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
Pinky and the Brain question, "Are you pondering what I'm pondering?" Pinky often points out flaws in the Brain's plans, which the Brain consistently ignores. The issues Pinky brings up can ironically lead to the downfall of the given night's plot. He is also arguably Brain's moral compass and only real friend. When Pinky sold his soul to get Brain the world in "A Pinky and the Brain Halloween", Brain saved him because he missed him and the world was not worth ruling without him. Pinky also has shown signs of intelligence despite his supposed childish stupidity. In "Welcome to the Jungle", Pinky was