Multiple frontal cortical areas have been implicated in value-based decision-making, but their relative contributions are unclear. Kennerley and colleagues report a double dissociation in the neural correlates of decision-making, with orbitofrontal cortex neurons encoding choice value relative to recent choice values and anterior cingulate cortex neurons encoding multiple decision parameters and reward prediction errors.14911581

Interactions between neurons, glia and vasculature are critical for the maintenance of normal brain function. We present a special focus on the growing field of neurovascular interactions comprising reviews and perspective articles highlighting the latest advances in our understanding of these interactions, with particular emphasis on their roles in health and disease. The cover depicts a confocal image composite of perivascular migration of implanted human glial progenitor cells, xenografted into the rodent brain, courtesy of Takahiro Takano, Maiken Nedergaard and Steven Goldman.13531363–1405

Guo et al. provide the first genome-wide, single-nucleotide resolution, quantitative characterization of the epigenetic DNA methylome in mature neurons in vivo in response to neuronal activation. This reveals a surprisingly dynamic nature of the DNA methylation landscape in neurons.p 1345

Using silicone electrodes that can sample neurons in different layers along the length of the electrode, Mizuseki et al. find a qualitative difference in the in vivo firing pattern of pyramidal neurons in the deep versus superficial dorsal CA1 layer of the rat hippocampus. The cover depicts a Gallyas silver stained hippocampal slice after transient forebrain ischemia. The picture was taken using dark field illumination.1174

Owls accurately localize sound sources near the center of gaze, but systematically underestimate peripheral source directions. The authors demonstrate that this behavior is predicted by statistical inference and show that the owl's map of auditory space decoded by a population vector is consistent with the behavioral model.Cover photo by Jan Tyler, from istockphoto.9431061

Ringach and Paik demonstrate that orientation maps, as found in the cortex of higher mammals, are likely to arise from the spatial layout of retinal ganglion cell receptive fields in the retina. The predictions of this model are borne out in four different species.803919

Calcium-activated chloride currents are thought to amplify the olfactory signal during the transduction process. Surprisingly, disruption of Ano2, a critical channel in both the main olfactory epithelium and vomeronasal organ, did not reduce performance in an olfactory behavioral task. The cover image shows posterior mouse nose with acetylated tubulin labeled in red and Ano2 labeled in green; sensory neurons of the olfactory epithelium appear yellow owing to coexpression of both proteins.p 763

The authors report that radial glia–like (oRG) progenitor cells are present in the mouse embryonic cortex and that these cells arise from asymmetric divisions of radial glia. In turn, they undergo asymmetric divisions to generate neurons. The cover depicts events occurring during cortical cell migration and development (oRG cells in red, radial glia cells in blue, neurons in green).538555

Mice without the chloride channel CLC-3 have hippocampal degeneration. Riazanski and colleagues now show that CLC-3 mediates neurotransmitter loading of synaptic vesicles by acidification. The cover image is an electron micrograph of inhibitory synaptic vesicles isolated from mouse brain captured on microbeads coated with antibody to VGAT.405487

In Drosophila, R7 and R8 photoreceptors, which detect different wavelengths, form synapses in distinct medulla layers. The authors report that the interaction of Golden Goal and Flamingo (two cell-surface proteins involved in photoreceptor targeting)specifies synaptic-layer selection of photoreceptors. On the cover is a cross section of the adult fruit fly visual system, showing photoreceptor (green) axon projections to optic ganglions, which are surrounded by brain cells (neuronal nuclei in red and glia in blue).p 314

Hunger makes Drosophila larvae move faster in search of food. Koon and colleagues show that starvation increased branching of octopaminergic motor neurons' axonal terminal arbors, driven by octopamine released from these same motor neurons. The increased locomotor activity of starved larvae required octopaminergic signaling. On the cover is a drawing by Vivian Budnik.124190

The patterns of nociceptive innervation in skin and spinal cord differ in mammals and lower vertebrates. Guo et al. report that nerve growth factor induces the transcription factor Hoxd1 in mouse, but not chick, sensory neurons and that expression of Hoxd1 is necessary and sufficient for a mammalian-like pattern of nociceptive projections in vivo. On the cover is a section of adult mouse dorsal root ganglion and its associated spinal nerves. Antibodies for CGRP (red), IB4 (green) and Vglut1 (blue) stain three different classes of somatosensory neurons and their axons.

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