First, I think it appears that memory is an original faculty given us by the Author of our being, of which we can give no account, but that we are so made.(from Essays on the Intellectual Powers of Man, 1785 edn. available on Google Books - ereaders search for Essay III. Then to Chap.II. or pg.320 on Sony ereader)I will have to append a note on efficient search on ereaders that is universally valid.
The knowledge which I have of things past by my memory seems to me as unaccountable as an immediate knowledge would be of things to come; and I can give no reason why I should have the one and not the other, but that such is the will of my Maker. I find in my mind a distinct conception and a firm belief of a series of past events: but how this is produced I know not. I call it memory, but that is only giving a name to it; it is not an account of its cause. I believe most firmly what I distinctly remember; but I can give no reason for this belief. It is the inspiration of the almighty that gives me this understanding.
As Bergson has pointed out in an essay which I wrote about recently
the idea of the connection between brain and memory has been well noted for a long time and is not the trump card magicked from the sleeve of modern science. Thomas Reid finds the outline of the theory in a a commentary by Alcinous on the doctrines of Plato.
When the form or type of things is imprinted on the mind by the organs of the senses, and so imprinted "as not to be deleted by time, but preserved firm and lasting, its "preservation is called memory".
Upon this principle Aristotle imputes the shortness of memory in children to this cause, that their brain is too moist and soft to retain impressions made upon it: And the defect of memory CHAP. vii. in old men he imputes, on the contrary, to the hardness and rigidity of the brain, which hinders its receiving any durable impression.
Reid also admits the lesion evidence but rejects the idea that this demonstrates anything about the nature of consciousness because there is no resemblance between nueronal events and the experience. I take this to mean that simply stating that one is the other or causes the other is to use the words 'cause' and 'identity' in ways which we have no experience of, that do not relate to our ordinary uses of these words. He writes:
It is probable that in perception some impression is made upon the brain as well as upon the organ and nerves, because all the nerves terminate in the brain, and because disorders and hurts of the brain are found to affect our powers of perception when the external organ and nerve are found; but we are totally ignorant of the nature this impression upon the brain: It can have not resemblance to the object perceived, nor does it in any degree account for that sensation and perception which are consequent upon it.
Excuse these long citations but it is probably necessary to emphasise the fact that the knowledge which modern neuroscience demonstrates through brain imaging does not evade the 'hard question' which was clear to the savants of the late 18th. century however approximate their physical findings were. Reid's close examination of the absurdities involved in the 'impression' theories of Locke and Hume bring to mind similar analyses in Matter and Memory by Bergson. I found Epistemological Problems of Memory
the Stanford entry on the Epistemological Problems of Memory to be very helpful on this.
Finally to demonstrate how far common sense can take you from the high road of scientism: (from E.I.P. pg.322)
Our Maker has provided other means for giving us the knowledge of these things; means which perfectly answer their end, and produce the effect intended by them. But in what manner they do this, is, I fear, beyond our skill to explain. We know our own thoughts, and the operations of our minds, by a power which we call consciousness: But this is only giving a name to this part of our frame. It does not explain its fabric, nor how it produces in us an irresistible conviction of its informations. We perceive material objects and their sensible qualities by our senses; but how they give us this information, and how they produce our belief in it, we know not. We know many past events by memory; but how it gives this information, I believe, is inexplicable.