How Outcome Uncertainty Mediates Attention, Learning, and Decision-Making.
Abstract Animals and humans evolved sophisticated nervous systems that endowed them with the ability to form internal-models or beliefs and make predictions about the future to survive and flourish in a world in which future outcomes are often uncertain. Crucial to this capacity is the ability to adjust behavioral and learning policies in response to the level of uncertainty. Until recently, the neuronal mechanisms that could underlie such uncertainty-guided control have been largely unknown. In this review, I discuss newly discovered neuronal circuits in primates that represent uncertainty about future rewards an...
Source: Trends in Neurosciences - July 28, 2020 Category: Neuroscience Authors: Monosov IE Tags: Trends Neurosci Source Type: research

A Multi-Brain Framework for Social Interaction.
We describe key findings from multi-brain experiments in humans and animal models that shed new light on the function of social circuits in health and disease. Finally, we discuss recent progress in elucidating the cellular-level mechanisms underlying inter-brain neural dynamics and outline key areas for future research. PMID: 32709376 [PubMed - as supplied by publisher] (Source: Trends in Neurosciences)
Source: Trends in Neurosciences - July 22, 2020 Category: Neuroscience Authors: Kingsbury L, Hong W Tags: Trends Neurosci Source Type: research

Tapping into Multi-Faceted Human Behavior and Psychopathology Using fMRI Brain Dynamics.
Abstract Human behavior comprises many aspects that stand out by their dynamic nature. To quantify its neural underpinnings, time-resolved fMRI methods have blossomed over the past decade. In this review we conceptually organize a broad repertoire of dynamic analytical pipelines and extract general observations on their application to the study of behavior and brain disorders. We aim to provide an extensive overview instead of examining only selected methodological families or specific behavioral domains. We consider behavioral aspects with distinct long-term stability (e.g., physiological state versus personality...
Source: Trends in Neurosciences - July 15, 2020 Category: Neuroscience Authors: Bolton TAW, Morgenroth E, Preti MG, Van De Ville D Tags: Trends Neurosci Source Type: research

The Paradox of HIV Blood-Brain Barrier Penetrance and Antiretroviral Drug Delivery Deficiencies.
Abstract HIV attacks the body's immune cells, frequently compromises the integrity of the blood-brain barrier (BBB), and infects the CNS in the early stages of infection. Dysfunction of the BBB further potentiates viral replication within the CNS, which can lead to HIV-associated neuropathology. Antiretroviral therapy (ART) significantly improves HIV patient outcomes and reduces mortality rates. However, there has been limited progress in targeting latent viral reservoirs within the CNS, which may eventually lead to rebound viremia. While ART drugs are shown to be effective in attenuating HIV replication in the pe...
Source: Trends in Neurosciences - July 15, 2020 Category: Neuroscience Authors: Osborne O, Peyravian N, Nair M, Daunert S, Toborek M Tags: Trends Neurosci Source Type: research

The Gut-CNS Axis in Multiple Sclerosis.
Abstract Multiple sclerosis (MS) is an autoimmune inflammatory disease of the CNS driven by the inflammatory activity of peripheral immune cells recruited to the CNS and by CNS-resident glial cells. MS pathogenesis has been linked to both genetic and environmental factors. In addition, the commensal flora have been shown to modulate immune processes relevant to MS pathogenesis. We discuss the effects of the gut microbiota on T cells and glial cells, and their relevance for the control of inflammation and neurodegeneration in MS. A better understanding of the gut-CNS axis will shed new light on the mechanisms of di...
Source: Trends in Neurosciences - July 7, 2020 Category: Neuroscience Authors: Kadowaki A, Quintana FJ Tags: Trends Neurosci Source Type: research

The Role of Astrocytes in Remyelination.
Abstract Remyelination is the regeneration of myelin sheaths following demyelination. This regenerative process is critical for the re-establishment of axonal conduction velocity and metabolic support to the axons. Successful remyelination in the CNS generally depends on the activation, proliferation, and differentiation of oligodendrocyte progenitor cells (OPCs). However, other cell types play critical roles in establishing where a lesion is conducive for regeneration. In the last few years, several studies have described beneficial and detrimental roles played by astrocytes in remyelination. This review will dis...
Source: Trends in Neurosciences - July 1, 2020 Category: Neuroscience Authors: Rawji KS, Gonzalez Martinez GA, Sharma A, Franklin RJM Tags: Trends Neurosci Source Type: research

