Most of us are pretty confident that we are not hallucinating. We take it for granted that imagination is quite different from our experience of reality through perception. But recent research in neuroscience has questioned this relationship and made it more puzzling. Brain activity in the visual and sensory cortex can be as strong during dreaming and imagined events as when we perceive reality. Furthermore, blood flow between the sensory and visual cortex can also show similar patterns of activity in imagination and perception. Some leading neuroscientists now go as far as to argue our perception of reality is a “controlled hallucination”, breaking the traditional perception/reality divide and echoing the influential German philosopher Kant who maintained “imagination is a necessary ingredient of perception itself."
Has neuroscience uncovered a deep philosophical truth that what we take to be reality is in part a function of our own imagination? Might neuroscientists find a brain process by which we distinguish imagination and reality? Or is it a mistake to think neuroscience capable of answering fundamental questions about the nature of perception and reality in the first place?