I am wondering if there is anything published proposing a neurological explanation for the vibrations in sensory perceptions perceived through meditation.

https://www.lesswrong.com/posts/QjoTFHzvrxQg9A6j3/meditation-insight-and-rationality-part-2-of-3


Thanks in advance ...

There are three speeds of mind, speed of thought, attentional system and awareness.
A&P/second jhana makes the senses "vibe". It's because you're in the attention speed.

Look into the book
Pointing Out the Great Way
By Daniel P. Brown~D

I'm doing some review of DhO posts related to vibrations.  This came up in my search, and I wanted to respond to it.

The most obvious explanation for vibration perception in meditation is that people are directly sensing their brainwaves and central nervous system (CNS) signals.  This is the case for me: I can see some frequency patterns in the phosphenes, and feel others in my body during practice (as corroborated by evidence from some EEG experiments).  Anecdotally, I have a friend who can hear her brainwave vibrations in what she calls the "crickets", the audible high-frequency buzz of the nervous system activity. It's likely that many of the meditators featured in Paul Dennison's Jhāna Consciousness research are experiencing something similar.  It seems that Daniel Ingram can see (and perhaps feel?) his brainwaves as well during certain types or stages of practice.  On p. 214 of MCTB2, when discussing the Dark Night, he provides some specific frequency data; earlier (p. 188), he writes, "It is also very likely that one day EEG researchers will find remarkable parallels between the frequency and phase of flickering kasina images and some of the signals seen on an EEG, providing measurable insights into the workings and physiological correlates of attention itself".  Direct sensation of CNS activity is a simple and straightforward explanation, because CNS oscillations are well-established scientific phenomena.  There is a lot of current research into the neurological correlates of meditation, including different vibration profiles for different sorts of practices.

(Note that I interpret "vibration perception" literally and simply, as a light periodically brightening and dimming, a sound getting periodically louder or softer, a felt sensation periodically tensing and relaxing, etc.  "Vibration" is often used more figuratively in experiential descriptions.  For example, Daniel writes on p. 23 of MCTB that "sensate reality vibrates", but I don't really understand what this means.)

 
"The most obvious explanation for vibration perception in meditation is that people are directly sensing their brainwaves and central nervous system (CNS) signals.... Direct sensation of CNS activity is a simple and straightforward explanation, because CNS oscillations are well-established scientific phenomena. "

This sounds a bit tautological to me.  I think you would need to also describe the actual mechanism for "sensing" brainwaves. How does this actually occur?

Alex, have you reached some of the progress of insight nanas? This is the most direct way of understanding vibrations as used in MCTB. Each mindstate tends to have it's own particular flavor of attention and framerate. 

A very comprehensive and comparative description of the nanas:
static.squarespace.com/static/5037f52d84ae1e87f694cfda/t/5055922624acbaa64592c1c3/1347785254496/







 

Shargrol,

To clarify, I feel nerves in the body twitching, vibrating, and tensing up, and I feel the brain twitching, vibrating, and tensing up in sync.  I'm inferring that I'm sensing brainwave and CNS signaling activity, similarly to how I infer that the sensation at the tip of the nostrils is really the breath.  Furthermore, some of the brainwave sensations I feel correspond in a consistent way with what I observe in EEG recordings.  Is any of this tautological?

Thanks for the table you provided of the ñanas; this is a useful resource.  I'll keep my response focused on the "vibratory quality" descriptions.  These are confusing to me for a few reasons:

1. I tend to think of vibrations as mathematical waveforms, which have well-defined attributes like phase, frequency and amplitude.  So many of the adjectives here don't make sense to me: what's a "crude", "chaotic", or "edgy" wave?  What's an example of a vibration that "cycles with breath"?  I can't get a clear picture in my mind.
2. It's also not clear whether the vibrations describe the sensory phenomena themselves (manifested as lights, sounds, etc.) or the rate of sensory processing.  For example, does "10 Hz" mean that I'm experiencing 10 Hz phenomena, or that I'm processing sensory phenomena at 10 Hz (regardless of their frequency)?
3. In whatever interpretation, the specific details here just don't match up very well with my own experience.  In terms of vibrations, I feel a lot of infraslow (less that 1 Hz) activity that isn't acknowledged here at all.  The energy profiles of my practice don't align in any obvious way with what I see here.

