It’s not hard to induce gamma oscillations naturally: Our neurons achieve such synchrony when we are learning, paying attention or engaging our short-term memory.

Research has found that when parties are getting along, they tend to mimic each other’s subtle speech patterns: “language synchrony,” as it is known.

Bedtime in darkness is complementary to morning light but without the regular morning 'zeitgeist' signal, synchrony to the outside light dark cycle may not occur.