EEG Outside the Lab: Mobile Cognition and Ecological Validity

Why leave the laboratory?

Laboratory experiments control everything: posture, light, noise, the task. That control is what makes them rigorous, and also what limits them. What happens in a quiet room does not always happen under real pressure.

Researchers have argued for a mobile cognition approach, which studies the brain while people move and act in real environments, so that findings describe cognition as it is used ^[1].

What mobile EEG has shown

In an early demonstration, a low-cost, small and wireless EEG recorded a classic brain response, the P300, while participants walked outdoors on a university campus ^[2]. Measuring the brain outside the lab was possible, with care.

Work on mobile brain and body imaging goes further and records brain activity together with body movement, to understand cognition in action ^[3].

The challenges

• Movement. Muscles, cables and electrodes move with the body and add artefacts to the signal; recording head and body movement helps set them apart ^[3].
• Context. In the real world, the task is not controlled: events, timing and environment must be recorded with the brain signal.
• Synchronisation. Brain, heart, movement and task data must share one clock to be read together.

Good practice

• Keep the raw recording, with quality markers, alongside any derived indicator.
• Run the same reference protocols, such as resting baselines, before the real task, to compare participants and sessions.
• Export in open formats, such as EDF+ for brain signals and CSV for tables, so the analysis can be checked.

How SPARK approaches it

SPARK records brain activity, heart, head movements, behaviour and task data together in the real situation, on one clock, with the quality of each channel checked. Recordings are exported in EDF+ and CSV for analysis in the researcher's own tools.