This allows the hypothalamus to regulate daily rhythms such hunger and the reticular formation to regulate daily sleep rhythms. Sleep is an essential part of life, but do we know why we fall unconscious for thirty percent of the day? A variety of theories have been made for the need for sleep. One from an evolutionary point of view proposes that sleep was a way that animals …show more content…
We travel through various stages of sleep during the night, but one of the deepest stage of sleep is REM (rapid eye movement) sleep which is an active stage of sleep. Civilizations have wondered about dreams for millennia, most thinking they foretold the future. However, today scientists and psychologists theorize the causes of dreams. Sigmund Freud, a prominent psychologist of the late 19th century, theorized that dreams are the reflections of the subconscious. Freud believed that dreams could be analyzed to reveal hidden desires and wishes. Freud distinguished the material of dreams are manifest content and latent content. He believed that manifest content was the dream 's surface content while latent content was the subconscious meaning. As technology and science grew, other theories on dreams were produced. The cognitive theory uses the same concepts of analyzing the waking brain as on dreams; this theory states that dreams are essentially subconscious cognitive processing. Contrary to Freud 's view of dreams, the cognitive theory does not believe in the hidden or symbolic meanings of dreams. The cognitive theory believes dreaming is not different from the waking mind and uses the term "default network" which refers to a collection of neurons that are active during daydreaming and whenever we are not focused on a