Hi Alex. You are putting too much thought into this. You are not feeling your nerves vibrating or your brain twitching. You are only experiencing the sensations of twitching, vibrating, tensing. The thought that it is your brain or nerves doing the twitching is just a thought, a memory of learned knowledge. Do not add any more to the sensations. Vibrations are only vibrations, and you are adding the thought they are mathmatical waveforms. Which is just a thought, which is also just an experience. Vibrations happen, they can feel slow, or fast. No one here will be able to tell you the reasons for this. I experience vibrations in a constantly changing flowing way and they can be different moment to moment. Why do they change, why do they sometimes disappear altogether? There is no part of me that really cares, they are just vibration.

Robert, please keep the original question in mind.  This is a discussion about whether there's science explaining a meditative sensory experience.  I argue that there is a simple scientific explanation, and discuss my own experiments and a published book by a scientist to support my point of view.  If you're not interested in science, that's fine, but then you shouldn't participate in scientific conversations.

Nothing ventured, nothing gained.

I say Alex should have it this (not that we can stop him). Who knows what might come of a rational investigation? I'll follow along Alex, assuming you keep posting here about what you find.

On the other hand, we can't tell others who disagree with us to leave the conversation.

From a completely factual/scientific perspective... do you feel nerves? do you feel the brain?  (Still seems tautological.)

I'd be very interested in hearing what people think about this question.

I don't have any comments regarding scientific explanations for vibrations, but below is my intuitive, experiential understanding of the descriptions used in MCTB2.

I understand "vibration" not as a mathematical term, but as a metaphorical description of sensations being here - gone - here - gone - here - gone, flickering in and out rapidly enough that it can be compared to the felt sense of, say, the vibration of a running motor ("VRRRRRRR").

As to how some vibrations can be perceived as edgy, chaotic, etc - I've been reading that as describing not the fact of vibration itself, but rather the surrounding (or embedded) sensations that are not yet vibrating, including a non-vibratory judgement of the vibrations as edgy, chaotic, etc.

This seems especially evident with descriptions like "chunky" - it suggests to me something like a big 1-2Hz "vibration" felt more as a rhythmic body pulse, thud-thud-thud. It's kind of unpleasant because it reminds me of heart palpitations, and each "thud" comes on in quite a dramatic and abrupt manner, and there are smaller vibrations that feel like they're running all over my body in a rather random and annoying way. But it's possible for this stuff to break down into smaller vibrations and have the unpleasantness break down along with it.

"Cycles with the breath", I see this as a felt sense of one type of vibrations synchronising with another. Eg sometimes, when I meditate with eyes open, the entire visual field can warp in a way that looks like it's expanding and contracting at 0.3-1Hz, or otherwise "wobbling", as if looking at a flag that is gently fluttering in the breeze, slightly distorting the image on the flag as it flutters. Sometimes this warping motion appears to synchronize with my in/out-breath (eg expand at each breath), or whatever I'm using as my object of concentration. Sometimes the micro-vibrations (>10Hz) that make up the slower "warping" vibrations also seem to change quality in a way that is synchronised with my breath. Or if I'm listening to music, the vibrations in my body can be felt to "bop along" with the music, responding to the beat, changes in rhythm or intensity, etc.

