Reviews & Analysis

How do fundamental synaptic processes in specific neuron populations drive behavior? A new study links a reduction of tonic inhibitory GABA current in a subset of central amygdala neurons to anxiety after fear conditioning.

A new study shows that an efficient allocation of sensory resources can lead to Bayesian estimates that are biased away from the prior, accounting for effects such as the bias toward oblique angles in orientation perception.

As conversion of odor signals to a two-dimensional map of activated glomeruli in the olfactory bulb is the key to odor recognition, decoding and deorphanizing of odorant receptors in the olfactory map is of great interest. Two genome-wide techniques now offer the ability to pair any odorant with its receptors.

In this Review, Hollon, Burgeno and Phillips discuss recent studies providing mechanistic insight into how stress alters circuitry involved in reward-related learning and motivation, as well as work examining how acute and chronic stress affect action selection in both rodents and humans.

The brain perceives and adapts to stressors via multiple interacting molecular mechanisms involving the cell surface, cytoskeleton and epigenetic regulation resulting in structural remodeling, with continually changing gene expression. Understanding mechanisms of plasticity and vulnerability facilitate development of intervention for anxiety and depressive disorders as well as age-related cognitive decline.

A mechanistic understanding of anxiety is required to advance the development of next-generation therapies for anxiety disorders. In this Review, Calhoon and Tye discuss recent insights into the circuit physiology driving anxiety-like behavior gained through the application of modern approaches in neuroscience.

In their Perspective, Hariri & Holmes consider unique features of translational research on stress-related disorders that have helped fuel a productive dialogue from bench to bedside and back, as well as sparked important advances in identifying novel risk biomarkers and therapeutic strategies.

Hodes et al. discuss mounting evidence in humans and rodent models of depression that causally links increased inflammation to depression. They take the perspective that heightened inflammation is a risk factor for depression and suggest targeted therapeutics to reduce inflammation as a novel approach to antidepressant treatment.

Severe stress impairs cognitive function, but enhances emotionality. This Review describes how stress triggers contrasting patterns of plasticity in the hippocampus, prefrontal cortex and amygdala, all brain areas that are involved in learning and memory. These features of stress-induced plasticity can have long-term consequences for the debilitating symptoms of stress-related disorders.

Research has revealed the molecular events that weaken connectivity in prefrontal cortical circuits during stress exposure. These events rapidly flip the brain from a reflective to reflexive state and may also contribute to degenerative changes in schizophrenia and Alzheimer's disease. This mechanistic understanding has translated to therapeutics for prefrontal disorders.

Environmental influences affect the brain and mental health and often are social or have social components, even the more complex societal or area-level exposures. This Review discusses the neural correlates of adverse and protective social influences and argues that innovative methods may provide ecologically more valid insights in social neuroscience.

In this review, Bale and Epperson discuss the importance of sex differences in stress found at all stages of life. As stress dysregulation is the most common feature across neuropsychiatric diseases, understanding sex differences in stress pathway development and maturation may predict disease risk and resilience factors across the lifespan.

Dopamine loss in Parkinson's disease affects not only the basal ganglia, but also motor cortex, causing a surprising increase of spine turnover in the cortical dendritic tree and altering synaptic plasticity and memory retention.

Our internal states can color our memories just as powerfully as the external environment. A study finds that hippocampal GABA_A receptors and associated microRNAs are important for generating state-dependent contextual fear memories.

How do individuals attribute dispositional properties, or traits, to others? A study suggests that associative learning processes underlie aspects of trait learning at both neural and behavioral levels.

Reflexes help us maintain a default posture and direction of locomotion. But what if we deliberately want to move differently? In Drosophila, the brain modifies a visually driven stabilization reflex to enable voluntary movements.

A study finds that pain hypersensitivity in male and female mice is differentially dependent on microglia and T cells, and describes a sex-specific response to microglia-targeted pain treatments. This sex difference will be important to consider when developing treatments for pain and other neurological disorders involving microglia and immune cells.

Imaging experiments in awake mice reveal striking, circuit-specific synaptic structural remodeling of inhibitory axons during learning.

How do neurons combine distinct information streams and form long-lasting associations? Dendritic plateau potentials may allow the integration and storage of coincident location and contextual information in hippocampal neurons.