Common EEG Artifacts & Their Identification Flashcards
Name 7 Common EEG artifacts
Muscle, Eye Movement, Electrode Popping/Movement, Environmental Noise, Electrode Impedance, Sweating/Salt Bridge, Electrical Interference
What are examples of muscle artifact?
eye blinks, eye movement, jaw clenching, facial movements, body twitches
True/False - muscle artifacts appears as low amplitude wave forms
False
How do muscle artifacts appear as waves?
As sharp, spiky waves that coincide with the timing of the muscle activity
What is the fix for muscle artifacts?
Try to calm the patient. Change the high frequency to check if the activity attenuates and make notations
What causes eye movement artifacts?
Eye movement artifacts are caused by rapid eye movements (saccades) or slow eye drifts during wakefulness or rapid eye movement (REM) sleep
How do eye movement artifacts appear as waves?
They appear as slow waves or sharp deflections, often with horizontal or vertical orientation
Where are the eye movement artifacts commonly seen?
In the frontal or prefrontal electrode channels
When does electRode popping (or movement) occur?
When electrodes become loose resulting in intermittent loss of contact or displacement from the scalp
How do electrode popping or movement manifest as waves?
As abrupt signal loss or fluctuating amplitudes often affecting specific channels
What is the fix for electrode popping?
Rescrub or reapply electrode or replace if necessary
What are the external source types that cause environmental noice artifacts?
Electrical equipment, power lines, electromagnetic fields, or radio frequency
Describe the environmental noise artifacts
They can cause rhythmic or irregular disturbances across multiple channels and often appear as high frequency, low amplitude waves or irregular patterns unrelated to brain activity.
What is the fix for environmental noise artifacts?
Check connection of cables to amplifiers
What is electrode impedance?
Refers to the resistance encountered between the electrode and the scalp which affects the quality of the recorded signals
What is the fix for electrode impedance issues?
Rescrub and reapply electrode - or replace if necessary
What is common mode rejection?
It refers to the ability of an EEG system to reject unwanted signals that are present in equal measure at multiple electrodes
How does the wave form look with sweating or salt bridge?
Inconsistent, erratic or attenuated signal
What is the fix for sweating (or salt bridge) issues?
Clean between electrodes with alcohol and or turn temperature in the room down
What is an electrical interference artifact.
Results from nearby electronic devices, power sources or faulty grounding
How do electronic interference artifacts appear?
As regular, rhythmic, or repetitIve patterns across multiple channels manifesting as sharp waves, spikes for oscillations.
What is the fix for electrical interference?
Let Pt and family know that personal devices may not be charging when in contact with patient or anything patient is sitting or lying on
