Proprioception (from Latin proprius meaning one's own) is the sense of one's own body and limb position with the body itself acting as the stimulus rather than extraneous forces, as in the sense of touch. Mediated by unknown mechanically activated ion channels at nerve endings, proprioceptors convey fundamental signals required for basic motor functions such as standing and walking (or as illustrated on the cover, tightrope walking while blindfolded). Woo et al. show that Piezo2 is the mechanically activated ion channel in proprioceptors. The cover was designed by the illustrator Jorge Colombo using finger painting on an iPad. (p 1756).

Patterns of connectivity between activity time courses of distinct brain regions are unique to each individual and can act as an identifying fingerprint. Image from jelen80/iStock/Thinkstock.p 1664

The locus coeruleus is a brainstem nucleus that is important for arousal and learning, alerting the brain to surprising stimuli. Martins and Froemke examined how activation of the rat locus coeruleus leads to long-lasting changes in responses to sounds, affecting auditory perception and modifying the circuitry of the rat auditory cortex and the locus coeruleus itself. The cover is a reference to The Scream of Nature by Edvard Munch.1483

Ten years ago this month, Nature Neuroscience published a paper showing that the microbial protein Channelrhodopsin-2 could drive activity in neurons in response to light. This special anniversary issue presents thoughts from pioneers and users of 'optogenetics' that reflect on its past and future in neuroscience. The cover represents the proliferation and expansion of optogenetics, as alluded to by the spectra of laser beams, commonly used to activate the engineered light-gated proteins, amidst a sea of archeabacteria from which many are derived. Cover design by Alexander Arguello. Image credits: Yang Yu (lasers) and Jezperklauzen (bacteria), iStock/Thinkstock. (pp 1200, 1202 and 1213)

Dysregulation of RNA metabolism contributes to the pathophysiology of amyotrophic lateral sclerosis (ALS). Petrucelli and colleagues profiled the transcriptome of brain samples from ALS patients with or without mutations in C9orf72 and identified distinct RNA profiles and deficits in RNA processing. The cover depicts blue cornflowers, the international symbol of hope for ALS, contributing small droplets of knowledge into a bucket, an allusion to the ice bucket challenge that raised awareness and funding for ALS in August of last year. Cover composite by Squale Productions Inc. and Boris Bulychev/123RF.com. (pp 1066 and 1175)

Stefansson and colleagues found that genetic risk scores derived from large schizophrenia and bipolar disorder genome-wide association studies predict membership in artistic societies and creative professions in Icelandic, Swedish and Dutch individuals. On the cover is a painting (Untitled, 2013) by Icelandic artist Marta Mara Jnsdttir, whose work is filled with bizarre anatomical references and abstract organic forms with a hint of science fiction.928953

Garfield and colleagues demonstrate that melanocortin-4 receptor (MC4R)-expressing neurons of the paraventricular nucleus of the hypothalamus (PVH) are required for the bidirectional control of feeding and that they induce satiety associated with an appetitive state. The cover depicts a stylized immunofluorescence image of MC4R-expressing neurons in the PVH (as demarked by an MC4R-t2a-Cre reporter line). It symbolizes both the PVH as the 'heart' of the hypothalamic feeding circuitry and the positive emotional valence of the MC4R-driven satiety. Cover design and concept by Michael J. Krashes and Alastair S. Garfield.789863

Sequencing the exomes of patients with the motor neuron disease amyotrophic lateral sclerosis (ALS), Weishaupt and colleagues provide evidence that loss-of-function mutations in TBK1 cause familial cases of ALS and fronto-temporal dementia. The cover depicts TBK1 as yet another piece in the complex puzzle that is ALS genetics. Cover design by Erin Dewalt, concept by Alexander Arguello. Image from ThinkStock.611631

Recording from populations of head-direction cells across brain states, Peyrache and colleagues provide an experimental demonstration of the existence of a self-organized ring attractor: the sequential activity of head-direction neurons observed in the waking mouse persists during sleep, and this 'neuronal compass' always points toward well-defined directions. The cover depicts the probabilistic compass 'needle' (heat map ring) decoded from neuronal activity as the animal is exploring its environment. Cover design by Erin Dewalt, concept by the authors. Images provided by the authors and ThinkStock.482569

Epilepsy is a chronic neurological disorder characterized by aberrant neural activity. In this special focus issue on epilepsy, we highlight recent research into the pathogenic events and circuit-level changes driving pathological alterations in neuronal excitability. The cover depicts parallels between seismic activity and epileptic seizures. They each start focally but have widespread effects that can be devastating, leaving long-term damage both at the site of initiation and elsewhere.331–372

Murphy-Royal and colleagues find that glutamate release increases the diffusion of the astrocytic glutamate transporter GLT-1 in the plasma membrane. This activity-dependent increase in mobility facilitates glutamate clearance from the synaptic cleft, which influences the kinetics of excitatory post-synaptic events in rat hippocampal neurons. The cover shows astrocytes immunolabeled for GFAP.166219

Dadarlat and colleagues deliver artificial sensorimotor feedback to monkeys via spatiotemporally patterned electrical microstimulation on eight electrodes in somatosensory cortex. This feedback signal is integrated with natural vision in a statistically optimal manner. The cover evokes the image of a monkey's real sensory world blending with the virtual one created by experimenters.p 138