Volume 24 Issue 8, August 2021

Understanding how the brain makes decisions is a major area of focus in both animal and human cognitive neuroscience. Much of this work, especially in primates, has explicated the role of various cortical areas in forming decisions. In new research, perturbations of the superior colliculus by Jun et al. reveal a large and causal role in accumulating evidence for this midbrain structure classically thought of as being involved in simpler functions related to eye movement control.

Decision-making often involves temporally extended planning and information search. This Review discusses recent theoretical frameworks that have been used to study such naturalistic decision-making and its neural basis.

Hippocampal ~8-Hz theta rhythmicity is enhanced in virtual reality, seen in the local field potential, pyramidal cells and interneurons. It is accompanied by the emergence of a novel ~4-Hz eta rhythm, seen in the local field potential and interneurons.

An analysis of the largest exome sequencing dataset of people with obsessive–compulsive disorder to date (n = 1,313 affected individuals), where both case–control and de novo variant studies support a contribution of rare damaging coding variants to risk.

ALS-linked mutations in FUS trigger defects within the nucleocytoplasmic transport pathway in human neurons and Drosophila. Aberrant interactions between FUS and nucleoporins are thought to underlie these defects.

Maimon et al. demonstrate a therapeutically viable approach, single-dose injection of a DNA drug to suppress synthesis of PTB, to generate new neurons in the aged mouse hippocampus and enhance memory after their integration into endogenous circuits.

How ketamine and scopolamine produce sustained antidepressant effects remains unknown. Kim et al. show that BDNF-dependent MeCP2 phosphorylation drives sustained antidepressant effects of ketamine and scopolamine with distinct synaptic plasticity changes.

Duan et al. reveal circuit mechanisms of executive control in the midbrain superior colliculus (SC), where response inhibition and context-based vector inversion are instantiated by specific SC subpopulations.

Unilateral inactivation of the superior colliculus in monkeys reveals that a brainstem structure plays a causal role in how evidence is computed for decisions, a process usually attributed to the forebrain.

Tuberal nucleus SST⁺ neurons respond to palatable food. The activity of these SST neurons together with their plastic inputs from the ventral subiculum play critical roles in contextually conditioned feeding.

By recording from hundreds of cerebellar granule cell axons with three-dimensional two-photon calcium imaging, Lanore et al. show that population activity is high-dimensional and that quiet wakeful and active states are orthogonally arranged in neuronal activity space.

This work provides a first molecular view of dendritic spines, for both the mushroom and stubby classes, obtained by integrating electron microscopy, quantitative biochemistry, super-resolution microscopy and 3D molecular visualizations.

SPLiT-seq single-nucleus RNA sequencing of the developing human cerebellum reveals cell-type complexities and prolonged maturation compared to mouse with important disease implications.

This paper reports activation patterns for fMRI tasks assessing response inhibition, working memory and reward processing obtained at baseline in the longitudinal ABCD Study, providing a reference for research into adolescent brain development.