Free will is the concept that humans are able to control their behaviors independent of their biology or environment. Free will is often correlated with the concept of a human soul that is separate from the body and mind.

Determinism is the idea that every phenomenon in the universe, down to the location of a subatomic particle, is caused by preceding factors. Determinism incorporates the nature of change, the unpredictability of chaoticism, and the impacts of meta-cognition—or thinking about thinking.

An electroencephalogram (EEG) is a scan that uses electricity to measure brain activity. The process involves attaching electrodes to the skull or inserting them into the brain using probes to measure activity.