Again, I acknowledge this is a very fluffy description, written by a liberal arts graduate used to describing everything in metaphorical terms

As for question 3 about infraslow vibrations (<1Hz) - I'd suggest that each vibration (if observed closely enough) will contain faster sub-vibrations. The mental picture I get is that of Shinzen Young's 10 stage guide - see pp40-45 of https://www.shinzen.org/wp-content/uploads/2016/08/WhatIsMindfulness_SY_Public_ver1.5.pdf​​​​​​​

With all that said... I share your confusion about the idea that the frequency of vibrations can be diagnostic of PoI stage. Perhaps it's just because I'm not sufficiently familiar with the felt sense of frequencies to pinpoint how rapidly my vibrations are vibrating (like, I don't really know what 15Hz should feel like compared to 20Hz), or perhaps I'm not very good at clocking what insight stage I'm in. But it seems to me that I can feel different frequencies of vibrations at each insight stage, just depending on how I tune attention in the moment.
​​​​​​​
(Or perhaps, at risk of sounding tautological myself, the fact that attention is tuned to perceive a certain frequency of vibrations means that I have slipped into the associated insight stage...)

Shargrol,

Sure, is this controversial?  Why is feeling nerve or brain sensations more tautological than feeling the sensation of the breath, etc.?  I think it would help me to hear your own factual understanding of sensation to check that we're on the same page.

You have made a few references to your own experience but I am not sure under what conditions you experienced the things that you report. Shargrol asked about your experience with nanas, which seems to be a good question, because the OP is quoting from something described by someone who has been through a very specific set of practices (basically Mahasi noting) and talking about the resulting changes to perception. If you have not practiced in this way, or have practiced in another way, then it would not be surprising if your perception is different from that of someone who has, such as the person the OP is quoting.&nbsp;<br /><br />Although meditators may seek to understand how the mind works, what they ultimately see is how the mind works after performing the practices that make it possible to look at the mind in a new way. In a sense, they may be describing how a modified mind works. So these are fundamentally important measurement conditions, which must be carefully documented if we want to investigate in a scientific (or science-inspired) way.&nbsp;

I apologize Alex. I was not responding to your original post, but the post where you were clarifying things to Shargrol.  As far as what I wrote, take it or leave it. No matter.

Thanks, Robert.  I too apologize for my response.  I brought the issues of personal practice and experience into a conversation that should have remained a straightforward research question, as posed by the OP.  Given that I started discussing my own experiences here, your initial response makes sense.  That's on me.

Thanks, Martin.  I practice Goenka vipassana, not Mahasi noting.  You can find some details about my practice history in my [practice log].

Are "vibrations in sensory perceptions" a feature of your own practice?  Are you able to share details of them?  How do they relate to the insight ñanas, and the "vibratory quality" descriptors of MCTB (if relevant)?

Kailin,

Thanks for taking the time to share your perspective.  I'm by no means a science snob (I was a musician before pursuing math and stats), and I appreciate the power of metaphor as a tool for describing experience.  (The Buddha was a master of metaphor!)  Are the "vibratory qualities" literal or metaphorical?  This is a worthwhile question to add to those above.

Shinzen Young is an interesting teacher to invoke here, because he likes using science metaphors, but rarely ever discusses actual science.  On p. 41 of "What Is Mindfulness", or example, he uses Fourier analysis as a metaphor for sensory events, but I have never seen him use Fourier analysis in the context of brainwave signal decompositions, which is what you're likely to see in a neuroscience paper.

I have more to say, but I'm also interested in hearing more responses first, so I'll hold off for a while.

 
Thanks for mentioning your log. Seems to be mostly theoretical/framework-building so I can't really use it to guess where you are now, but based on what you said about your first 10 retreat, it sounds like you passed the stage of the knowledge of arising and passing away, which is where people generally gain the ability to notice things happening in the mind fast enough to appear as vibrations. So it is possible that your perception has been impacted by this knowledge. 

By the way, I'm reading Birth of Insight, which Similing Stone so thoughtfully reviewed here, and I notice the Goenkaji often spoke in terms of vibrations, so it is possibly a way of seeing that is likely to arise from that practice. 

Some years ago I devoted myself to Mahasi style noting/noticing and found that, when I was working at about 8 Hz, I saw lots of things as either vibrations or particles (particle/wave :-) ). I also found that low-frequency LEDs cause strobing for me. My guess is that the practice induced changes in the sampling rate or the smoothing mechanism that my mind was using. Years later, that change has been reversed and I no longer get strobing with LEDs or perceive things as vibrations. My current perception actually has a spacious, continuous feel to it, in which discrete entities (including particles) and reliably repetitive patterns, such as vibrations, are unlikely to occur. 