An Emerging Role for Prolactin in Female-Selective Pain.
Abstract Women experience many pain conditions more frequently when compared with men, but the biological mechanisms underlying sex differences in pain remain poorly understood. In particular, little is known about possible sex differences in peripheral nociceptors, the fundamental building blocks of pain transmission. Emerging evidence reveals that prolactin (PRL) signaling at its cognate prolactin receptor (PRLR) in primary afferents promotes nociceptor sensitization and pain in a female-selective fashion. In this review, we summarize recent progress in understanding the female-selective role of PRL/PRLR in noci...
Source: Trends in Neurosciences - June 30, 2020 Category: Neuroscience Authors: Chen Y, Navratilova E, Dodick DW, Porreca F Tags: Trends Neurosci Source Type: research

Islands of Awareness or Cortical Complexity?
PMID: 32622543 [PubMed - as supplied by publisher] (Source: Trends in Neurosciences)
Source: Trends in Neurosciences - June 27, 2020 Category: Neuroscience Authors: Cecconi B, Laureys S, Annen J Tags: Trends Neurosci Source Type: research

From Complexity to Consciousness.
PMID: 32622544 [PubMed - as supplied by publisher] (Source: Trends in Neurosciences)
Source: Trends in Neurosciences - June 24, 2020 Category: Neuroscience Authors: Bayne T, Seth AK, Massimini M Tags: Trends Neurosci Source Type: research

Do Nicotinic Receptors Modulate High-Order Cognitive Processing?
Abstract Recent studies provided strong evidence that deficits in cholinergic signaling cause disorders of cognition and affect conscious processing. Technical advances that combine molecular approaches, in vivo recordings in awake behaving animals, human brain imaging, and genetics have strengthened our understanding of the roles of nicotinic acetylcholine receptors (nAChRs) in the modulation of cognitive behavior and network dynamics. Here, we review the emergent role of nAChRs in high-order cognitive processes and discuss recent work implicating cholinergic circuits in cognitive control, including conscious pro...
Source: Trends in Neurosciences - June 23, 2020 Category: Neuroscience Authors: Koukouli F, Changeux JP Tags: Trends Neurosci Source Type: research

Movement-Related Signals in Sensory Areas: Roles in Natural Behavior.
Abstract Recent studies have demonstrated prominent and widespread movement-related signals in the brain of head-fixed mice, even in primary sensory areas. However, it is still unknown what role these signals play in sensory processing. Why are these sensory areas 'contaminated' by movement signals? During natural behavior, animals actively acquire sensory information as they move through the environment and use this information to guide ongoing actions. In this context, movement-related signals could allow sensory systems to predict self-induced sensory changes and extract additional information about the environ...
Source: Trends in Neurosciences - June 22, 2020 Category: Neuroscience Authors: Parker PRL, Brown MA, Smear MC, Niell CM Tags: Trends Neurosci Source Type: research

Shedding Light on Chandelier Cell Development, Connectivity, and Contribution to Neural Disorders.
Abstract Chandelier cells (ChCs) are a unique type of GABAergic interneuron that selectively innervate the axon initial segment (AIS) of excitatory pyramidal neurons; the subcellular domain where action potentials are initiated. The proper genesis and maturation of ChCs is critical for regulating neural ensemble firing in the neocortex throughout development and adulthood. Recently, genetic and molecular studies have shed new light on the complex innerworkings of ChCs in health and disease. This review presents an overview of recent studies on the developmental origins, migratory properties, and morphology of ChCs...
Source: Trends in Neurosciences - June 16, 2020 Category: Neuroscience Authors: Gallo NB, Paul A, Van Aelst L Tags: Trends Neurosci Source Type: research

