[waverider]

I thought I read here somewhere that square waveform is not recommended for audiostrobe. Did I get that right, and if so why?

[admin]

I haven't read this. In fact most vendors and audiostrobe CDs use square waves, because they won't have the same issues with volume/brightness that sine waves can have. But, sine waves are more relaxing. We use sine waves in all of our relaxation sessions, but for beta/SMR sessions we use square waves.

Square wave photic stimulation tends to produce harmonics in the brain. Basically this means that if you stimulate 10 hz square waves with LED glasses, it may also stimulate 20,30,40. This is great for cognitive enhancement sessions, but not the effect you want for most relaxation sessions, unless you're going for more of an Anna Wise type scenario, which I know you might be interested in waverider

Adam

[waverider]

admin, on Dec 1 2006, 11:58 AM, said:

I haven't read this. In fact most vendors and audiostrobe CDs use square waves, because they won't have the same issues with volume/brightness that sine waves can have. But, sine waves are more relaxing. We use sine waves in all of our relaxation sessions, but for beta/SMR sessions we use square waves.

Square wave photic stimulation tends to produce harmonics in the brain. Basically this means that if you stimulate 10 hz square waves with LED glasses, it may also stimulate 20,30,40. This is great for cognitive enhancement sessions, but not the effect you want for most relaxation sessions, unless you're going for more of an Anna Wise type scenario, which I know you might be interested in waverider

Adam

OK, thanks, Adam. I'm doing my .5 to 40 hz rapid ramp or random sessions right now, so square waves might be just what I'm looking for.

Why do square waves produce harmonics but not sine, and why doesn't this same principle apply to tones?

[admin]

Sine waves are pure, and pure waves don't produce harmonics. I'm not sure why the same effect doesn't occur with tones, probably because of the comparative size of the visual cortex (much larger).

Adam

[waverider]

admin, on Dec 1 2006, 12:09 PM, said:

Sine waves are pure, and pure waves don't produce harmonics. I'm not sure why the same effect doesn't occur with tones, probably because of the comparative size of the visual cortex (much larger).

Adam

OK

As for tones, isn't it true tho that entraining to freq x will also entrain to 2x and reduce 1/2x?

[admin]

Reduction yes, to an extent, but I've not heard that a 2x harmonic gets stimulated as well. It is certainly possible though

Adam

[USpacebreaker]

Quote

Reduction yes, to an extent,

Adam, could you tell us where you got this information. I remember reading something about this a while back but have forgotten where I came across it. Thanks.

[admin]

To best honest I've forgotten where I read it. It could have been in Siever's book, though I do remember he mentions that in some cases during alternating sessions you can see a subharmonic *increase*.

At any rate, I've seen reduction happen during our EEG work. I don't think it was 2 x in particular, just a general reduction of frequencies outside of the stimulus, particularly slow waves when using beta.

Actually come to think of it I do occassinally see a harmonic of 20 hz using 10 hz audio stimulation. But, this is rare, and could have been unrelated.

Adam

[waverider]

admin, on Dec 1 2006, 01:22 PM, said:

To best honest I've forgotten where I read it. It could have been in Siever's book, though I do remember he mentions that in some cases during alternating sessions you can see a subharmonic *increase*.

At any rate, I've seen reduction happen during our EEG work. I don't think it was 2 x in particular, just a general reduction of frequencies outside of the stimulus, particularly slow waves when using beta.

Actually come to think of it I do occassinally see a harmonic of 20 hz using 10 hz audio stimulation. But, this is rare, and could have been unrelated.

Adam

My understanding was that when people talk about theta reduction sessions they entrained to 2x the freq that they desired to reduce.

My idea about also entraining to 2x the frequency came from the Awakened mind session in NNS - thought it said so there.

[admin]

Ah, you are right: audio "alternating" methods like auto-pan have indeed been known to produce harmonics. That was originally implemented in the AM session, though it looks like it was taken out later, and the description wasn't updated. I need to make an updated version of that, using audiostrobe and NP2.

Adam

[victor]

Square wave photic stimulation tends to produce harmonics in the brain. Basically this means that if you stimulate 10 hz square waves with LED glasses, it may also stimulate 20,30,40. This is great for cognitive enhancement sessions, but not the effect you want for most relaxation sessions, unless you're going for more of an Anna Wise type scenario, which I know you might be interested in waverider

Adam
[/quote]

Hi Adam,

What do you mean on "Anna Wise type scenario" ?