Your post proved very interesting to me, There is dream state at the REM level.. From what I know, it is not always possible to dream in stage 1 & 2. I have had similar when I have woken in my dream.. I put it down to being part of my DREAM. Your friend may be becomming more aware of her sleep and ergo, able to 'steer her dreams'. dreams and the sub-conscious fascinate me.. here I have included the levels to 'normal sleep'
During a normal nights sleep a sleeper passes from the theta waves of stage 1 and 2, to the delta waves of stage 3 and 4. Delta waves are the slowest and highest amplitude brain waves. There is no real division between stages 3 and 4 except that, typically, stage 3 is considered delta sleep in which less than 50 percent of the waves are delta waves, and in stage 4 more than 50 percent of the waves are delta waves. Delta sleep is our deepest sleep, the point when our brain waves are least like waking. Consequently, it is most difficult stage in which to wake sleepers, and when they are awakened they are usually sleepy and disoriented. Interestingly, delta sleep is when sleep walking and sleep talking is most likely to occur.
Besides these four basic stages of sleep, another, unique, stage of sleep exists, REM. This stage gets its name from the darting eye movements that accompany it (rapid eye movement), as indicated by the EOG. Interestingly, it is also characterized by a sudden and dramatic loss of muscle tone, which is measured by the EMG. In fact, the skeletal muscles of a person during REM sleep are effectively paralyzed. This stage is also, associated with a unique brain wave pattern too, in that during REM sleep a sleepers brain waves demonstrate characteristics that are similar to waking sleep, a combination of alpha, beta, and desynchronous waves (see Figure 1). Most importantly to psychologists, this is the stage of sleep most associated with dreaming. When a sleeper in a research lab begins to exhibit the physiological indices of R.E.M sleep, and they are awakened, the great majority of the time they will report that they were having a vivid, story-like, dream. During other stages, on the other hand, they normally do not report dreaming.
In a normal night's sleep, a sleeper begins in stage 1, moves down through the stages, to stage 4, then back up through the stages, with the exception that stage 1 is replaced by REM, then the sleeper goes back down through the stages again. One cycle, from stage 1 to REM takes approximately ninety minutes. This cycle is repeated throughout the night, with the length of REM periods increasing, and the length of delta sleep decreasing, until during the last few cycles there is no delta sleep at all.
More info can be found at;
http://web.umr.edu/~psyworld/sleep_stages.htm
