From Medical Xpress:
Temporal lobe lateral view. Credit: BodyParts3D/Anatomography via wikimedia, CC BY-SA
Rapid eye movements (REMs) during sleep may contribute to the visual part of our dreams by acting as a switch from image to image, researchers have found. The study, which measured the activity of individual cells in the brain in both awake and sleeping participants, is important because it is the first of its kind and provides a great starting point for uncovering the deeper secrets of human consciousness.
Consciousness can roughly be summed up as our awareness of the environment and our ability to respond to it. However, Sigmund Freud and his followers have described dreams as deep-seated, unconscious psychic desires. Today, many instead see them as an interpretation of images of the environment stored in certain parts of the brain. These images are thought to be projected onto the visual cortex so we can “see them” in our dreams.
Physiologists and experimental psychologists refer to mental images of 3D scenes as “visuospatial imagery”, which is similar to what we see when we dream. In humans, we know that direct stimulation of certain areas in the brain in epileptic patients induces dream-like images. However, combining the interpretations of dreams according to Freud with the physiological basis of dreaming into a single study is a challenging task.
The new study is based on measurement from electrodes implanted in the brains of humans for the first time, giving firsthand information about how single neurons behave in dreaming humans.