Lateral Gaze Artifact

Lateral gaze artifacts in EEG recordings occur during eye movements towards the sides.

Nature of Lateral Gaze Artifacts:

o Lateral gaze artifacts are produced by eye movements towards the sides, resulting in specific patterns in the EEG.

o These artifacts are dependent on conjugate gaze, where each eye's dipole contributes to the artifact.

2. Characteristics:

o Lateral gaze artifacts typically exhibit positive and negative phase reversals at specific electrodes corresponding to the direction of gaze.

o The field of lateral gaze artifacts is maximum across the temples and frontal poles, with a frequency usually less than 1 Hz.

o The amplitude of lateral gaze artifacts is low, resembling an unstable baseline for the superimposed EEG activity.

3. Differentiation:

o Lateral gaze artifacts can be distinguished by their waveform characteristics, which have a more abrupt transition between positive and negative slopes compared to blinks and eyelid flutter artifacts.

o Specific movement features, such as the direction of gaze and the resulting phase reversals at electrodes, help differentiate lateral gaze artifacts from other ocular artifacts and EEG patterns.

Understanding the characteristics and differentiation of lateral gaze artifacts is essential for accurate EEG interpretation, as these artifacts can mimic abnormal brain activity if not properly identified and distinguished from genuine EEG patterns.

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