Research articles

Using hemisphere-specific optogenetic activation of hippocampal fibers, this study finds that the magnitude of long-term potentiation in CA1 neurons depends on whether afferents originate in left or right CA3.

This study shows that lesioning a rat's amygdala affects only familiarity-based recognition, having no effect on recollection-based recognition, and further dissociates the role of medial temporal lobe structures mediating recognition memory.

One mechanism by which medial prefontal cortex (mPFC) exerts cognitive control is thought to involve the subthalamic nucleus (STN), which acts as a temporary brake on behavior. Here the authors found increases in mPFC and STN theta power as a function of decision conflict. Increases in mPFC theta power predicted increased decision thresholds. STN deep brain stimulation reversed this relationship, resulting in impulsive choice.

Inserting a recording electrode into the nostrils of human volunteers allowed the authors to record neural activity directly from the olfactory epithelium, and measures of olfactory perception, all from the same individuals. This uncovered a non-uniform patchy organization of the receptive surface, which was organized in part according to the perception of odorant pleasantness.

The authors report the existence of a bilateral parieto-frontal network in humans whose hemispheric lateralization predicts the degree of specialization of the right hemisphere for visuospatial attention. This specialization is associated with an unbalanced speed of visuospatial processing between the two hemispheres.

Using direct recordings in monkeys, the authors find that attention spreads to elements when gestalt cues indicate that it is part of an attended object, even when these elements themselves are outside of the focus of attention. This finding supports object-based attentional theories.

The authors present a computational model based on standard learning rules that can simulate and account for a large range of known effects in the medial prefrontal cortex (mPFC), including dorsal anterior cingulate cortex (dACC). Their model suggests that this region is involved in learning and predicting the likely outcomes of actions and detecting when those predicted outcomes fail to occur.

Recording from primate retinal ganglion cells, the authors find that cone noise, traversing the retina through diverse pathways, accounts for most of the noise and correlations in the retinal output. This constrains how higher centers exploit signals carried by parallel visual pathways.

The authors employ the computational learning approach that is widely used in the striatum to examine the contributions of the amygdala, and find that these two structures have complementary roles in aversive learning.

Mammalian grid cells have a spatially periodic pattern of responses to location, which is a puzzling feature. Here, the authors demonstrate that this pattern of activity is compatible with a coding scheme that allows for very accurate localization.

The authors show that retrieval of fear memory modifies the membrane expression of GluA2-containing AMPA receptors and synaptic strength in the dorsal hippocampus. This synaptic plasticity exerts an inhibitory constraint on memory strengthening and underlies the loss of fear response by reinterpretation of memory content during adaptive reconsolidation.

The authors characterize the endogenous local calcium dynamics in the processes of adult mouse hippocampal astrocytes, and find that the astrocytic Ca²⁺ activity is generated by synaptic events and contributes to basal synaptic transmission reliability.

Adaptation helps sensory neurons optimize in a steady environment, but can cause a failure in transmission when the environment changes suddenly. The authors report that the retina overcomes this limitation by complementing adaptation with an opposing process that sensitizes a separate population of neurons following a strong stimulus.

The authors determine the crystal structure of the extracellular domain of a receptor chimera constructed from the human α₇ acetylcholine receptor (AChR) and acetylcholine binding protein (AChBP), as well as the structure with bound epibatidine, a potent AChR agonist. The structures provide a realistic template for structure-aided drug design and for defining structure-function relationships of α₇ AChRs.

CREB-mediated transcription is known to be important for ocular dominance plasticity (ODP). Expression of the mircoRNA miR-132 is under CREB control, and this study finds that miR-132 directly regulates ODP.

This study identifies a subset of microRNAs whose expression is differentially regulated by visual experience and finds that inhibition of one of the miRNAs, miR-132, in the mouse visual cortex impairs ocular dominance plasticity.

The authors use multivoxel pattern analysis of fMRI data to examine the role of lateral occipital (LO) cortex in the recognition of real-world visual scenes. They find that LO may support an object-based channel for scene recognition by combining information about multiple objects within a scene.

Homeobox proteins Engrailed-1 (En1) and Engrailed-2 (En2) are transcription factors that direct midbrain cell specification during development. Here, the authors show that exogenous En1 and En2 protect against dopaminergic cell death in several rodent models of Parkinson's disease.

The authors describe a chemical approach for imaging deep into fixed brain tissue using Scale, a solution that renders biological samples transparent, but preserves fluorescent signals. This technique allows for imaging at unprecedented depth and at subcellular resolution, and makes three-dimensional reconstruction of neural networks possible without serial sectioning.

Recording from neurosurgical patients undergoing epilepsy monitoring, the authors find specific responses to pictures of animals in the right amygdala.