Local Sourcing of Secretory Proteins in Faraway Places.
Abstract A recent paper by Carter et al. identifies a novel organelle, the ribosome-associated vesicle (RAV), that might serve as a portable, local factory for producing proteins destined for the secretory pathway. The appearance of RAVs in dendrites suggests they may serve to generate membrane and secreted proteins in distal processes. PMID: 32546404 [PubMed - as supplied by publisher] (Source: Trends in Neurosciences)
Source: Trends in Neurosciences - June 13, 2020 Category: Neuroscience Authors: Farrell RJ, Ryan TA Tags: Trends Neurosci Source Type: research

Neurodevelopmental Disorders: From Genetics to Functional Pathways.
Abstract Neurodevelopmental disorders (NDDs) are a class of disorders affecting brain development and function and are characterized by wide genetic and clinical variability. In this review, we discuss the multiple factors that influence the clinical presentation of NDDs, with particular attention to gene vulnerability, mutational load, and the two-hit model. Despite the complex architecture of mutational events associated with NDDs, the various proteins involved appear to converge on common pathways, such as synaptic plasticity/function, chromatin remodelers and the mammalian target of rapamycin (mTOR) pathway. A...
Source: Trends in Neurosciences - June 4, 2020 Category: Neuroscience Authors: Parenti I, Rabaneda LG, Schoen H, Novarino G Tags: Trends Neurosci Source Type: research

The Evolution-Driven Signature of Parkinson's Disease.
Abstract In this review, we approach Parkinson's disease (PD) in the context of an evolutionary mismatch of central nervous system functions. The neurons at risk have hyperbranched axons, extensive transmitter release sites, display spontaneous spiking, and elevated mitochondrial stress. They function in networks largely unchanged throughout vertebrate evolution, but now connecting to the expanded human cortex. Their breakdown is favoured by longevity. At the cellular level, mitochondrial dysfunction starts at the synapses, then involves axons and cell bodies. At the behavioural level, network dysfunctions provoke...
Source: Trends in Neurosciences - June 1, 2020 Category: Neuroscience Authors: Diederich NJ, Uchihara T, Grillner S, Goetz CG Tags: Trends Neurosci Source Type: research

Neuronal Maturation: Challenges and Opportunities in a Nascent Field.
Abstract After its initial development, the nervous system matures to connect and shape the neuronal circuitry and to keep it functional in humans for decades. Here we conceptualize neuronal maturation as a research field that will have, we would argue, a strong impact on understanding the healthy and diseased nervous system. Identifying the key mechanisms underlying neuronal maturation has the potential to reverse this process in adulthood, thereby facilitating regeneration. PMID: 32459989 [PubMed - in process] (Source: Trends in Neurosciences)
Source: Trends in Neurosciences - May 29, 2020 Category: Neuroscience Authors: Bradke F, Di Giovanni S, Fawcett J Tags: Trends Neurosci Source Type: research

Noisy Synaptic Conductance: Bug or a Feature?
Abstract More often than not, action potentials fail to trigger neurotransmitter release. And even when neurotransmitter is released, the resulting change in synaptic conductance is highly variable. Given the energetic cost of generating and propagating action potentials, and the importance of information transmission across synapses, this seems both wasteful and inefficient. However, synaptic noise arising from variable transmission can improve, in certain restricted conditions, information transmission. Under broader conditions, it can improve information transmission per release, a quantity that is relevant giv...
Source: Trends in Neurosciences - May 29, 2020 Category: Neuroscience Authors: Rusakov DA, Savtchenko LP, Latham PE Tags: Trends Neurosci Source Type: research

Impacts of Sleep Loss versus Waking Experience on Brain Plasticity: Parallel or Orthogonal?
Abstract Recent studies on the effects of sleep deprivation on synaptic plasticity have yielded discrepant results. Sleep deprivation studies using novelty exposure as a means to keep animals awake suggests that sleep (compared with wake) leads to widespread reductions in net synaptic strength. By contrast, sleep deprivation studies using approaches avoiding novelty-induced arousal (i.e., gentle handling) suggest that sleep can promote synaptic growth and strengthening. How can these discrepant findings be reconciled? Here, we discuss how varying methodologies for the experimental disruption of sleep (with differe...
Source: Trends in Neurosciences - May 29, 2020 Category: Neuroscience Authors: Havekes R, Aton SJ Tags: Trends Neurosci Source Type: research

