Volume 26 Issue 4, April 2023

In the brains of patients with epilepsy, apolipoprotein E-mediated lipid transfer from hyperactive neurons to astrocytes results in lipid metabolism reprogramming and formation of lipid-accumulated reactive astrocytes. These astrocytes exacerbate abnormal discharges of neighboring neurons and, in mice, aggravate seizure symptoms, leading to disease progression.

This study mapped the developmental trajectory of transmission speed in the human brain by using electrical pulses and intracranial recordings. The authors found that these pulses travel with increasing speeds up to at least the age of 30.

Chen et al. describe a new subtype of reactive astrocyte formed by APOE-mediated lipid accumulation in individuals with epilepsy and mouse models. These reactive astrocytes aggravate seizure symptoms and could serve as new therapeutic targets for epilepsy.

The mechanisms of remyelination are unclear. Here, the authors develop and use two-photon apoptotic targeted ablation and show a form of rapid synchronous remyelination mediated by a distinct subset of OPCs that can occur in adult mice but not in aging.

The authors find that 40-Hz flickering light does not suppress Aβ, activate microglia or engage native gamma oscillations. Thus, visual flicker stimulation may not be a viable mechanism for altering AD pathology and modulating deep structures.

The authors show that norepinephrine signaling to astrocytes in the mouse visual cortex acts as a separate neuromodulatory pathway that regulates the effects of arousal on neuronal activity and cortical state.

The caudal ventrolateral medulla was thought to be involved in pain control, but its pathway was unknown. Here, Gu et al. identify the molecular components of a caudal ventrolateral medulla–locus coeruleus–spinal cord pathway and show it has a role in counter-stimulus pain control.

The statistics of natural scenes are not uniform—their structure varies dramatically from ground to sky. A combination of theory and experiments revealed that the visual system has adapted to these inhomogeneities to increase coding efficiency.

The authors find that the hippocampus creates a spatial and predictive cognitive map, and show how orbitofrontal and hippocampal computations select these maps adaptively to guide novel choices.

During planning, the brain rapidly activates memories of paths leading to reward or punishment. In a new MEG study, the authors show that choosing to approach under uncertainty evokes reactivation of potential punishment, while avoiding reactivates forgone rewards.

Sydnor et al. provide evidence that human neurodevelopment unfolds along a hierarchical cortical axis from childhood to adolescence and demonstrate how environmental influences on the maturing brain are shaped by this developmental program.

Buch et al. used machine learning to identify brain–behavior dimensions that define four robust ASD subtypes linked to distinct molecular pathways and that suggest personalized therapeutic targets for circuit-based neuromodulation and pharmacotherapy.

The authors compare three classes of models—acoustic, semantic and sound-to-event deep neural network—to determine which can best link specific features of auditory stimuli to predicted functional magnetic resonance imaging responses in auditory cortical regions.

The authors pooled resources to identify best practices and develop a new standardized protocol for estimating functional connectivity in rats with magnetic resonance imaging.

Knowing one’s own behavioral state is important to contextualize sensory cues and identify appropriate future actions. Here the authors show how neurons ascending from the fly motor system convey behavioral state signals to specific brain regions.

The authors developed flexible, unfolded mesh electronics for implantation in multiple brain regions of mice. The probes show minimal immune response and electrode drift, enabling stable recording of single-unit action potentials from the same neurons during the adult life of animals.