Final answer:
Stage 1 sleep is a very light stage of sleep with easily awakenable conditions, characterized by relaxed brain wave activity including alpha and theta waves.
Step-by-step explanation:
Stage 1 sleep is indeed considered a very light sleep during which individuals can be easily awakened. This initial phase of sleep is characterized by a decrease in overall muscle tension and a drop in core body temperature. While in stage 1 sleep, the brain produces alpha waves and theta waves, both of which are associated with a relaxed state of mind. Alpha waves, which are present at the onset of stage 1, are similar to the brainwave activity of a relaxed and awake person, though they have less variability and are lower in frequency. As one progresses deeper into stage 1 sleep, theta wave activity increases, featuring even lower in frequency and higher in amplitude than alpha waves. Because of the lightness of this sleep stage, individuals who are awakened from it may not feel as if they were asleep at all.