I recorded my brain activity during a HEG neurofeedback session. More specifically, that means I recorded changes in infra-red heat radiation coming from my forehead. This form of biofeedback is used to train “executive function”, which is the job of the prefrontal cortex (the part of the brain behind the forehead). In this session I interspersed periods of intense focus with watching TV. You can see the results in the graph below.The software (which I developed myself) allows me to train in bursts, in this case three minutes long, which are shown in the graph as the yellow bands. You can see a clear difference in the signal, between training and watching TV.
What I’m doing in the training periods is a kind of mindfulness (meditation) practice. I don’t have a specific object of focus, rather my intent is to be intensely and vividly aware, or self-aware, in the present moment. It’s sometimes known as “open presence” meditation or “pure awareness” meditation.
The graph shows that my brain activates consistently during the periods of practice, and then deactivates during the television-watching rests. It must be admitted that I’m being more “effort-ful” than I would in a normal meditation. You can see how, by the end of the third, I’m beginning to tire, and the trace becomes more wobbly.
This brings out an important point about this kind of biofeedback. It would be far too simplistic to say that up is good, and down is bad, or even that activation is good and de-activation is bad. Practically speaking, the key to successful living is flexibility of state, which translates as flexibility of brain (and body) state. If I’m at the office listening to a presentation of complex ideas for which I need sharp focus, well that’s one brain state – and then when I come home and relax that’s another. And when I go to bed and fall asleep that’s another brain state again. I need to be able to easily and flexibly access them all. If my brain loses flexibility, then it might mean I can’t get to sleep at night.
Coming back to HEG neurofeedback, I find it useful to be able to train in bursts. This is in part because I don’t think the brain is particularly designed for long uninterrupted periods of intense focus, but also because it’s useful to see the flexibility. And just because the brain temperature comes back down again, doesn’t mean we lose the benefit.
There is perhaps a parallel with interval training. Recent research suggests that short periods (just a few minutes) of very intense physical activity can lead to long-lasting changes – to insulin sensitivity for example. During the exercise the heart rate goes up, but then comes back down again – it would be worrying if it didn’t. In fact the fitter you are, the quicker it will return to normal – flexibility again.
Just as in physical training we’re not aiming for a permanently high heart rate, so with HEG neurofeedback training we’re not aiming for a permanently hot brain. It’s just that regular exercise improves responsiveness, or adaptability, or flexibility.