Mind and Brain
There are generally two approaches to understanding the relationship between the mind and the brain. By mind we mean the subjective side of things, the full range of lived experience, both conscious and unconscious, including such things as thought, cognition, memory, desire, emotional states, and even perhaps the sense of transcendence.
By brain we refer to the objective side, the physical stuff between our ears, with its complex architecture of inter-related neurons and the electro-chemical processes activating and connecting them.
One approach regards the two as basically identical. In this view all subjective experience not only depends upon but also consists of brain activity, and when we have fully mapped out the functions of the brain we will have explained the mind.
The other approach considers the mind to be much more than the brain, extending far beyond the merely physical in both scope and capability in ways that the current scientific models either have not yet conceived or a just beginning to glimpse.
In this view there are of course parallels between brain activity and subjective states, but the one does not entirely explain the other. Traditionally (both east and west) this non-physical perspective on consciousness that are outside the matrix of physical cause and effect.
This view has been steadily retreating before the advances of neuroscience, but recent iterations of it are looking to the new physics for ways of articulating a deeper and more fundamental relationship between mind and matter than formerly imagined.
In Buddhist terms the question comes down to whether all consciousness is conditioned, as the consciousness of the grasping aggregates surely is, or whether consciousness might also be conceived in larger, even unconditioned, terms.
Such is the case in some of the later forms of Buddhism, like the Mahayana and Vajrayana, but there are many in the Theravada who see it this ways as well. The issue turns on how we construe the word “unconditioned” (asankkhata), which is regularly employed as a synonym for nibbana.
If everything is conditioned and nibbana is the one state that is unconditioned, then surely awakening consists of at least glimpsing if not deeply experiencing a form of consciousness well beyond conditioned phenomena and thus beyond the mere brain.
On the other hand, the term “unconditioned” is most plainly defined only as the absence of greed, hatred, and delusion (as in the Asankhata Samyutta, 343), consciousness is specifically declared to be conditioned (Majjhima 38) and nowhere, at least in the Pali texts, do we find the (oxymoronic) phrase “unconditioned consciousness.”
Either some are making too much of consciousness, or others are making too little of it. As I understand the early teachings, the Buddha was trying to steer us to a middle way of approaching this issue, a way between what he called eternalism and annihilationism.
It is tempting, both in ancient and contemporary tradition, to essentilize consciousness or ascribe to it a status well beyond “that which appears” in experience when a sense object or a mental object is cognized by means of its corresponding organ.