Review Articles

The energy homeostasis system maintains stability of body fat stores over time but can be overridden by activation of feeding neurocircuits during emergent or stressful conditions. In this Review, Schwartz and colleagues highlight crosstalk between homeostatic and emergency feeding circuits in the regulation of energy balance.

Recent work has identified novel modifiers of axon degeneration following injury, known as Wallerian degeneration, and new examples of convergence between this mechanism and axon degeneration occurring in some neurodegenerative diseases. Coleman and colleagues outline our current understanding of the Wallerian degeneration pathway and consider its links to disease mechanisms.

JUN amino-terminal kinases (JNKs) regulate various processes in neurodevelopment and the adult brain. In this Review, Coffey examines the neuronal functions of JNKs and the therapeutic potential of targeting these kinases in various diseases of the nervous system.

Intracortical brain–machine interfaces with sensorimotor cortices are one approach by which a person can exert voluntary control over a prosthetic limb or paralysed muscles. In this Review, Bensmaia and Miller review recent achievements and remaining challenges in the development of intracortical brain–machine interfaces.

Microglia and macrophages have crucial roles in nervous system development, maintenance and disease. In this Review, Prinz and Priller describe recently discovered details of the embryonic origins and functions of microglia that distinguish them from the other macrophage populations that reside in the brain.

The size and the extent of gyrification of the cerebral cortex both influence brain function in mammals. In this Review, Sun and Hevner examine the mechanisms underlying cortical growth and folding, and discuss how dysfunction in these processes leads to cortical malformations.

The unfolded protein response (UPR) is a homeostatic mechanism by which cells regulate levels of misfolded proteins in the endoplasmic reticulum (ER). Here, Hetz and Mollereau provide an overview of the most recent findings addressing the relevance of ER stress in the nervous system.

Synaptic transmission occurs through two main modalities — namely, chemical and electrical transmission. In this Review, Pereda discusses the complex nature of electrical transmission and explores the mounting evidence that chemical and electrical synapses functionally interact both during development and in adulthood.

Many physiological and anatomical parameters in the brain have a skewed distribution. Buzsáki and Mizuseki propose that this reflects a fundamental aspect of brain organization — namely, a network in which a minority of neurons does most of the work all of the time.

This Review examines recent studies showing that music modulates activity in core brain structures involved in the processing of emotion. The ability of music to change activity in these structures has implications for the development of music therapies in the treatment of various neurological and psychiatric disorders.

In neurons, gephyrin self-assembles into a protein scaffold that interacts with the cytoskeleton and anchors glycine and type A GABA receptors at postsynaptic sites. Tyagarajan and Fritschy review the formation and regulation of these scaffolds and how they in turn regulate inhibitory synapse formation and function.

Memories are thought to be represented in the brain by the 'memory trace' — altered levels of activity in specific neurons and synapses in a neural network. In this Review, Silva and colleagues discuss emerging evidence that the neurons and synapses involved in encoding a particular memory are not random but are specifically 'allocated' based on complex molecular signatures that are determined by the recent activity history of the neuron.

The roles of melanocortins extend well beyond the regulation of energy homeostasis. In this article, the authors review their involvement in different pathophysiological states, which could lead to the development of improved therapeutics for pain and mood disorders, and cognitive impairments.

In vivointracellular recordings and imaging of synaptic activity are revealing how sensory information is conveyed and processed in the brain. This article explores how dynamic interactions between evoked synaptic inputs and their integration within individual neurons generates sensory signalling in the cerebellar and cerebral cortices.

Since their discovery in 2002, inflammasomes have been shown to be crucial mediators of caspase 1 activation, interleukin-1β and interleukin-18 release, and pyroptotic cell death. This Review describes our current understanding of the functions of different inflammasomes in the CNS and their roles in neurological diseases.

To enable the complex neural circuitry found in vertebrates, many axons undergo extensive branching. Here, Kalil and Dent review the roles of extracellular cues, intracellular signalling pathways, cytoskeletal dynamics and neuronal activity in axon branching and terminal arbor formation in the vertebrate CNS.

Itch — the sensation that induces the desire to scratch — results from activity in a subset of nociceptors, all of which also respond to painful stimuli. LaMotte and colleagues describe the studies that have begun to pinpoint the molecular transducers and neural pathways that transmit itch and the coding mechanisms that distinguish it from pain.

After nerve injury, signals from the lesion site must reach the nucleus in order to initiate the transcriptional responses required for regeneration. In this Review, Rishal and Fainzilber describe recent developments in our understanding of the molecular basis of this retrograde injury signalling system.

During development, individual neural progenitors give rise to a series of distinct types of neural progeny that are produced in a specific temporal order. Kohwi and Doe discuss how temporal neural patterning is dictated by extrinsic and intrinsic cues known as temporal-identity factors, as well as by changes in progenitor competence in response to these factors.

Newly generated glutamatergic synapses lack functional AMPA receptor-mediated transmission. Depending on the type of activity that these newborn AMPA-silent synapses are exposed to, they are eventually either eliminated or stabilized. Hanseet al. review recent studies on the abnormal generation of AMPA-silent synapses and on premature or delayed unsilencing that highlight their role in brain pathology.