Learn Essentials of Adult Electroencephalography (EEG)

Learn the basics of EEG waves, including waveform types, frequency bands (delta, theta, alpha, beta), amplitude in microvolts, distribution patterns, and how montage affects voltage.

Alpha rhythm appears as sinusoidal waves in the awake EEG, best seen posteriorly with eyes closed, attenuated by eye opening and mental activity, typically under 50 microvolts and 8–13 Hz.

Discuss mu rhythm, 8–10 Hz alpha pattern attenuated by movement and unresponsive to eye closure. Note beta activity above 13 Hz with frontal prevalence and lambda waves as occipital responses.

Explore ocular eeg artifacts, including blink and lateral gaze, through polarity rules and eyes as dipoles. Learn how Fp1, Fp2, F7, and F8 detect them.

Identify common EEG artifacts such as electrode pop artifact, salt bridge, EMG, sweat, and cardiac artifacts; understand bipolar and referential montage effects and impedance checks for artifact reduction.

Compare awake and sleep EEG features, highlighting alpha dropout and slow rolling eye movements, vertex waves, posts, k-complexes, and sleep spindles across sleep stages.

Explore sleep stages in EEG via polysomnography, covering REM and non-REM stages N1, N2, N3, with alpha, theta, delta rhythms, spindles, K-complexes, vertex waves, and sawtooth waves.

Explore activation procedures in adult EEG, including hyperventilation, intermittent photic stimulation, and sleep deprivation, to boost diagnostic yield and identify photo driving, myogenic, and convulsive epileptiform responses.

Explain abnormal EEG concepts, including epileptiform activity, terminology, sharp waves, spikes, poly spikes, and spike-and-wave complexes, and define normal versus abnormal EEG with polarity principles.

Explore how source localization in EEG localizes seizure focus in epilepsy using phase reversal and end of chain phenomena in bipolar montage, and referential montage comparisons.

Focal epileptiform activity presents as spikes or sharp waves—asymmetric, multi-phased with an aftergoing slow wave—detected across Silverman's electrodes; temporal lobe epilepsy is the most common focal epilepsy in adults.

Explore generalized epileptiform activity, its spike‑and‑wave discharges and patterns, distinguish it from focal activity, and review idiopathic generalized epilepsy syndromes such as childhood absence, juvenile myoclonic epilepsy, and gtcs-only epilepsy.

Examine abnormal slow waves and amplitudes in EEG, including generalized and asynchronous slow waves, delta activity, PDR, Ferda, amplitude asymmetries, and breech rhythm, linked to encephalopathy and structural lesions.

Explore abnormal EEG patterns—pleads, periodic sharp wave and generalized complexes, triphasic waves, burst suppression, and alpha and beta coma—and link them to stroke, encephalitis, Creutzfeldt-Jakob disease, hepatic metabolic encephalopathy.

Identify normal EEG variants including wicked spikes, small sharp spikes of sleep, six hertz phantom spike and wave, and 14 and six hertz positive spikes, and misreading as epileptiform discharges.

Analyze a normal EEG report, covering personal particulars, procedure, observations, and impression from a 16-channel 1020 system. Note the alpha rhythm and absence of epileptiform discharges or focal abnormalities.