American Clinical Neurophysiology Society Guideline 2: Guidelines for Standard Electrode Position Nomenclature

Vocabulary flashcards based on the American Clinical Neurophysiology Society guidelines for EEG electrode positioning.

Electroencephalography (EEG)

A neurophysiologic measurement technique to record electrical activity of the brain.

10-20 System

The international standard for recording routine scalp EEG, using 21 electrodes placed at relative distances (10% or 20%) between cranial landmarks.

10-10 System

A modification of the 10-20 system that provides nomenclature guidelines for additional electrodes, improving spatial resolution.

Spatial Resolution

The ability to distinguish between closely spaced features in a neuroimaging study; higher electrode density improves spatial resolution in EEG.

Anteroposterior Plane

Relating to the direction from the front to the back.

Coronal Plane

An imaginary plane that divides the body into front and back sections.

Sagittal Plane

An imaginary plane that divides the body into left and right sections.

Alphanumeric Nomenclature

A naming system using both letters and numbers to designate electrode positions.

Electrode Position

The specific location on the scalp where an EEG electrode is placed.

Cranial Landmarks

Reference points on the skull used to determine electrode placement.

Interictal Epileptiform Discharges

Abnormal electrical activity in the brain observed between seizures.

Ictal EEG Onsets

The beginning of seizure activity as recorded on an EEG.

Temporal Lobe Epilepsy

A type of epilepsy originating in the temporal lobe of the brain.

Mesial Frontal Lobe Epilepsy

A type of epilepsy originating in the mesial frontal lobe of the brain.

Epileptic Focus

The specific location in the brain where seizures originate.

Source Localization

A method used to determine the origin of electrical activity in the brain.

Electrical Source Imaging

A technique that creates images of the electrical activity in the brain.

Headbox

The part of an EEG machine where electrodes are connected.

Alpha

A brain wave in the 8-12 hz range.

Beta

A brain wave in the 12-30 hz range.

Theta

A brain wave in the 4-8 hz range.

Delta

A brain wave under 4 hz.

Frequency

The number of cycles per second.

Amplitude

The magnitude of an electrical signal.

Fp1/Fp2

Frontopolar electrodes in the 10-20 system.

O1/O2

Occipital electrodes in the 10-20 system.

T3/T4

Temporal electrodes in the 10-20 system (replaced by T7/T8 in the modified 10-10 system).

T5/T6

Temporal electrodes in the 10-20 system (replaced by P7/P8 in the modified 10-10 system).

T7/T8

Temporal electrodes in the 10-10 system, replacing T3/T4.

P7/P8

Posterior temporal electrodes in the 10-10 system, replacing T5/T6.

AF

Anterior Frontal electrodes in the 10-10 system.

FT

Frontotemporal electrodes in the 10-10 system.

FC

Frontocentral electrodes in the 10-10 system.

TP

Temporoparietal electrodes in the 10-10 system.

CP

Centroparietal electrodes in the 10-10 system.

PO

Posterior Occipital or Parieto-occipital electrodes in the 10-10 system.

AFz

Anterior Frontal midline electrode.

POz

Posterior Occipital midline electrode.

F9/F10

Electrode positions 10% inferior to the standard frontotemporal electrodes.

T9/T10

Electrode positions 10% inferior to the standard temporal electrodes.

P9/P10

Electrode positions 10% inferior to the standard temporal/parietal electrodes.

F11

Electrode positions 10% inferior to ninth row frontal electrodes.

FT11

Electrode positions 10% inferior to ninth row frontotemporal electrodes.

T11

Electrode positions 10% inferior to ninth row temporal electrodes.

TP11

Electrode positions 10% inferior to ninth row temporoparietal electrodes.

P11

Electrode positions 10% inferior to ninth row parietal electrodes.

PO11

Electrode positions 10% inferior to ninth row posterior occipital/parieto-occipital electrodes.

O11

Electrode positions 10% inferior to ninth row occipital electrodes.

F12

Electrode positions 10% inferior to tenth row frontal electrodes.

FT12

Electrode positions 10% inferior to tenth row frontotemporal electrodes.

T12

Electrode positions 10% inferior to tenth row temporal electrodes.

TP12

Electrode positions 10% inferior to tenth row temporoparietal electrodes.

P12

Electrode positions 10% inferior to tenth row parietal electrodes.

O12

Electrode positions 10% inferior to tenth row occipital electrodes.

Nasopharyngeal Electrodes

Electrodes placed in the nasal cavity to record EEG activity.

Sphenoidal Electrodes

Semi-invasive electrodes used for precise localization in temporal lobe epilepsy evaluation.

American Clinical Neurophysiology Society (ACNS)

Organization that provides guidelines and standards for clinical neurophysiology.

Encephalopathy

A general term describing brain disease, damage, or malfunction.

Generalized Abnormalities

Abnormal electrical activity seen throughout the brain.

Psychogenic Events

Events or seizures that have a psychological rather than a neurological origin.

Focal Epilepsy

Seizures originating in one specific area of the brain.

Long-Term Video-EEG studies

Continuous monitoring of brain activity and video recording of patient behavior over an extended period.

Ambulatory EEG

An EEG recording conducted while the patient is mobile and performing daily activities.

Interictal

The period between seizures.

Ictal

Refers to the period during a seizure.

EEG Artifacts

Electrical signals or interferences that are not of cerebral origin.

Pre-Surgical Evaluation

Assessment done to determine the area of the brain causing seizures prior to surgery.

Clinical Context

The relevant circumstances surrounding a patient's condition or situation.

Semi-invasive

A procedure that involves minor penetration into the body.

Non-invasive

A procedure that does not involve breaking the skin or entering the body.

Electrode Impedance

Resistance to the flow of electrical current.

Differential Amplifier

A type of electronic amplifier that amplifies the difference between two input voltages.

Common Mode Rejection

The ability of a differential amplifier to reject signals that are common to both inputs.

Montage

A particular arrangement of EEG electrodes.

Bipolar Montage

Each channel represents the difference between two adjacent electrodes.

Referential Montage

Each channel represents the difference between a specific electrode and a common reference electrode.

Average Reference Montage

A referential montage in which the reference is formed by averaging all the electrodes.

Laplacian Montage

A montage that emphasizes local activity.

Sensitivity

The ratio between the input signal amplitude and the output writing deflection.

High-Frequency Filter (HFF)

An electrical filter that attenuates high-frequency signals.

Low-Frequency Filter (LFF)

An electrical filter that attenuates low-frequency signals.

Notch Filter

A filter that attenuates a narrow band of frequencies