Glucocorticoids as Mediators of Adverse Outcomes of Prenatal Stress.
Abstract A number of prenatal experiences are associated with adverse outcomes after birth, ranging from cardiovascular problems to psychiatric disease. Prenatal stress is associated with neurodevelopmental alterations that persist after birth and manifest at the behavioral level, for example, increased fearfulness, and at the physiological one, that is, brain structural and functional changes. Understanding the mechanisms that drive these lasting effects may help in preventing long-term negative outcomes of prenatal stress. Elevated glucocorticoid signaling in utero may be one of the key mediators of prenatal str...
Source: Trends in Neurosciences - May 29, 2020 Category: Neuroscience Authors: Krontira AC, Cruceanu C, Binder EB Tags: Trends Neurosci Source Type: research

Post-translational Modifications of Opioid Receptors.
Abstract Post-translational modifications (PTMs) are key events in signal transduction since they affect protein function by regulating their abundance and/or activity. PTMs involve the covalent attachment of functional groups to specific amino acids. Since they tend to be generally reversible, PTMs serve as regulators of signal transduction pathways. G-protein-coupled receptors (GPCRs) are major signaling proteins that undergo multiple types of PTMs. In this Review, we focus on the opioid receptors, members of GPCR family A, and highlight recent advances in the field that have underscored the importance of PTMs i...
Source: Trends in Neurosciences - May 29, 2020 Category: Neuroscience Authors: Lemos Duarte M, Devi LA Tags: Trends Neurosci Source Type: research

Microglia versus Monocytes: Distinct Roles in Degenerative Diseases of the Retina.
Abstract Unlike in the healthy mammalian retina, macrophages in retinal degenerative states are not solely comprised of microglia but may include monocyte-derived recruits. Recent studies have applied transgenics, lineage-tracing, and transcriptomics to help decipher the distinct roles of these two cell types in the diseasesettings of inherited retinal degenerations and age-related macular degeneration.Literature discussed here focuses on the ectopic presence of both macrophage types in the extracellular site surrounding the outer aspect ofphotoreceptor cells (i.e.,the subretinal space), which is crucially involve...
Source: Trends in Neurosciences - May 29, 2020 Category: Neuroscience Authors: Yu C, Roubeix C, Sennlaub F, Saban DR Tags: Trends Neurosci Source Type: research

Resurrecting the Mysteries of Big Tau.
Abstract Tau, a microtubule-associated protein that modifies the dynamic properties and organization of microtubules in neurons and affects axonal transport, shows remarkable heterogeneity, with multiple isoforms (45-65 kDa) generated by alternative splicing. A high-molecular-weight (HMW) isoform (110 kDa) that contains an additional large exon termed 4a was discovered more than 25 years ago. This isoform, called Big tau, is expressed mainly in the adult peripheral nervous system (PNS), but also in adult neurons of the central nervous system (CNS) that extend processes into the periphery. Surprisingly little has b...
Source: Trends in Neurosciences - May 17, 2020 Category: Neuroscience Authors: Fischer I, Baas PW Tags: Trends Neurosci Source Type: research

Closing in on Mechanisms of Open Neural Tube Defects.
Abstract Neural tube defects (NTDs) represent a failure of the neural plate to complete the developmental transition to a neural tube. NTDs are the most common birth anomaly of the CNS. Following mandatory folic acid fortification of dietary grains, a dramatic reduction in the incidence of NTDs was observed in areas where the policy was implemented, yet the genetic drivers of NTDs in humans, and the mechanisms by which folic acid prevents disease, remain disputed. Here, we discuss current understanding of human NTD genetics, recent advances regarding potential mechanisms by which folic acid might modify risk throu...
Source: Trends in Neurosciences - May 15, 2020 Category: Neuroscience Authors: Lee S, Gleeson JG Tags: Trends Neurosci Source Type: research

