Intermediate
Technical
IVT
lambda wave
A positive sharp transient occurring over occipital regions during visual scanning and saccadic eye movements.
Full Definition
Lambda waves are normal EEG phenomena appearing as positive sharp waves over the occipital cortex, typically bilateral but often asymmetric. They occur during active visual exploration, particularly when examining complex visual patterns or during reading. The morphology resembles the Greek letter lambda, giving the wave its name. These transients are eye movement-related artifacts that can be eliminated by having the patient close their eyes or fixate on a stationary target.
Usage
Usage note: Should be identified as normal variant, not pathological activity.
In Context
- "Lambda waves were noted over both occipital regions during the eyes-open condition while the patient was looking around the room." — EEG interpretation
Don't confuse with
occipital spikes
positive occipital sharp transients