What is F3 Zone?
The F3 zone is an electrode position in the international 10–20 EEG system, located over the left Dorsolateral Prefrontal Cortex (DLPFC). It is a primary target for tDCS and other neuromodulation protocols aimed at cognitive focus, working memory, and executive function.
Why F3
- •Left DLPFC — implicated in verbal working memory, planning, and cognitive control
- •Standard target — widely used in research for depression and cognition
- •Reproducible — 10–20 system allows consistent placement across sessions
Why does the F3 Zone matter?
The F3 zone matters because it is a standard reference point for placing sensors over the left frontal region of the head. A fixed, named location lets researchers and clinicians compare recordings or stimulation targets across people and studies.
F3 sits roughly over the left dorsolateral prefrontal cortex, a region involved in working memory and emotional regulation. For that reason it is often used in EEG research on frontal activity and as a practical landmark for brain-stimulation targeting. Because head shapes and brain anatomy vary, the underlying brain area is only approximately the same from person to person.
How is the F3 Zone measured?
The F3 zone is located with the international 10-20 system, which uses skull landmarks rather than fixed distances. Technicians measure from the nasion (the bridge of the nose) to the inion (the bump at the back of the skull) and between the ears, then place electrodes at set percentages of those distances.
In practice, caps with pre-marked positions are common. When precise targeting matters, for example in stimulation research, neuronavigation based on a person's own MRI scan locates the target more accurately than scalp measurements alone.
In ONDA Life
The Electric Medicine article describes tDCS protocols targeting the F3 zone for cognitive focus.