My takeaway is that vibrations are a way of seeing (for reference, Seeing That Frees, by Rob Burbea) that have a shifting/modifiable/trainable relationship with various underlying neurological constructs, which is to say they are probably highly dependent on conditions, rather than fundamental. 
 

Hey Alex,
I'll throw in my 3 cents here.  So when you say 'vibrations', this can mean a lot of different things. 

There's 2 different things that this could be referring to when I think of vibrations:
1, the static energy of experience - the 'flickering' of sensations- in the visual sense this can appear as kind of analog snow, in the hearing sense 'crickets', in the felt sense, 'tingling'.  My theory is that this is just a sensitive mind's observation of the rising and falling of each individual sensation. It's the combination of these millions of individual risings and fallings of sensations that makes up the 'static' field of experience. 

What does this mean at the biological level?  I'm not sure, I'm not a biologist or neurologist.  I think you could ask the question, "what is actually happening when you stub your toe on a rock?" and it would be a similar answer.  When you feel a tingle or when you hear a buzz in your ear, it's a sensory signal that's being received and processed by your brain and your nervous system.  Does that mean you are 'seeing your brainwaves'?  Or is your brain just doing its thing and interpreting a stimulus?

2, There's another thing I think of when you say 'vibrations' which is sort of like the flashing / strobing effect that happens when doing vipassana like for exemple in the Mahasi style noting.  In this case, the Hz or the frequency of these vibrations can vary - from person to person, and within the same person's experience.  I think this is just a reflection of the mind's ability to process and register individual frames of experience, and that frequency can vary.  So that would indicate to me that it's not something that's tied to some 'external' biological clock, like humans have some sort of internal frame rate that we all operate on or something, no I don't think so.  

3,  When you say ‘tension’ - in my mind this is completely different than ‘vibrations’.  Tension is like a nervous/muscular release or clenching of some sort.  In my experience it's tied to mental clinging, anxiety, and sometimes it feels released when you tense or twitch a muscle, for example.  Very different concept than 'vibrations' in my mind.

​​​​​​​EDIT:
“How do they relate to the insight ñanas”
Strobing specifically is a hallmark of 2nd vipassana jhana. Nanas are knowledges, I think strobing would correlate most closely to the knowledge of rise and fall, or the A&P as referred to here and in MCTB.

Martin,

You mentioned strobing caused by low-frquency LEDs.  I noticed something similar near the end of my first retreat: I could see a certain florescent light flickering (I’d guess at around 15 Hz), when previously I'd seen it as continous light.  This is one of several changes of visual perception that occured on that retreat.  I agree with your general conclusion about the trainability of perception.

​​​​​​​I’m still not sure what you mean when you say that you "saw lots of things as either vibrations or particles".  Is the visual effect limited to what you describe with the LEDs?  Or did straight lines appeared wavy sometimes?  Or did you see a layer of visual snow?  Or were you able to see matter at the quantum scale, where you could observe the wave-particle duality directly?

I was joking about the wave-particle duality thing :-)

Particularly during sitting, sensory input was granular, with visual things (see-in) appearing as if made of discontinuous particles, sounds (hear-out) hitting as waves (pulses) such as happens with deep bass notes in ordinary life, and tactile senses buzzy, like the flesh was vibrating. 

It may be worth noting that, in the same general time period, I also had what could be considered hallucinations (or siddhis), such as being able to see through closed eyelids. 

My takeaway is that the way the mind processes sensory input is variable and depends on the way we get used to looking. 

Thank you, J W!  Brief responses to each of your three points:

1. Brainwave processing vs. seeing brainwaves: I mostly agree with your first point.  I want to be careful, however, to distinguish between "sensory signals being processed by your brain" and "seeing your brainwaves".  The former is a general phenomenon.  By the latter, I mean, specifically, seeing the brainwave electromagnetic vibrations in the phosphenes.  I recently wrote about this phenomenon in the DhO Seeing vibrations thread.

