I've written about the growth of this activity or hobby but here is a recent good article on it. The author experimented with different techniques and recorded her brain waves to test how effective it really was.
I've since read elsewhere about her and how she had embraced the practice after doing the article on it.
Excerpts...
Meditation masturbation goes by many different names, each with a variety of approaches: erotic meditation, orgasmic meditation, tantric masturbation. All fall under the umbrella of mindful sex, an increasingly popular branch of mind-body awareness centered around sexuality, intimacy, and pleasure.
Meditation and masturbation might sound like strange bedfellows. But actually on both physiological and psychological levels, the two go together like peanut butter and jelly. At a time when we're all looking for stress-relieving solo activities to do from the safety of our homes, a relaxing self-love session comes with numerous health benefits too.
Link:https://mashable.com/article/masturbation-meditation-orgasmic-mindful-sex/