Sensory maps and brain development

Sensory maps and brain development is a concept in neuroethology that links the development of the brain over an animal’s lifetime with the fact that there is spatial organization and pattern to an animal’s sensory processing. Sensory maps are the representations of sense organs as organized maps in the brain, and it is the fundamental organization of processing. Sensory maps are not always close to an exact topographic projection of the senses. The fact that the brain is organized into sensory maps has wide implications for processing, such as that lateral inhibition and coding for space are byproducts of mapping. The developmental process of an organism guides sensory map formation; the details are yet unknown. The development of sensory maps requires learning, long term potentiation, experience-dependent plasticity, and innate characteristics. There is significant evidence for experience-dependent development and maintenance of sensory maps, and there is growing evidence on the molecular basis, synaptic basis and computational basis of experience-dependent development. Sensory Maps List of known sensory maps: Somatotopic maps: homunculus, rat barrel cortex, star-nose mole nose Retino-topic maps: visual field position, orientation, direction, spatial frequency Tonotopic maps: interaural time difference, frequency tonotopic maps of the cochlea Jeffress model The computational map is the “key building block in the infrastructure of information processing by the nervous system.” Computation defined as the transformation in the representation of information is the essence of brain function. Computational maps are involved in processing sensory information and motor programming, and they contain derived information that is accessible to higher-order processing regions. The first computational map to be proposed was the Jeffress model (1948) which stated that the computation of sound localization was dependent upon timing differences of sensory input.