2. Strobing/flashing: Martin also wrote about visual strobing, and I’ve experienced it practicing Goenka vipassana.  I associate the effect with other sensory threshold changes: for example, since starting intensive vipassana practice, I can also hear harmonics more clearly, smell and taste more deeply, etc.  Questions: when you are "processing frames of experience", do you ever experience vibrations in any non-visual sense (hearing, etc.)?  If so, can you describe the effects?

3. Tension and vibration: yes, these are distinct, but tension can vibrate!  A fluttering eyelid is vibrating tension; so is a heartbeat.  More subtly, so is the nervous system activity in the body, and it can be felt as such with practice.

Martin, I assumed you were joking about wave-particle duality, but it never hurts to check!  (In my least favorite part of the vipassana course evening discourses, Goenkaji equates kalapas with subatomic particles.  I hope no one takes that analysis too seriously.)

Interesting post — thanks for keeping it alive with your experiments. Another aspect related to your question is this: when I move my attention from one part of the body to another ("part to part"), I notice that the sensation (whether vibration or something else) seems to become “activated” in the spot where attention lands. Do you know if there’s any neurophysiological explanation for this, or any research/books about it?

At GuruViking sometimes he talks about science. By the way, perhaps not everyone knows that he has recently (10th October) retired from active teaching in order to focus on research in the lab with Dr. Sanguinetti.

I wanted to share links to a couple other DhO threads that are relevant here:

So, what are vibrations? describes the experience of body sensations (including vibrations) during Goenka vipassana.  The OP seems interested in fitting his experience of vibrations into the MCTB framework; Nikolai advises him not to worry too much about it.  Based on the discussion in the current thread, Nikolai's advice seems sound.

How to concentrate in slow brainwaves includes links to research on brainwave band power changes during sleep and vipassana meditation.

Polymix P, thanks for sharing.  Shinzen Young's retirement from teaching is news to me.  Regardless of my distaste for Shinzen's science metaphors, I've learned a lot from him in other respects, and I wish him happiness in his work with Dr. Sanguinetti.

1) When you say 'seeing the brainwave electromagnetic vibrations in the phosphenes', this is another way of saying, 'seeing flashing/strobing lights' yes?  So help me understand... why do you think this is electromagnetic and where does the concept of 'brainwaves' enter the picture here?    

So I take it from your response that you are defining 'vibrations' as 'strobing'?

2) I don't typically experience 'strobing' in the hearing sense (though I do hear crickets), I think if you were to apply the sine wave metaphor to hearing, I would think of like a pulsing (think binaural beats), where you are hearing the peaks and valleys of each wave in the same way you are seeing the peak and valley of each wave in the visual sense.  Same thing with feeling sense, each 'pinprick' is a feeling of each wave rising and falling.

3) Can you give me an example of a perceived phenomenon that does not 'vibrate'?

Hi Polymix P,
​​​​​​​

​​​​​​​Good question; I've noticed this too, but haven't looked into research on it. It may be related to sensory gating.

All this talk about vibrations and nary a mention of impermanence  

I think this is quite literally what 'attention' is.  You are noticing sensations in the spot where your attention lands because that is where your attention is focused.  I'm sure there is plenty of literature and research on how attention works on a neurological level.  Not sure that you will find it here... but interesting nonetheless.

Page 21!

J W,


Yes, flashing lights.  The lights often flash at brainwave frequencies I can see in the EEG spectrum (in particular, there's subtle flashing at 10 Hz), and that I can feel inside my head, where the brain is.  Brainwaves are electromagnetic oscillations, and there's scientific evidence that phosphenes can be caused by electrical stimulation of the brain or by magnetic field changes (see Wikipedia).  So, I conclude that I'm seeing the brainwave electromagnetic vibrations in the phosphenes.  Do you draw a different conclusion?


