Sensory maps and brain development the midbrain auditory nucleus had receptive fields independent of nature and intensity of the sound. Roger Sperry proposed a chemical gradient model for eye rotation and for neuronal wiring diagram. Retinal neurons and target cells had identification tags in the form of chemical gradients so that the projection of neurons would be orderly. For a topographic map of the visual world, the map first forms during neural development via molecular signals, such as chemospecific matching between molecular gradients. The molecular basis of sensory maps and brain development is a field that is being actively explored. The most recent work has
The Stealers of Dreams typical. Then the Doctor is there, and asks to talk to him, go into the building and try to help. Once the Doctor gets inside, Jack fills him in on what's happening. Rose is in a room, still unsure of herself. The Doctor tells her about the microorganisms, how they feed off electrical activity, and seem to just love the neuroelectro-chemical signals put out by the right side of adult human brains. They create a feedback loop, which passes to the left side and causes a person to become 'fantasy-crazy.' He tells her that now that she understands what is