Posture. It isn’t just for looking good. It seemingly affects your physiology too.
I was having real trouble with my muscle tension (EMG) in today’s brain biofeedback (or neurofeedback) session. It was reminiscent of the old days, during my original stint with this therapy. As a result, I wasn’t doing too well. My heart rate was up and my gamma brainwave/EMG ratio was up and down instead of improving with each screen. Although EMG does affect gamma wave readings, technically it shouldn’t affect how well I can actually produce the darn gamma brainwaves, or so that was my understanding.
Well, maybe it does
After another not-too-bad three minutes playing a game with my brain on the computer, the results were again not great, in fact down. I was rather peeved. My trainer had me do an extra session to try once more to increase it and so leave on a high note.
Suddenly I wondered if maybe my neck was turtling more than usual. I made an effort to stretch it up and back, much to its stiff displeasure. My EMG dropped like a stone. Who knew the effort of keeping my neck straight would reduce tension not increase it!
Turns out there’s a reflex identified by Sir Charles Sherrington in which if you contract the antagonist muscle, the muscle you’re stretching will relax (and stretch more). So by contracting the muscles at the back of my neck, the ones in the front relaxed and thus, I guess, decreased the EMG.
Even better, my heart rate dropped from 111 to 108. Finally.
Even better better, my gamma wave/EMG ratio rose and then finally got back up into the 0.90s. That extra feedback session and change in posture made a diff. I did leave on a high note after all. I also was rather tired and hungry.
That was the other interesting thing. I ate an entire Simply Bar just before my session so that my brain had food to suck up while working hard. About in the middle of the first feedback screen — a roller coaster — hunger hit me with a vengeance. Holy cow! The CR-Pregabalin had increased my appetite in a way I was barely aware of; this was instant-on, demanding, feed-me-now appetite.
I fed it a nuts-and-fruit snack bar when I left. I fed it more when I got home and felt better for it.
The feedback screens I used this week were roller coaster (a short one-minute one then after adjusting speed, full three minutes), bowling, plane, sailboats, and HRV (heart rate variability with eyes closed and open) to warm up and cool down. The results (rounded to decimal places by me, which is a bit imprecise but will do for here):
| Date | Baseline | HRV EC | HRV | Fdbk 1 | Fdbk 2 | Fdbk 3 | Fdbk 4 | Fdbk 5 | HRV EC |
| 27 Jun | 0.83 | 0.88 | 0.90 | 0.90 | 0.91 | ||||
| 4 Jul | 0.85 | 0.90 | 0.91 | 0.94 | 0.898 | 0.90 | 0.84 | ||
| 10 Jul | 0.85 | 0.92 | 0.89 | 0.86 | 0.84 | 0.86 | 0.83 | 0.86 | 0.90 |
