Prenatal activity from thalamic neurons governs the emergence of functional cortical maps in mice

Abstract

Brain map of touch sensation The brain's somatosensory cortex contains a topographical map that reflects touch sensation inputs. During embryonic development, axons from the midbrain thalamus build columnar connections to the cortex in the absence of sensory input. Working in mice, Antón-Bolaños et al. found that these thalamocortical connections are responsible for organizing the somatosensory cortex (see the Perspective by Tiriac and Feller). Organization of the map in the cortex depends on spontaneous calcium waves in the embryonic thalamus. Thus, the somatosensory map is sketched out before actual sensory input begins to refine the details. Science , this issue p. 987 ; see also p. 933