It would be helpful to know the frequencies of the sense phenomena you're describing.  The frequencies of binaural beats are often low enough (say, 30 Hz and lower) to be heard as discrete pulses.  Do you hear discrete pulses for higher-frequency sounds as well, say 100 Hz and above?  If so, is it possible that you're actually hearing lower-frequency combination tones?  For the "pinprick" felt sensation, what specific frequencies are you experiencing?


Sure.  The felt sensation of pressure in the legs while sitting is static and doesn't vibrate.  The heard sensation of a 440 Hz pure tone is likewise static and doesn't vibrate (even though the air itself is vibrating!).  When I'm driving, the visual scene is changing, but not vibrating (there's no visual oscillation).

To me this sounds like an interesting theory, especially regarding the visual sense specifically, as when I see 'strobing' it usually occurs somewhere between 1-8 times a second (1-8Hz, which is as you say, within the EEG range), but it's not proof of anything.  

The general 'flickering' appears much faster than 1-8 times a second.  It looks similar to static on a TV.

I prefer to not draw conclusions without evidence.

As a counter point, and also in response to point 2: 
The 'static' in the hearing sense (crickets) is sometimes compared to tinnitus.  I would describe it as a combination of many different overlapping frequencies (similar to white noise) with most of those frequencies being much higher than the ones associated with brainwave activity (keep in mind I'm just reading about this stuff for the first time on Wikipedia so perhaps I'm wrong).

The fastest brainwaves are Gamma waves, with a range of 31-100Hz, according to this link:
https://www.neeuro.com/blog/understanding-electroencephalogram-eeg-for-better-brain-health

Tinnitus typically occurs between the 5k-10kHz range, and what I hear I would definitely describe as being in this range.


I would disagree.  Sitting here now on my couch, I feel the pressure of the couch, and that pressure has a tingling, vibrational aspect to it that is just like the tingling described earlier as part of the static energy field. Same thing with the 440hz tone and driving.  There's still the 'static' vibratory quality in both the hearing and the seeing.  In other words, it doesn't matter what is happening in any of the sense doors, the vibrational static element is there.  (for me, at least).  Now, I will say that sometimes that vibrational quality is less apparent if it is not being focused on.  But there, nonetheless.

This is my experience at least.

EDIT: You asked for my conclusion, and while I'd like to reiterate that I do not know, I'm happy to give you an alternative theory.  When you see 'strobing' - (and when I say strobing, I think of that as distinct from the 'general static'- Both vibrational, but distinct phenomena, if you will) -

what you are 'seeing' is the speed of attention.  The rate at which the mental processes that make up what we call 'attention' register one individual frame. Sort of like the CPU - how fast can the mind can process a single thread. Whether this correlates to 'brainwaves', I don't know, but I still don't see any reason to think that it does.  It seems to be variable, and can speed up and slow down. 

I think I already described what I think 'it' is -the rising and falling of individual sensations- whether in the static field (broad) or the strobing sense (narrow, zoomed in).
 

If you can't tell, I'm pretty interested in this
Thanks for the conversation.

I was thinking about your point about seeing colors or strobing being caused by electromagnetic sources. Well you got me curious.  So I asked Google what role electricity plays in the senses and their cortex:



all human senses require electricity
, as they work by converting stimuli (like light, sound, or chemicals) into electrical signals that travel along nerves to the brain. This process, known as sensory transduction, relies on the flow of ions across nerve cell membranes to generate electrical impulses, or action potentials, that the brain then interprets. 



Q: Are brain waves related to sensory trnasduction?

A: 
Brain waves are not directly related to sensory transduction
; rather, sensory transduction is the initial step that creates the electrical signals that are then integrated and processed to form brain waves. Sensory transduction is the conversion of physical stimuli (like light or sound) into electrical signals by specialized sensory neurons, which then travel to the brain. Brain waves, a large-scale pattern of electrical activity, emerge as these and other neural signals are processed in networks of neurons throughout the brain. 


FWIW I think that electricity probably plays a role in pretty much everything that we experience since it's how the body communicates with the brain according to this very basic explanation. Electrical signals will also have a frequency of their own.

