Is areal extent in sensory cerebral cortex determined by peripheral innervation density?
The whisker-to-barrel pathway of mice (an important component of the animal's somatosensory system) was studied in two experiments. In one, the cortical representation of a row of whiskers was caused to be larger by lesioning a neighbouring row of follicles, while the innervation density remained unchanged. In the second experiment mice, selectively bred for particular whisker and barrel patterns, showed for their supernumerary vibrissal follicles a relatively large cortical representation. On the basis of the second experiment we formulate a possible role of the sensory periphery in brain evolution.
D000818:Animals; D001931:Brain Mapping; D051379:Mice; D008813:Mice, Inbred ICR; D011984:Sensory Receptor Cells; D013003:Somatosensory Cortex / Q000033:anatomy & histology*; D014738:Vibrissae / Q000033:anatomy & histology*