The Brain's Glymphatic System: Current Controversies.
Abstract The glymphatic concept along with the discovery of meningeal lymphatic vessels have, in recent years, highlighted that fluid is directionally transported within the central nervous system (CNS). Imaging studies, as well as manipulations of fluid transport, point to a key role of the glymphatic-lymphatic system in clearance of amyloid-β and other proteins. As such, the glymphatic-lymphatic system represents a new target in combating neurodegenerative diseases. Not unexpectedly, introduction of a new plumbing system in the brain has stirred controversies. This opinion article will highlight what we kno...
Source: Trends in Neurosciences - May 15, 2020 Category: Neuroscience Authors: Mestre H, Mori Y, Nedergaard M Tags: Trends Neurosci Source Type: research

Anterior to Posterior Whole-Brain Gradient for Different Types of Memories?
Abstract Memories are consolidated from hippocampus to cortex, and recent evidence points to an anterior-posterior/ventral-dorsal gradient (in humans/rodents, respectively) across the brain that may be specialized for different types of memories. In a recent article, Cowan et al. provided evidence for this functional difference and gradient, which is also associated with sleep spindles. PMID: 32409016 [PubMed - as supplied by publisher] (Source: Trends in Neurosciences)
Source: Trends in Neurosciences - May 11, 2020 Category: Neuroscience Authors: Navarro-Lobato I, Genzel L Tags: Trends Neurosci Source Type: research

Effects of Exercise on Brain and Cognition Across Age Groups and Health States.
Abstract Exercise has been shown to benefit brain structure and function, particularly in aging populations. However, the mechanisms by which exercise exerts its effects, especially in humans, are not fully understood. This review argues that one reason for this knowledge gap is that exercise likely operates through multiple levels of mechanisms. Furthermore, the mechanisms of exercise may vary depending on factors such as age and health state. We discuss the state of evidence at each of three levels of analysis (molecular/cellular, brain structure/function, and mental states and higher-order behaviors) and highli...
Source: Trends in Neurosciences - May 11, 2020 Category: Neuroscience Authors: Stillman CM, Esteban-Cornejo I, Brown B, Bender CM, Erickson KI Tags: Trends Neurosci Source Type: research

Network Dynamics Governed by Lyapunov Functions: From Memory to Classification.
Abstract In 1982, John Hopfield published a neural network model for memory retrieval, a model that became a cornerstone in theoretical neuroscience. In a recent paper, Krotov and Hopfield built on these early studies and showed how a network that incorporates a biologically plausible learning rule governed by a Lyapunov function can effectively perform classification tasks. PMID: 32386741 [PubMed - as supplied by publisher] (Source: Trends in Neurosciences)
Source: Trends in Neurosciences - May 5, 2020 Category: Neuroscience Authors: Stern M, Shea-Brown E Tags: Trends Neurosci Source Type: research

Connecting Pathological Cellular Mechanisms to Large-Scale Seizure Structures.
Abstract Epilepsy is a neurological disorder characterized by recurrent seizures, where abnormal electrical activity begins in a local brain area and propagates before terminating. In a recent study, Liou and colleagues used multiscale computational modeling to gain mechanistic insights into clinical seizure dynamics based on cellular-level biophysical properties. PMID: 32376035 [PubMed - as supplied by publisher] (Source: Trends in Neurosciences)
Source: Trends in Neurosciences - May 3, 2020 Category: Neuroscience Authors: Nguyen QA, Moolchand P, Soltesz I Tags: Trends Neurosci Source Type: research

Spikes to Pixels: Camera Chips for Large-scale Electrophysiology.
Abstract Implanted neural probes are among the most important techniques in both fundamental and clinical neuroscience. Despite great successes and promise, neural electrodes are technically limited by their scalability. A recent study by Obaid et al. demonstrated an innovative way to greatly scale up the channel count and density of neural electrode arrays. PMID: 32353330 [PubMed - in process] (Source: Trends in Neurosciences)
Source: Trends in Neurosciences - May 1, 2020 Category: Neuroscience Authors: Lycke R, Sun L, Luan L, Xie C Tags: Trends Neurosci Source Type: research