So what does this all say about your theory? I don't know. I wouldn't say it proves it though.

How would you propose to measure and prove that hypothesis? If you could find a way to prove a correlation between brainwaves and speed of attention, I'd say you might be onto something.

Have you looked into the EPRC? this seems like something they might have some literature about or be otherwise knowledgeable.  I know that there have been some recent EEG studies on meditators, for example:

https://meditation.mgh.harvard.edu/files/Laukkonen_23_ProgressInBrainResearch.pdf
https://pmc.ncbi.nlm.nih.gov/articles/PMC4684838/

There's dozens of studies from the looks of it.  Google: eeg research on meditators

I think it's been proven that meditation does have an effect on brainwave output.  

I have less invested in this conversation than JW, but I'll add that It's always good to ask how some idea is falsifiable, too. What would it take to disprove that the experiences of meditation vibrations are the direct experience of brainwaves?

J W, 

Thanks for your interest.  If you have the money and the desire to learn more, I recommend buying a Muse (a Muse 2 is sufficient).  Then you can do some experiments on your own to explore vibrational awareness.  Incorporate EEG readings into your own practice; see if the frequency graphs align in any way with your own experience.  Kaio's book is an instructive model.

At this stage, I'm just collecting data informally and sharing some experiences.  I'm not too concerned about designing experiments to convince scientists that I'm correct.  It's more important to me to have conversations with other meditators to get their feedback.  Eventually I will share some EEG recordings here, but it will take time, because I work slowly.

Shargrol,

I'm open to alternative interpretations, as long as they're supported by some evidence.  It could be that meditators are picking up vibrations from an external source (for example, signals from nearby electronics, or the Schumann resonance).  Maybe, as J W suggests, the vibrations are an artifact of "attentional speed", or some other internal process that's not directly related to brainwaves.  At the moment, I find my own explanation more convincing than any of the others, but I've certainly been wrong before.

I'm curious about how the conclusions are useful to you. If, for example, the vibrations noticed by meditators were brainwaves, would that impact your practice or steer your investigation in some way?

Also, as a fun exercise, you might want to investigate the felt sense of labeling sensations as brainwaves, compared to, for example, labeling them as unknown. If you try that, do you see a difference in either the sensations themselves or the overall tone of the mind?

Likewise Alex!
So, EEG measures brainwave activity/output.  How would it be used to measure the composition of internal phenomena (strobing, etc)?

Martin,


It has certainly steered my own investigation.  Once I guessed that I was sensing brainwaves, I found Paul Dennison's work.  Dennison discusses infraslow waves in the range of 0.01 -- 1 Hz, relating them to the experience of jhana in samatha practice (see some of his notes here).  This hinted to me that I should expect to feel something in that frequency range too, if I poked around enough.  So, I made some binaural beat recordings to get a feel for those very slow vibrations.  I practiced consistently with the recordings while maintaining my standard Goenka body scan practice.  Sure enough, after a couple months, very gradually, I started to tune into the infraslow waves that Dennison describes.  The refinement of infraslow sensation continues in my practice today.

(I wrote up a short memo on infraslow waves a few months ago here.  The main idea stands, but I would present the evidence differently now, because my felt experience of the infraslow waves has evolved.  Also, there are better ways to visualize the spectra.)


​​​​​​​In the Goenka method, one is just supposed to notice the sensation, notice that it's impermanent (there you go, Chris M), and move on.  This is how I try to practice.  Of course, I notice things while practicing, but I try not to dwell on them until after the practice session is complete.  (I have spent a lot of time chewing on thoughts, so switching out of an analytic thinking mode to an intuitive sensing mode is difficult, but very important.)  The results of practice are better that way: sensations are more transparent, body tension dissipates, and the overall effect is spacious and flowing.

J W,

I don't know how one measures strobing directly.  To study the brain's sensory processing speed, I'm aware of the attentional blink test, which Daniel discusses in this interview (around 29:40; in short, Daniel claims to have aced the test, and he says that there was a conference presentation about his performance, but I can't find it online).  Richard Davidson has also written about meditation's ability to shorten the attentional blink in his book Altered Traits.

