Credit: Bing Ye (CC-BY 4.0, https://creativecommons.org/licenses/by/4.0/)
An inhibitory neuron called chandelier cell in the cerebral cortex of a mouse. Chandelier cells send dendrites (input apparatus) toward the surface of, and axons (output apparatus) toward the inside of, the cerebral cortex. Liu et al. report that the extra copy of the DSCAM gene in mouse models of Down syndrome increases the number of the axon terminals of chandelier cells.