Volume 26 Issue 2, February 2023

Craving is a core characteristic of drug addiction and eating disorders. A new study identifies an fMRI-based neural signature of craving that is common to both food and drugs, predicts self-reported craving, distinguishes drug users from non-users, and tracks the efficacy of a cognitive therapy technique to reduce craving.

Single-cell genomics reveal that Alzheimer’s dementia involves the complex interplay of virtually every major brain cell type. Cell-type-specific molecular perturbations modulate signaling pathways related to lipid handling, immune signaling and metabolic reprogramming.

Sulaman et al. detail the neuronal underpinnings of sleep–wake states and discuss their intersection with hunger, fear and thermoregulatory circuits. They propose a de-arousal model for sleep initiation and highlight lingering questions in the field.

Pathological α-synuclein (α-Syn) spreading is critical for the progression of many neurodegenerative diseases. The authors demonstrate that soluble α-Syn post-translational modifications (PTMs) dramatically modulate pathological α-synuclein spreading.

MVA-CoV2-S vaccination confers full protection against SARS-CoV-2 neuroinvasion in humanized mice, preventing brain viral replication and the associated neuronal and vascular damage, even after SARS-CoV-2 reinfection.

Mice were trained to discriminate objects using their whiskers. The geometry of the neural representations recorded in somatosensory cortex was disentangled with small non-linear perturbations, allowing for generalization and flexibility.

Sounds evoke activity in visual cortex. Bimbard et al. find that this activity is stereotyped across cells, not specific to visual cortex, independent of inputs from auditory cortex and predicted by stereotyped movements elicited by the sounds.

Lee et al. show that the long-term storage of remote contextual memories involves progressive and synapse-specific strengthening of excitatory connections between memory engram neurons in the prefrontal cortex.

The authors show that action value modulates motivation to perform a decision-making task more strongly in females than in males. Anterior cingulate cortex neurons that project to the striatum contribute to this sex difference.

In bat CA1, the authors found contextual time cells encoding spatial context and time, another population purely encoding elapsed time and social time cells encoding sequences aligned to another bat’s landing in a social imitation task.

Tremblay, Testard et al. show that, in monkeys, spontaneous movements do not occlude neural coding of cognitive variables. However, movements predict upcoming decisions and partly explain neural activity, potentially confounding brain recording experiments.

What are the representations that enable diverse human cognition? The authors investigate cortical representations across 26 tasks and the conditions by which artificial neural network models reproduce these representations.

Craving—the urge to use a drug or to eat—is a core feature of substance use disorders. Koban et al. present an fMRI-based and machine-learning-based neuromarker that predicts the intensity of drug and food craving and separates drug users from non-users.

Activity in a neural population arises from both its inputs and its recurrent connections. Here the authors show that analyzing the dynamics of trial-to-trial variability in activity can offer insights into delineating these contributions.

A computational model predicts coordinated drift of neural receptive fields during noisy representation learning and recapitulates experimental observations in the posterior parietal cortex and hippocampal CA1.

The authors developed an optimized rabies tracing system for generating brain-wide monosynaptic input connectomes, and applied it in mouse visual cortex to reveal topographically organized subnetworks co-defined by visual areas, layers and cell classes.