So how would the EEG be useful - what exactly are you measuring in this scenario?

Watching objects arise and pass through their "atomic parts" quickly certainly can reveal insights into how our experiences come about. But... does a person need to have ultra-high attentional speed to have the insights that lead to their awakening?

J W,

The EEG is always going to measure brainwave activity.  It's not necessary to have the EEG for the attentional blink test, or for various other cognitive tests.

Another Goenka student here. We have been trained to work with vibrations. Goenka encourages to look for all types of sensations and does not pick out vibrations. But after couple days of focusing on sensations on your upper lip (tickled by breath) most will start noticing vibrations. It does not require A&P or any specific jhanas. Once you master it, you start sweeping the body - moving the vibration wave up and down, and checking for blank spots. Once you know what to look for, it's easy to get the feeling momentarily, at least in fingers and toes. As I type, I shift my attention to any of them and the feeling is there. 

Some observations.

Why fingers and toes? Possibly because they are densily packed with nerves. 

Vibrations are much blunter (or absent for a beginner) in dark night stages.

During the retreat, I suffered with insomnia. I was advised to effortlessly watch sensations in my finger tips while resting in bed. The first nigth I felt the frequency (the background tinnitus type noise in my head) go down a step before falling asleep. The next nigth I experienced frequencies going down in a few smaller steps (like I was more tunned in). I am inclined to believe that this one was my brain frequency.

Goenka gave one example where some practicioner was tunned in so much that he counted his body atom vibration cycles, and later checked with scientists that the figure was correct. Goenka was a good story teller.

Anyone considered if we can feel our blood flow through our capillaries? 

Thank you, pieva!

I appreciate the observation about vibrations in the fingers and toes, which are easy to feel with minimal effort.  You are likely correct about nerve density.  The recommendation to focus on fingertip sensations while falling asleep is nice: I hadn't heard that before.

I can feel the blood pulsing in various parts of my body, including the fingertips.  This sensation is different from the vibrations, which have a higher frequency.  I don't associate any sensation with the continuous flow of the blood.

In terms of mapping, I agree that the sensation of vibrations is not necessarily indicative of the A&P or of jhanas.  The vibrations do seem to indicate that the meditator has become more sensitized to subtle felt sensations, thanks to Goenka-style anapana practice.


Can you describe what you mean by "blunt" vibrations?


This is interesting—I've experienced something similar, I think.  While meditating, I will sometimes hear a "ping" that's lower by an octave or two than my usual background "crickets".  The ping comes with a weird collection of sensations and psychological effects.  The general feeling is of something in the brain switching off; this manifests as mental quiet, a feeling of spaciousness in the temple, and retroactive awareness of a scrambled white-noise-type sound.  If anyone else has experienced something like this, maybe we can discuss it on a separate thread.
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He was a good storyteller.  I believe that practitioner in the story is the Buddha himself, counting kalapa cycles.

A delved a bit deeper into this last night. That's how I understand the vibrations.

In essence, everything in this world is vibrations. According to quantum physics, even the 'solid' particles like electrons, protons and neutrons are not solid but exist as probability clouds and waves.

When we feel vibrations, it is an amplified feeling of whatever feeling we have in our body. We feel that our fingers are warm. Vibrations could be the same feeling of warmth but amplified by our brain. Whatever mechanism our body uses to transmit this feeling of inner warmth, is also the mechanism that we perceive vibrations. What makes our body warm? Flowing blood, also muscle activity. There must be a lot of movement on microscopic scale.

It was only during my first retreat that I went through a full-blown dark night. Before A&P vibrations on my face felt like I was a purring cat, but I couldn't get the same feeling later. Much more of my body was blank, compared to the sensations earlier. I wish I knew about the maps back then as I felt a failure. 

When other meditators speak about different vibrational frequencies related to different states, I guess it could be something to do with the amplification, and this might be a product of brainvawe frequency.