Abstract
It is widely accepted that consciousness or, in other words,
mental activity is in some way correlated to the behavior of the
brain or, in other words, material brain activity. Since quantum
theory is the most fundamental theory of matter that is currently
available, it is a legitimate question to ask whether quantum
theory can help us to understand consciousness. Several
approaches answering this question affirmatively, proposed in
recent decades, will be surveyed. It will be pointed out that
they make different epistemological assumptions, refer to
different neurophysiological levels of description, and adopt
quantum theory in different ways. For each of the approaches
discussed, these imply both problematic and promising features
which will be indicated.