Narratives for Neuroscience.
Abstract People organize and convey their thoughts according to narratives. However, neuroscientists are often reluctant to incorporate narrative stimuli into their experiments. We argue that narratives deserve wider adoption in human neuroscience because they tap into the brain's native machinery for representing the world and provide rich variability for testing hypotheses. PMID: 32353331 [PubMed - in process] (Source: Trends in Neurosciences)
Source: Trends in Neurosciences - May 1, 2020 Category: Neuroscience Authors: Willems RM, Nastase SA, Milivojevic B Tags: Trends Neurosci Source Type: research

Proteome Homeostasis Dysfunction: A Unifying Principle in ALS Pathogenesis.
We present a hypothesis that proposes all genetic lesions associated with ALS (including in mRNA-binding proteins) cause widespread imbalance to an already metastable proteome. The impact of such dysfunction is felt across the entire proteome and is not restricted to a small subset of proteins. Proteome imbalance may cause functional defects, such as excitability alterations, and eventually cell death. While this idea is a unifying principle for all of ALS, we propose that stratification will appear that might dictate the efficacy of therapeutics based on the proteostasis network. PMID: 32353332 [PubMed - in process] ...
Source: Trends in Neurosciences - May 1, 2020 Category: Neuroscience Authors: Yerbury JJ, Farrawell NE, McAlary L Tags: Trends Neurosci Source Type: research

Where is Cingulate Cortex? A Cross-Species View.
Abstract To compare findings across species, neuroscience relies on cross-species homologies, particularly in terms of brain areas. For cingulate cortex, a structure implicated in behavioural adaptation and control, a homologous definition across mammals is available - but currently not employed by most rodent researchers. The standard partitioning of rodent cingulate cortex is inconsistent with that in any other model species, including humans. Reviewing the existing literature, we show that the homologous definition better aligns results of rodent studies with those of other species, and reveals a clearer struct...
Source: Trends in Neurosciences - May 1, 2020 Category: Neuroscience Authors: van Heukelum S, Mars RB, Guthrie M, Buitelaar JK, Beckmann CF, Tiesinga PHE, Vogt BA, Glennon JC, Havenith MN Tags: Trends Neurosci Source Type: research

Synthesizing Views to Understand Sex Differences in Response to Early Life Adversity.
Abstract Sex as a biological variable (SABV) is critical for understanding the broad range of physiological, neurobiological, and behavioral consequences of early life adversity(ELA). The study of the interaction of SABV and ELA ties into several current debates, including the importance of taking into account SABV in research, differing strategies employed by males and females in response to adversity, and the possible evolutionary and developmental mechanisms of altered development in response to adversity. This review highlights the importance of studying both sexes, of understanding sex differences (and simila...
Source: Trends in Neurosciences - May 1, 2020 Category: Neuroscience Authors: Bath KG Tags: Trends Neurosci Source Type: research

Getting in Touch with Mechanical Pain Mechanisms.
Abstract The peripheral somatosensory system bestows mammals with a diverse repertoire of sensory modalities: gentle touch, mechanical pain, itch, thermosensation, and proprioception. The cells and molecules that transduce many of these stimuli have already been characterized. But how somatosensory neurons transduce acutely painful mechanical forces is largely unknown and remains one of the 'final frontiers' of sensory neurobiology. In an effort to fill this gap in knowledge, recent studies have identified subpopulations of mechanical pain neurons and uncovered novel modulators of mechanical pain. These studies ha...
Source: Trends in Neurosciences - May 1, 2020 Category: Neuroscience Authors: Hill RZ, Bautista DM Tags: Trends Neurosci Source Type: research

Prenatal Origins of ASD: The When, What, and How of ASD Development.
Abstract Autism spectrum disorder (ASD) is a largely heritable, multistage prenatal disorder that impacts a child's ability to perceive and react to social information. Most ASD risk genes are expressed prenatally in many ASD-relevant brain regions and fall into two categories: broadly expressed regulatory genes that are expressed in the brain and other organs, and brain-specific genes. In trimesters one to three (Epoch-1), one set of broadly expressed (the majority) and brain-specific risk genes disrupts cell proliferation, neurogenesis, migration, and cell fate, while in trimester three and early postnatally (Ep...
Source: Trends in Neurosciences - May 1, 2020 Category: Neuroscience Authors: Courchesne E, Gazestani VH, Lewis NE Tags: Trends Neurosci Source Type: research

