Hi all,

I have recently started jhāna meditation following the instructions in Leigh Brasington's Right Concentration and, so far, have made it to the second jhāna.  In describing the first jhāna, Right Concentration notes that many people experience an increase in body temperature.

This got me curious to see whether my own meditation has measurable physical effects.  I don't have a great way to measure my body temperature during meditation, but I do have an Apple Watch that tracks my heart rate.

Thus, my question: Should I expect any change in heart rate based on any meditative states?  I'm especially interested in  heart rate in the jhānas, but I'd be interested in any biometric data typically associated with any meditative state (including "normal" meditation that doesn't produce an altered state of consciousness),

I initially expected to see a notable heart rate drop during access concentration, followed by a significant increase in the first jhāna, and then a drop in the second jhāna.  Instead, my heart rate was significantly above resting the entire time.  It jumped around a bit, but not in any way that seemed to be correlated with the stage of my meditation.  (After my meditation session, I checked my pulse in the same posture and it was about the same.  So the posture probably explains the elevated pulse compared to baseline.  I sit in the seiza posture, in case that's relevant.)

Given that I'm not seeing the pulse changes I expected, I see three possibilities:

• I'm wrong to expect any change in pulse
• My watch isn't accurate enough to detect a change of the magnitude I should see
• I'm not actually attaining the jhānas I think I am

Has anyone else measured their heart rate or other biometrics during meditation?

That's the book that got me started in this....you already achieved  2nd jhana.  may I ask how many hours a day you put in .please pm me.

Hi Daniel,

I tried out concentration practices and jhana using an Emotiv EEG headset. This converts brain activity to estimated emotions using proprietary alogirithms, so it is hard to know exactly what they mean.  However. I recall that when I increased piti the Emotiv metrics showed increase in either 'excitement' or 'stress' (I forget exactly which now). And indeed, first jhana in particular is quite energetic in my experience.  So I wouldn't expect a drop in heart rate in first or even second jhana. 

Good luck.

Malcolm
 

Thanks, that's very interesting.

What was your experience with the EEG headset like overall?  Is that something you'd recomend?  I tried out the biofeedback sensors in Journey to Wild Divine(https://en.wikipedia.org/wiki/Journey_to_Wild_Divine) and didn't find it at all useful.  But that was well over a decade ago, and I imagine the technology may have improved dramatically.

Do you happen to remember whether you used the 5-channel version or the 14-channel one?  There's quite a significant price difference.

It was the fourteen channel version. It was good fun, and certainly enabled me to demonstrate that entering different light jhanas resulted in significant and sustained shifts to some of the measured 'emotions'. But I don't think it is of much use for training meditators, as I'm not aware of an account of what the target 'emotions' should be. Also, it is quite pernickety - getting good sensor contacts, going through the calibration, losing sensor contact in long sessions as the saline solution dries out - all these things make it hard to use. Luckily I don't have much hair, so that made it slightly easier.  

The calibration exercises did provide a good format in which to demonstrate sustained concentration. That was fun. So I would say yes it is useful to help to understand and test concentration, but no we don't know enough to use it to develop jhana. Or at least I don't know enough!

M. 

I recently bought a Cognionics Quick-20R dry/wet EEG headset (not yet available to view on the Cognionics website, as it is so new), a research-grade 20 contact rig. I have been and will be my own meditation runs at home and on retreat, as well as that of friends when on retreats early next year, and evaluating the data with some university-based researchers. I am also learning to look at the data myself on EEGLAB. I will also have an ECG lead for some of it, so, if I find anything related to heart rate, will somehow get that out there. I also have been thinking of buying a pulse oximeter, as clearly there is some hypoxia that can occur in some deep states, as I have noted before when I was in an emergency department with a kidney stone hooked to monitors and meditating.

Couple of questions out of curiosity, Daniel: How much did that gear run you? (The site doesn't have a price listed for the QUICK-20 which seems similar). Instead of measuring oxygen could you not hook up some kind of band around your torso to measure depth and frequency of breathing? Also, do you plan on opening up your data? See here etc

For OP:
A lot of people are interested in doing this, but as far as I can tell most or all of the consumer-grade EEG sets don't work well. For higher grade gear see Emotiv and OpenBCI.