One of the brutal reviews I stumbled on looking at his Goodreads reviews.
UPDATE 12/17: More research into ASMR has further rendered this book not useful. Studies published this year seem to link the ASMR phenomena to synesthesia, a condition where one or more senses blend together (tasting colors, smelling sounds, feeling ideas, etc.). Researchers looking at the brains of those who experience ASMR found a blending together of areas of the brain that are typically quite separate in those who don't experience ASMR. This blending is also seen in the brains of those with synesthesia.
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Unfortunately, any value this work may have had at one point has been quickly outdated due to the preliminary results of scientific research into the ASMR phenomenon.
This is a very short work at 30-some pages and flits over the author's thoughts (typically dismissive) on the varying possible causes of, or basis for, ASMR. It's clear the author very much wants ASMR to be based in occult experience and this, unfortunately, informs and clouds his ability to keep an open mind (how ironic, considering the occult bent).
We reach the end of the potential usefulness of this work within a few pages, where the author dismisses the potential link between ASMR and meditation. In fact, he later goes on to assert that ASMR wouldn't be indicated in meditation because ASMR uses only sound (which itself is false, as exhibited by the preponderance of ASMR videos that use only touch as triggers, often called "personal attention", i.e. scalp massage, face brushing, hair play, and so on. These are the most popular videos, indicating it's attention, not sound, that's often the key. The author's own experience of ASMR has drastically colored his conclusions) and silence is required for meditation.
Why does his dismissive attitude toward ASMR as meditation kill the usefulness of this work? Because the preliminary research into ASMR showed that when you put a subject into an MRI machine and trigger their ASMR, the part of the brain that lights up during meditation is exactly what lights up in the ASMR subject. While research into ASMR is in its infancy, it looks like it might just be that what some people have to devote large amounts of time (and focus and stillness) to achieve can be achieved by others through simple, quick, and readily accessible ASMR triggers.
So while the author goes on to link ASMR to speaking in tongues, astral travel, psychotropic use* (the author experienced an ASMR-like tingling during such use so naturally there must be a link), kundalini, and so on while immediately dismissing a very real link.
One thing I found frustrating is the author's idea that ASMR triggered by touch isn't real ASMR, only that triggered by sound, saying he doubts touch-triggered ASMR would begin in the head like sound-triggered (he makes this assumption because he doesn't experience it as such himself). There are many, many people out there who would love to tell him how wrong he is (a very quick internet search could have cured him of this assumption). This is frustrating because in the beginning of the work he expresses his own frustration with people who refute ASMR because they don't experience it themselves, and yet the author goes on and does that exact thing. So not only do those who experience ASMR have to deal with the denial of those who don't experience it, they also have to worry about some sort of ASMR purity concept within the community.
The one thing he does get right but touch on too superficially for a text of this title is the amount of ASMR roleplay videos that have an occult theme (witches, healers, reiki, tarot readers, etc.). The question of why ASMR lends itself to this sort of theme is one that, I think, deserves more thought. Although he does mention that this use of occult images help soften their "evilness" to a wider audience that is often fearful of such things, which is a potentially important observation that I had overlooked myself.
Now, what I would like to see is a book discussing how to use the ASMR phenomenon in occult/spiritual practices, which I mistakenly thought this book would touch on. In all, this work feels like an outline for a larger work that will need an more unbiased eye and more updated research.
*From the book: "...a tingling sensation so much similar to that of ASMR that I can't help but presume that the muscimol in the mushroom triggers the same mental pathways that ASMR does, albeit doing so as a chemical rather than a trigger which is purely derived from sound." Also notice that "purely derived from sound" idea again.