In this issue, Philippidou and colleagues show that Hox5 genes are essential for the organization, survival and axonal branching of motor neurons required for breathing. Unexpectedly, this requirement for Hox5 activity persists to later developmental stages. On the cover is a whole-mount staining of an E12.5 Hb9::GFP embryo. The two sides are mirror images, but the phrenic nerve on the right site has been artificially thinned to represent the Hox5 mutant mouse phenotype. Superimposed are wild-type and mutant diaphragms of E18.5 whole-mount images.16071636

Kim and colleagues used computer rendering techniques to show that the appearance of gloss in two-dimensional images does not solely depend on locally bright highlights, as was previously thought, but also depends on appropriately formed dark reflections. The cover shows an example of an image in which locally dark regions promote the compelling appearance of surface gloss.1590

The increasing prevalence of obesity around the world has added a degree of urgency to research into how and why humans overeat and become obese. We present a special focus issue summarizing recent work on the neural control of feeding behavior and how its disruption might lead to obesity. Cover design by Jamel Wooten, based on an image from istockphoto.com.13211330–1355

Enomoto and colleagues observe that, during the development of the enteric nervous system, a subset of enteric neural crest cells use trans-mesenteric migration to colonize the caudal hindgut. This migration requires GDNF and GFRα1 signaling. The cover depicts the developing mouse gut with migrating enteric neural crest-derived cells in green and vascular endothelial cells in red. In the background is an image of the mature mouse gut and enteric nervous system stained for acetylcholinesterase in blue-gray.p 1211

Damage or disease in the nervous system is often accompanied by inflammation and an immunological response that requires a carefully choreographed and reciprocal interplay between the neural and immune systems. We present a special focus issue on neuro-immune interactions that highlights some of the most recent and interesting research aimed at understanding the relationship between neural processes and immune reactions. The cover image is an illustration of the reciprocal communication between blood-borne immune cells and neural stem/progenitor cells in the injured brain by Bengt Mattsson.10551063

Using functional and morphological analysis, Holderith and colleagues demonstrate that the release probability and the number of voltage-gated calcium channels are linearly correlated with the size of the active zone in CA3 pyramidal cell recurrent axon terminals. On the cover is a freeze-fracture immunogold electron microscopy image of a CA3 synaptic terminal.928988

Using cell type–specific expression and activation of channelrhodopsin-2 in the dorsomedial striatum, Kravitz et al. demonstrate that stimulation of direct pathway medium spiny neurons can reinforce operant behavior in awake behaving mice whereas activation of indirect pathway medium spiny neurons punishes operant behavior.807816

How does the brain implement social processes and behavior, and how do these processes in turn modify the brain? We present a special focus issue summarizing some of the most current research aimed at answering these questions, both in humans and in animals. Cover design by Erin Dewalt, based on images from istockphoto.com and an original idea suggested by Niall Bolger and Jamil Zaki.p 645

Marsicano and colleagues report that the type-1 cannabinoid receptor (CB1) is present in mouse neuronal mitochondrial membranes, where it regulates cellular respiration and energy production in the brain. On the cover is an electron microscope image of mouse hippocampus with immunogold staining for CB1 on neuronal mitochondria.499558

Applying cell type–specific optical and pharmacogenetic techniques to the mouse hippocampus in vitro, Lovett-Barron and colleagues show that dendritic inhibition of CA1 pyramidal cells regulates the transformation of synaptic input into action potential output by gating local dendritic electrogenesis. The cover depicts the CA1 region of the dorsal hippocampus, with the sources of synaptic excitation (CA3 Schaffer Collateral axons; green) and inhibition (local GABAergic interneurons; red) to CA1 pyramidal cells.346423

Hobert and colleagues report that the transcription factor UNC-3 acts via a common cis element to regulate the battery of genes that confer cholinergic identity on a subset of motor neurons in the nematode. On the cover is an image of C. elegans ventral nerve cord, with cholinergic motor neurons labeled in green and muscles in red.205

Using a membrane-tethered, genetically encoded Ca2+ indicator, the authors describe a novel Ca2+ signal in hippocampal astrocytes that are mediated by astrocytic TRPA1 channels. Decreasing this Ca2+ signal decreased interneuron inhibitory synapse efficacy by reducing GABA transport through GAT-3. On the cover is an image of cultured astrocytes, immunostained for GFAP (green), S100β (red) and DAPI (blue).370