We don't know how it happens, but we know it does. The individual cells change in their absorption of specific neural transmitters. We need to assess in the same state or context as we teach. My suspicion is that students learn a great deal in school, but they are tested in a way that can make them feel like they don't know anything. The learning often takes place in an aura of playfulness and enjoyment.
Performance often takes place in an aura of stress and strain.
It seems plausible then to rehearse the performance in a stressful state so that students can become adapted to that kind of pressure. Students can learn to retrieve information under a stress if they are taught. Assessment must consider these aspects to be authentic. We haven't found as much research as I would like in knowing how the brain is shaped through a person's interaction with technology. There is an impact, but we don't know all the clues.