Brain map represents rat whiskers
Two American scientists have created a detailed brain map representing the neural sensations of rat whiskers.
Mark Andermann from Harvard University in Boston and Christopher Moore from the Massachusetts Institute of Technology in Cambridge had made a stimulator for this purpose, with which each individual whisker could be stimulated separately. Electrodes then picked up the brain's responses.
It was shown that every single whisker precisely finds its counterpart in the primary somatosensory cortex. The respective neurons for a whisker are combined in so-called neuronal columns, with specialized nerve cells for the direction of movement of the whisker.
The representations of the different parts of the body in the cerebral cortex have been known for a long time. There are maps of the human brain that show the regions for the incoming sensory impressions and for the outgoing muscular commands and are known as somatosensory and motor "homunculus".
Brain researchers are also familiar with the arrangement of specialized nerve cells in columns from the visual cortex, where information from the eyes converges. However, rats use their whiskers to orient themselves very well, so their brain devotes a lot of space to these organs of touch.
