Christian B:
it would be great to have a reliable explanatory framework for all the strange stuff that can happen in meditation. Only, as far as I can see, no such framework exists, and instead, the search for comprehensive explanations (of the kind you mention) regularly leads to a proliferation of perspectives, interpretations, theory, concepts and so on, as well as a proliferation of debates around these topics, identifcation with specific views, arguments, confrontation etc.
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Or do you believe there is a framework that can explain all the weird stuff that is talked about around here in a helpful way?
Yes, I believe we have a framework - that of a conventional scientific materialist worldview. In such a framework, weird stuff no longer is so weird.
Now the question of "useful" - at this stage its use might be quite limited pragmatically speaking, because linking science and spirituality is still in the early days. But if we are going to have a reliable overarching theory I don't see another game in town, and by rejecting it or being agnostic it feels like delaying the inevitable, and choosing to keep ourselves in the dark for short term benefits. So I can see some negative aspects, as you point out, about adopting a position and trying to work out what is going on in the brain has its limitations, and avoiding the endless go-nowhere arguments about metaphysics. But it seems ultimately short sighted, depending on what the longer terms goals of this community are.
I have harped on about related issues before:
http://dharmaoverground.org/web/guest/discussion/-/message_boards/message/4451315
Bruno Loff:
sawfoot, I happily agree that these vibrations are probably caused by neuronal activity of some kind, possibly together with changes in blood flow, oxygen distribution, etc, you name it.
Nonetheless, I still don't have any clue what these vibrations are, in that I don't know how to fit them with any of the various ways I have to think about meditation.
So thinking about what is happening in the brain is very good way to think about meditation, and that lack of a coherent account in the usual frameworks (which have been around a long time) highlights inadequacy in those frameworks. Right now the brain-based framework is still developing, and while not predominant in spiritual circles like the DhO, we are the point that we can say useful things about these phenomena.
So in my speculative opinion, I definitely think it is significant, though I can't really say why it isn't mentioned (much/at all?) in sutras etc...
My perspective would be that various sensory phenomena like flickering in the visual field, ringing in the ears, vibrations around the body ("kunadlini") etc... may be reflective of similar origins in types of meditation practice. These may include both concentration and insight practices, depending on how are done. As a "side effect", they reflect increases in power in certain frequencies of oscillations of neuronal populations - increases in neuronal excitability and synchrony - which can have short term (meditation state) and longer lasting temporary effects (off cushion stuff flickering while looking at the sky ). They may be linked to plasticity that can induce more lasting changes, and focusing on them could lead to a form of feedback loop which induces more widespread changes in neuronal synchrony and network configuration in your case - aka stream entry.