Neurobiological aspects of content scanning process in sensory systems

Considering neurobiological aspects of visual system in birds and particularly in owls, echolocation in horseshoe bat and well known visual system in primates/humans we present their common features that concerns content scanning capabilities. In that we see various fulfilments of the same evolutionary concept in quite different ecology frames. Proper comparison is given, showing how sophisticated are certain ecologically determined features of particular scanning process, and its relation to the phenomenon of attention, whatever how highly embedded in brain functions. We gave the explanation of neurobiological background of such mechanism