frequencies, but will not effect the slower ones. A normal HFF filter setting is 70Hz. A lesser HFF setting of 35Hz or 10Hz will attenuate a greater amount of faster activity.

Parameters continued……. A normal paperspeed is 30mm/sec or 10sec/pg. To enhance slowing, use a slower paperspeed of 15mm/sec or 20sec/pg. In order to “spread out” faster frequencies to localize a abnormality, or to count out 60Hz contamination, increase the paperspeed to 60mm/sec, or 5sec/pg.

P also stands for polarity If input 2 is more positive than input 1, pen deflection will go up. If input 2 is more negative in relation to input 1, pen deflection will go down.

P is also for Photic Stimulation Activation procedure consisting of flashes of light focused on the pt’s facial region at selected frequencies. May produce a driving response, which is a normal variant, identified as sinusoidal waveforms produced in the posterior head regions that are half, equal to, or double the rate of the photic speed. May also produce abnormal responses: - Asymmetrical driving response ( driving response over only one side for posterior head region - Photo-Paroxysmal Response ( Generalized spike/wave discharges that often outlast the the photic stimulation. No clinical signs. - Photoconvulsive Response ( Pt sent into a T/C seizures that also outlast the photic stimulation.

Q is for Quiescence Another term for inactivity or quietness. Used to describe the EEG of a neonate born at or before 22 weeks conceptual age.

R is for RECORD Record must have be acquired within 12 months of the exam. Records must contain a minimum of 16 channels. Records should not be indicative of: ECI, status epilepticus, surgical monitoring, ambulatory, long term epilepsy monitoring, neonatal recordings. Record should contain at least one period of eye opening and closing.

S is for Sleep In a 1947 study of 500 cases of epilepsy, epileptic activity was more that twice as likely to occur during sleep. This is especially true in cases of temporal lobe epilepsy. Stage I characterized by attenuation of the background, slow rolling eye movements. Stage II defined by sleep spindles Stage III defined as 20-50% of the record

Trace Alternant

T is for Time Record should be a minimum of 20 minutes or 120 pages long no including calibration and bio-calibration

BREECH rhythm is not an acceptable abnormality. U is for Understand BREECH rhythm is not an acceptable abnormality.

V is for Vertex Sharp waves Appear between 3-6 months of life. Moderate to high amplitude, sharp and biphasic waves lasting 100-200msec in duration. Usually a surface negative wave, followed by a positive component.