Volume 554 Number 7692

Editorials

SpaceX ignites big dreams p.275

The successful launch of the Falcon Heavy rocket was a stunning moment that opens the way for commercial exploration of deep space.

doi: 10.1038/d41586-018-01877-7

News

Trump science budget sows confusion p.284

US president makes last-minute decision to abandon proposal for major cuts to National Institutes of Health, National Science Foundation and Department of Energy’s science office.

doi: 10.1038/d41586-018-01985-4

News Features

News & Views

The origin of pulsating auroras p.302

Spectacular light shows in Earth’s atmosphere called pulsating auroras are directly linked to processes in space. After decades of research, the full chain of events that creates such auroras has been observed.

doi: 10.1038/d41586-018-01669-z

Brainpower boost for birds in large groups p.303

Whether intelligence is selected for in species that have a complex social life is debated and hard to test. Cognitive performance and associated reproductive success are now linked to group size in wild magpies.

doi: 10.1038/d41586-018-01487-3

Burst firing sets the stage for depression p.304

Salvos of neuronal activity in the brain’s lateral habenula, regulated by astrocyte cells, drive depression-like behaviours in rodents. The finding might help us to understand one antidepressant and to develop more.

doi: 10.1038/d41586-018-01588-z

Working memory freed from the past p.306

Working memory is influenced by past experiences. An area of the rat brain has now been identified that represents recent history — silencing this area can remove biases from working memory and decision-making.

doi: 10.1038/d41586-018-01418-2

The two faces of a magnetic honeycomb p.307

Quantum spin liquids are long-sought exotic states of matter that could transform quantum computing. Signatures of such a state have now been observed in a compound comprising iridium ions on a honeycomb lattice.

doi: 10.1038/d41586-018-01747-2

On the trail of invasive cells in breast cancer p.308

During breast-cancer progression, tumour cells that arise in the milk duct spread elsewhere in the breast. The origin of these invasive tumour cells is now revealed by an analysis of spatially defined single cells.

doi: 10.1038/d41586-018-01634-w

Articles

Letters

Freezing on a sphere p.346

Freezing on a spherical surface is shown to proceed by the sequestration of defects into 12 icosahedrally coordinated ‘seas’ that enable the formation of a crystalline ‘continent’ with long-range orientational order.

doi: 10.1038/nature25468

Posterior parietal cortex represents sensory history and mediates its effects on behaviour p.368

Many models of cognition and of neural computations posit the use and estimation of prior stimulus statistics: it has long been known that working memory and perception are strongly impacted by previous sensory experience, even when that sensory history is not relevant to the current task at hand. Nevertheless, the neural mechanisms and regions of the brain that are necessary for computing and using such prior experience are unknown. Here we report that the posterior parietal cortex (PPC) is a critical locus for the representation and use of prior stimulus information. We trained rats in an auditory parametric working memory task, and found that they displayed substantial and readily quantifiable behavioural effects of sensory-stimulus history, similar to those observed in humans and monkeys. Earlier proposals that the PPC supports working memory predict that optogenetic silencing of this region would impair behaviour in our working memory task. Contrary to this prediction, we found that silencing the PPC significantly improved performance. Quantitative analyses of behaviour revealed that this improvement was due to the selective reduction of the effects of prior sensory stimuli. Electrophysiological recordings showed that PPC neurons carried far more information about the sensory stimuli of previous trials than about the stimuli of the current trial. Furthermore, for a given rat, the more information about previous trial sensory history in the neural firing rates of the PPC, the greater the behavioural effect of sensory history, suggesting a tight link between behaviour and PPC representations of stimulus history. Our results indicate that the PPC is a central component in the processing of sensory-stimulus history, and could enable further neurobiological investigation of long-standing questions regarding how perception and working memory are affected by prior sensory information.

doi: 10.1038/nature25510

Asparagine bioavailability governs metastasis in a model of breast cancer p.378

In a mouse model of breast cancer, asparagine bioavailability strongly influences metastasis and this is correlated with the production of proteins that regulate the epithelial-to-mesenchymal transition, which provides at least one potential mechanism for how a single amino acid could regulate metastatic progression.

doi: 10.1038/nature25465