Dr. Cheryl Fraser: How To Have Better Sex & Intimacy (Archived Interview)
Note from the archive: almost nothing of the original interview survived in the extracted page. What remained was site furniture and promotional material rather than the conversation itself. The one piece of genuine background worth keeping concerns the audio technique the page was built around.
The effect behind that technique traces back to 1839 and a German physicist named Heinrich Wilhelm Dove. He was a Fellow of the Royal Society and ran the Prussian Meteorological Institute, and he was the first to describe what happens in human perception when each ear receives a slightly different tone.
Dove's observation sat largely unused for more than a century. It was only across the 1950s through the 1970s that engineers turned the idea into working audio technology. Several people have since claimed credit for that later development, but the original discovery belongs to him.
In more recent decades the same principle has been applied to mindfulness and relaxation practice, the premise being that a particular auditory stimulus can nudge brainwave activity toward a calmer state. Research on brainwave entrainment and its psychological effects has been published and can be found through databases such as PubMed.