Reviews & Analysis

The neural basis of aggression is poorly understood. A study in this issue used genetic scalpels to dissect the circuitry of the fly brain and identified a small cluster of octopaminergic neurons that can make a fly fighting mad.

Mitogen-activated Protein Kinases (MAPKs) are critical for the formation of stable long-term memories. New work shows that circadian MAPK activity cycling is important in the formation of new hippocampus-dependent memories.

A new study identifies pikachurin, a previously-unknown dystroglycan-binding protein that is critical for the apposition of photoreceptor and bipolar cell dendrites at the ribbon synapse. This work could explain some of the visual defects seen in several muscular dystrophies.

A study uses electrophysiological recordings from primary visual cortex of the monkey to demonstrate that the effects of attention are modulated by task difficulty and that two different neuronal populations mediate this effect.

The transcription factor hypoxia-inducible factor 1 (HIF-1) triggers multiple cellular responses to cope with hypoxia. A study in this issue suggests that elevated HIF-1 also causes axon guidance defects under hypoxic conditions.

Two new studies in Science and Nature Neuroscience combine functional magnetic resonance imaging and electrical microstimulation to reveal face-selective temporal and frontal areas and their connectivity.

Drugs of abuse are known to induce changes in synaptic strength in the reward neurons of the brain. Two recent studies shed some light on how drug-induced plasticity might mediate addictive behavior long after drug use.

Have facial expressions evolved randomly or do their different shapes support some adaptive purpose? New work offers evidence of a selection pressure that may have shaped fearful and disgusted expressions.

Although voltage-clamp recordings remain a favorite method for studying synaptic transmission, the space-clamp problems that are associated with somatic voltage-clamp recordings have never been directly measured. A study by Williams and Mitchell in this issue now measures the experimental errors associated with this technique.

Pascual et al. conditionally delete glial cell line-derived neurotrophic factor (GDNF) expression in adult mice. They report that GDNF is indispensable for the survival of adult catecholaminergic neurons.

Decisions between two alternatives have been extensively studied and modeled. A study now reports that during choices among several options, the responses of neurons in the lateral intraparietal area are still well described by the integration-to-bound model, supporting the general applicability of this computational framework.

A new study shows that microRNA-9 regulates multiple processes near the organizing centers during early brain development in zebrafish, revealing previously unknown modes of action for microRNAs in the nervous system.

Neurotrophins are recognized for their role in sustaining neuron survival and promoting axon growth. New studies reveal that they can also facilitate both neuron death and axon pruning by mechanisms that have much in common.

A new study in Nature finds that the retinal pathway transducing lighting information to the circadian clock is anatomically wholly independent of the visual pathways.

Many kinases have been implicated in memory formation, but a new study suggests that a phosphatase, calcineurin, is important for the long-lasting nature of emotional memories by making them resistant to extinction.

Animals can discriminate between olfactory stimuli, but they perceive different concentrations of a chemical as one stimulus. A recent study suggests how this happens and reveals a neural circuit that mediates olfactory gain control.

'What' and 'where' pathways are recognized in the visual system, but do they exist in auditory cortex? A new study uses reversible inactivation to demonstrate a double dissociation between two cortical regions in two tasks.