Research articles

This study describes how interactions between DOCK7 and TACC3 are key to the switch from proliferation to differentiation in developing radial glial progenitor cells (RGCs). DOCK7 exerts its effects via interactions with the centrosome-associated protein TACC3, and these interactions are likely to modulate the RGCs' apically directed interkinetic nuclear migration.

In this study, the authors show that two K⁺ channels, SK3 and GIRK, are important for the pheromone-induced activation of olfactory neurons in the vomeronasal organ (VNO). In addition, they show that K⁺ ion concentrations are maintained at high levels in the VNO lumen, permitting inward K⁺ flux through these channels.

Using simultaneous electrophysiological and optical imaging, this study finds that it is the linear summation of stimulus-independent trial-related and stimulus-dependent components that yield the signal seen in neuroimaging studies. However, the trial-related component, which does not correlate with neural spiking or LFPs, can account for over half of the neuroimaging signal, suggesting that it is crucial to take this component into account when interpreting neuroimaging studies.

The authors found that, when monkeys detected a salient stimulus defined purely by bottom-up factors, neurons in the dorsolateral prefrontal cortex represented the stimulus no later than those in the posterior parietal cortex. The results suggest an early involvement of the prefrontal cortex in the bottom-up guidance of visual attention.

Here the authors show that the binding of amyloid-β (Aβ) oligomers to cellular prion protein (PrPc) activates Fyn kinase. Aβ stimulation of PrPc/Fyn signaling drives phosphorylation of the NR2B subunit of NMDA receptors, with a subsequent loss of receptor surface expression and dendritic spines.

Using a novel spatial discrimination task, Bannerman and colleagues show that mice lacking hippocampal NMDA receptors in dentate gyrus and CA1 can encode and store spatial memories normally but fail to use this spatial knowledge to select appropriate responses from ambiguous choices.

In this study, the authors show that neocortical neural precursor cells exhibit progressively condensed chromatin as they lose neurogenic potential during development. Furthermore, the open chromatin state of early stage progenitors is regulated by the high mobility group A (HMGA) proteins.

In this study, the authors show that spontaneous calcium spiking activity in thalamocortical neurons modulates the rate of axonal growth during development via regulation of Robo1 transcription.

This study describes burst-dependent protection from synaptic depression, which maintains responsiveness to behaviorally important stimuli in Aplysia. In this attention-like mechanism, PKC at sensory neuron synapses discriminates the precise pattern of firing, preventing these release sites from becoming silenced during repeated tactile stimuli when these stimuli are salient.

The authors find that aged mice have decreased expression of the DNA methyltransferase Dnmt3a2 in the hippocampus. Rescue of Dnmt3a2 expression in aged mice reversed learning and memory deficits, whereas decreasing Dnmt3a2 expression in young mice impaired memory formation.

In a longitudinal brain imaging study, patients with subacute back pain were followed over the course of 1 year. Initially greater functional connectivity of nucleus accumbens with prefrontal cortex predicted pain persistence, implying that corticostriatal circuitry is causally involved in the transition from acute to chronic pain.

By tracking brain activity in both normal subjects and in epilepsy patients, the authors demonstrate that there are differences in the time courses of activation to a memory task in the perirhinal cortex and the hippocampus. These results suggest differentiated roles for these two areas during memory tasks.

Here the authors find that auditory cues presented quietly during a nap influence motor sequence learning. When one of two sequences was cued following initial learning, performance was disproportionately improved for that sequence, reflecting sleep-based reactivation and consolidation of skill memory.

In this study, the authors show that optogenetic silencing of neurons with a commonly used light-driven chloride pump can result in alterations in GABAergic synaptic transmission that persist after the stimulation period and that may result in changes to neuronal excitability.

The projection from the lateral habenula (LHb) to the rostromedial tegmental nucleus (RMTg) transmits negative reward–related information. Here the authors show that aversive stimuli increase LHb excitatory drive onto RMTg neurons, and optogenetic stimulation of this pathway is sufficient to induce active, passive and conditioned behavioral avoidance.

AgRP neurons in the hypothalamus elicit feeding behavior. Here the authors show that interfering with AgRP neuron function, either by selective knockout of Sirt1 or by early postnatal ablation, leads to increased exploratory behavior and enhanced response to cocaine, which is associated with increased forebrain dopamine levels.

The authors show that the microRNA miR-7a fine-tunes the expression of the transcription factor Pax6, generating a dorsal-ventral gradient that controls differentiation of olfactory bulb precursors into dopaminergic neurons.

Using patterned optogenetic stimulation and chronic in vivo imaging of dendritic spines, this study shows that the precise pattern of neural spiking—rather than total number of spikes—is the major determinant of dendritic spine stability in cortical pyramidal neurons.

Here the authors show that ventromedial prefrontal cortex (vmPFC) levels of GABA and glutamate in human volunteers are predictive of both behavioral performance and the dynamics of a neural value comparison signal in a manner as predicted by models of decision-making, thus providing evidence for neural competition in vmPFC supporting value-guided choice.

This paper reports that hippocampal theta sequences and their corresponding spatial paths stretch forward or backward as a function of an animal's behavior and that these firing sequences map the environment in segments of variable lengths or 'chunks'.