Homeopathic AVS

First, let me make it perfectly clear that I think the debate over the scientific basis for homeopathy is a completely done deal. There is no scientific basis. Second, let me make it perfectly clear that I have profound respect for the placebo effect, which I believe is used as a catch-all for a complex blend of as-yet unrecognised mechanisms including the ability to consciously alter outcomes, past and future, by thought.

I’ve taken every chance that’s come up to have a listen to brainwave entrainment targeted content. So far nothing that has claimed to have potentially brainwave stimulating signals has failed to deliver to that point. However, in many cases I find myself well into a session without experiencing any of the sensations I associate with changes in my dominant mental state. I’ve learned that there are some very specific things that are more likely to nudge my brain one way or ‘tuther, some that will guarantee beta-grade attention every time – even if they’re in the middle of a very successful delta passage and some that are just ear-candy.

In every case I try to spend a good part of my time listening to the structure and a good part hearing the flow of the session. Swapping back and forth between subject and analyst all the time ruins the outcome for both.

The conspicuous difference between sessions that exhibited a high level of perceived effectiveness and those that did not was simply the degree to which stimulus signals could be differentiated in the overall soundscape.

To establish something of a benchmark, I ran informal EEGs of twenty minutes of a track that I find pleasant but not perceptibly psychoactive, and one which blows my socks off every time. Electrodes were placed over the right temporal region and over the centre of the frontal lobe. The results were unsurprising. One had almost no correlation in activity between the temporal and the frontal lobes, meaning, in my experience, that consciousness is still doing pretty much whatever it wants – a good meditator would have probably been showing a load of delta regardless of the session intent. The other showed near perfect correlation between regions with the temporal lobe showing extremely accurate correspondence to the stimulus, and the frontal showing regular dominance at the targeted frequencies.

“Where’s the pics,” you may say. Indeed, why don’t I put up screencaps of the heroic moment when EEG proves that one thing is better than another? Two reasons. First, my recordings are completely meaningless to anyone but me – I have no observer to record the times of blinks or body movements and I also take into account how I was feeling or what I was thinking, to have a sense of when I was with the session and when I was not. Second, a screen cap can be found or made to demonstrate absolutely anything. If anyone feels inclined to replicate the experiments, and gets substantially different results, I’d be more than pleased to repeat mine to a higher standard.

Having established that the principle was sound, I prepared a set of very simple 10 minute audio-only sessions. The variables were volume of unentrained noise, volume of background music (from Thoughtsounds), volume of a sine shaped iso track, and depth of entrainment of the iso track.

To cut a long story short…

If you have to listen to detect the beat, then the active ingredients are lost – you are in the realm of homeopathic AVS. In this realm dependence on current science is suspended. For example, it’s easily demonstrated that binaural beats do not stimulate cortical entrainment. They are, however, supported by a huge volume of favourable testimony. For some people, binaural based tracks are effective. For the purposes of this discussion, let’s define “effective” as meaning that the track delivered the effect that the user sought. Homeopathy is effective on the same basis.

Once the active ingredients kick in, that is to say, as soon as you can hear without effort sounds at the targeted frequencies, as soon as the pattern can be plainly heard and seen in the temporal EEG, the effectiveness, both perceived and as measured by correlation between temporal and frontal activity, increases with the attention grabbing character and volume of the beat.

The most useful thing a lot of tracks do is use lots of noise, either synthetic brown, pink or white, or natural in the form of wind, rain, running water, etc. Unmodulated noise, noise with no added stimulus signal, does a wonderful job of disentraining the whole system. Once disentrained, once the whole cortex is nice and pliable, it’s much easier to induce entrainment. Beats submerged in noise are more effective than beats submerged in any more structured sound. Adding structured sound (music) is a very good way of reducing low alpha, theta and delta response.

I’ve talked about the relative effectiveness of different stimulus types elsewhere, and I did nothing in this series of trials to add to or diminish my earlier impressions. These trials used sine shaped stimulus, which is the gentlest.

The “note to self” I take from all of this is that I need to be highly cognisant of the diversity of interests in AVS. AVS is, to me, the most personal of media. We’re inviting another person to have privileged access to our mental processes. We each do so to fulfil some desire. If the desire is to relax, then a well composed piece of ambient music may well be a better choice than many of the available relaxation-targeted entrainment tracks. If a specific technique or therapy is optimised by the brain being dominated by a particular rhythm, then the most effective stimulus will be a 100% modulated pulse, almost square, but with leading and trailing angles and corners shaped to minimise harmonics, about 20% duty cycle, filled with a high pitch or white noise. “Most effective” truly is a bitter pill! There’s a lot of reasons to choose any point on the spectrum – no intent or measure of outcome has any intrinsic superiority.

To be clear, I am talking here of audio-only sessions combining stimulus signals with natural or ambient soundscapes. Things change a great deal when all attempts to hide the beats are given up.

Cheers,
Craig

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