A reference frame gives each recorded landmark a consistent spatial context. The nasion, preauricular points, and electrode positions can therefore be represented as coordinates relative to the same frame rather than as isolated locations. This organization allows software to relate measurements from the subject’s head to other spatial datasets and supports more reproducible anatomical alignment.
These anatomical landmarks provide recognizable points for establishing the subject’s head geometry. Recording them alongside EEG electrode positions creates a spatial relationship between electrode locations and the individual’s anatomy. That relationship is important when measurements are later aligned with magnetic resonance images, because the electrode data can be interpreted within the subject-specific head configuration.
Neural source estimates depend partly on how accurately recorded signals are related to anatomy. Digitized electrode coordinates provide spatial information that can be co-registered with magnetic resonance images, linking signal measurements to the individual head structure. This anatomical correspondence strengthens the spatial basis for interpreting where neural activity may originate.
The workflow begins by positioning a handheld stylus or tracked sensor at selected anatomical landmarks and EEG electrode sites. The device records each point in three dimensions relative to a reference frame. Software then converts those measurements into spatial data, which can be used for electrode co-registration with magnetic resonance images and subsequent neuroimaging analysis.
It captures the three-dimensional positions of both anatomical landmarks and electrode locations. These measurements preserve the spatial relationship between the recording setup and the participant’s head anatomy, rather than retaining only electrode identities or their intended arrangement. The resulting coordinates provide subject-specific information for aligning EEG measurements with anatomical and neuroimaging data.
It is especially useful when researchers need to connect EEG recordings with individual anatomical data. By digitizing head landmarks and electrode positions, they can support co-registration with magnetic resonance images and obtain a more anatomically informed interpretation of recorded signals. The approach is therefore relevant to studies requiring precise alignment and reproducible estimates of neural source locations.