What is a dream? How is the word “dream” defined?
The word “dream” has four interrelated meanings that follow one from another. When we put them altogether, we know what a dream is. First, a “dream” is a form of thinking that occurs when (a) there is a certain, as yet undetermined, minimal level of brain activation, and (b) external stimuli are blocked from entry into the mind, and (c) the system we call the “self system” (the “I,” the “me”) is shut down. This may seem overly complicated, but it is worded this way because we don’t just dream during sleep, but also on some occasions in very relaxed waking states when we “drift off” and suddenly realize we have been dreaming. Two careful studies have shown that people are awake (by EEG criteria) during these episodes. (The fact that we don’t need to be asleep in order to dream may have some important implications. For example, it favors a “cognitive” theory of dreams over theories that talk about neurophysiological or neurochemical changes during sleep that supposedly produce dreams.
