News & Views

Studying the natural wanderings of the living brain is extremely challenging. Bolt et al. describe a new framework for considering the brain’s intrinsic activity based on the geophysical concepts of standing and traveling waves.

A new study shows that infra-slow cortical norepinephrine oscillations shape the micro-structure of sleep and transitions to micro-arousals, wakefulness or rapid eye movement (REM) sleep. Prolonged descending phases of these oscillations promote the occurrence of spindle-rich intermediate sleep, which is involved in memory consolidation.

During cortical development, the generation of neurons from progenitors coincides with increasing vascularization and oxygen levels in the fetal brain and the transition from anaerobic to aerobic metabolism. Dong et al. identify lactate, a metabolite of anaerobic glycolysis, as a multifunctional regulator that coordinates synchrony of cortical neurogenesis and angiogenesis.

Epilepsy is the most common childhood neurological disease, and nearly 20% of affected children develop drug-resistant childhood epilepsy (DRCE). Using single-cell analysis methods, Kumar et al. have identified pro-inflammatory interactions between microglia and T cells in brain tissue from individuals with DRCE. This work may help to identify therapeutic targets for DRCE.

The solutions found by neural networks to solve a task are often inscrutable. We have little insight into why a particular structure emerges in a network. By reverse engineering neural networks from dynamical principles, Dubreuil, Valente et al. show how neural population structure enables computational flexibility.

How and where negative affect is represented in the brain is a central neuroscientific question. A new study identifies neural correlates of both general negative affect and those specific to stimulus type by conducting multimodal functional MRI experiments.

Sleep disruption is a common but poorly understood feature of neurodevelopmental disorders including autism spectrum disorder. A study by Bian et al. reveals that sleep disruption in adolescent mice leads to long-lasting changes in social novelty preferences. Importantly, these perturbations can be restored through balanced actions in midbrain dopamine systems.

A new ‘meta-matching’ algorithm developed by He et al., published in this issue of Nature Neuroscience, enables small MRI datasets to piggyback on larger datasets to boost prediction accuracy. This innovation may aid in efforts toward personalized psychiatry.

Degeneration of dopaminergic neurons in the substantia nigra is a pathological hallmark of Parkinson’s disease (PD). However, not all dopamine-producing neurons degenerate. Kamath, Abdulraouf et al. find that there are ten transcriptionally defined dopaminergic subpopulations in the human substantia nigra, but only one carries significant PD genetic risk and is vulnerable to neurodegeneration in PD.

Two recent papers reveal that the brain can regulate its own immune responses by sending molecular cues to immune cells in the skull bone marrow via the cerebrospinal fluid. Furthermore, experimental spinal cord injury or bacterial meningitis specifically activate local vertebral and skull-resident hematopoietic cell injury responses.

Pettit, Yuan and Harvey find that hippocampal spatial maps degrade when mice voluntarily disengage from a navigation task, even without changes in sensory or self-motion cues. This finding suggests that internal state could have an active role in supporting navigational coding and, perhaps, spatial memory.

Wang et al. used transcriptomic profiles of olfactory sensory neurons to determine the identity of their odorant receptors and map the location of their corresponding glomeruli on the olfactory bulb surface. The method enables high-throughput molecular mapping of the glomerular layout and opens up new venues to understand olfactory processing.

A study by Cook et al. shows that mice can use auditory feedback from their own actions to precisely time an interval. This feedback is processed in the secondary auditory cortex and regulates performance via a corticostriatal circuit.

As researchers uncover new roles for the microbiome in health and disease, recent studies have emerged linking the microbiome to aspects of aging. Mossad and colleagues demonstrate that a microbiome-mediated disruption of the intestinal barrier, associated with aging, can contribute to dysfunction of microglia in mice.

Complex and intelligent behavior depends not just on sensory evidence but also on internal cognitive state. Ashwood et al. use a powerful statistical method to identify hidden internal states in choice data.

Adult male rodents have long been known to show stronger hippocampal long-term potentiation (LTP) and learning than females. Le et al. find that this sex difference is reversed in pre-pubescent animals, and identify a female-specific mechanism that increases LTP threshold and decreases spatial memory in females after puberty.

The duodenum distinguishes between sugar and sweeteners, but the cells involved in this process remain elusive. Buchanan and colleagues engineered a flexible optic fiber for optogenetic manipulation of gut cells in mice. Silencing duodenal CCK cells reduced the preference for sugar over sweetener intake. Gut optogenetics may elucidate how the gut–brain axis regulates feeding and glucose homeostasis.

Yang et al. demonstrate that sensory neurons are enriched for the anthrax toxin receptor-2. Edema toxin, which acts via this receptor, induces analgesia in mice and can also be engineered to deliver large cargoes such as botulinum toxin in order to selectively silence sensory neurons.

Allen et al. introduce the Natural Scenes Dataset — high-resolution fMRI data from eight individuals scanned as they collectively viewed more than 70,000 natural images and performed a continuous recognition task. This resource promises to yield insights into visual perception and memory and to help bridge cognitive neuroscience and artificial intelligence.

Our brains are wired to steer us toward novel experiences. Ogasawara et al. define nodes in a network that underlies novelty-seeking behavior distinct from novelty-orienting responses. In this network, anterior ventral medial temporal cortex (AVMTC) mediates novelty-related sensory processing, and zona incerta uses input from AVMTC to guide gaze shifts for novelty seeking.