Imaging Brain Metabolism Using Hyperpolarized 13C Magnetic Resonance Spectroscopy.
Abstract Aberrant metabolism is a key factor in many neurological disorders. The ability to measure such metabolic impairment could lead to improved detection of disease progression, and development and monitoring of new therapeutic approaches. Hyperpolarized 13C magnetic resonance spectroscopy (MRS) is a developing imaging technique that enables non-invasive measurement of enzymatic activity in real time in living organisms. Primarily applied in the fields of cancer and cardiac disease so far, this metabolic imaging method has recently been used to investigate neurological disorders. In this review, we summarize ...
Source: Trends in Neurosciences - May 1, 2020 Category: Neuroscience Authors: Le Page LM, Guglielmetti C, Taglang C, Chaumeil MM Tags: Trends Neurosci Source Type: research

White Matter Microstructure across the Psychosis Spectrum.
Abstract Diffusion-weighted imaging (DWI) is a neuroimaging technique that has allowed us an unprecedented look at the role that white matter microstructure may play in mental illnesses, such as psychosis. Psychosis-related illnesses, including schizophrenia, are increasingly viewed as existing along a spectrum; spectrums may be defined based on factors such as stage of illness, symptom severity, or genetic liability. This review first focuses on an overview of some of the recent findings from DWI studies. Then, it examines the ways in which DWI analyses have been extended across the broader psychosis spectrum, or...
Source: Trends in Neurosciences - April 26, 2020 Category: Neuroscience Authors: Karlsgodt KH Tags: Trends Neurosci Source Type: research

Contextual Codes in the Hippocampus.
This study demonstrates how a hippocampal cognitive map can flexibly reflect both spatial and nonspatial task demands. PMID: 32340746 [PubMed - as supplied by publisher] (Source: Trends in Neurosciences)
Source: Trends in Neurosciences - April 24, 2020 Category: Neuroscience Authors: Geva-Sagiv M, Ranganath C Tags: Trends Neurosci Source Type: research

Calming Neurons with a Microglial Touch.
Abstract In vivo two-photon imaging of microglia in the intact brain has revealed that microglia constantly survey neuronal soma. Research over the past decade and a recent paper by Cserép et al. published in Science are now uncovering the nature, mechanisms, and consequences of these interactions in health and injury. PMID: 32209451 [PubMed - in process] (Source: Trends in Neurosciences)
Source: Trends in Neurosciences - March 28, 2020 Category: Neuroscience Authors: Sharma K, Wu LJ, Eyo UB Tags: Trends Neurosci Source Type: research

How Early Life Adversity Influences Defensive Circuitry.
Abstract Childhood maltreatment increases the likelihood of developing anxiety disorders in humans. Early life adversity (ELA) paradigms in rodents produce lasting increases in avoidant and inhibitory responses to both immediate and nonspecific threats, collectively referred to as defensive behaviors. This approach provides an opportunity to thoroughly investigate the underlying mechanisms, an effort that is currently under way. In this review, we consider the growing literature indicating that ELA alters the rhythmic firing of neurons in brain regions associated with defensive behavior, as well as potential neuro...
Source: Trends in Neurosciences - March 28, 2020 Category: Neuroscience Authors: Murthy S, Gould E Tags: Trends Neurosci Source Type: research

Quiescent Neural Stem Cells for Brain Repair and Regeneration: Lessons from Model Systems.
Abstract Neural stem cells (NSCs) are multipotent progenitors that are responsible for producing all of the neurons and macroglia in the nervous system. In adult mammals, NSCs reside predominantly in a mitotically dormant, quiescent state, but they can proliferate in response to environmental inputs such as feeding or exercise. It is hoped that quiescent NSCs could be activated therapeutically to contribute towards repair in humans. This will require an understanding of quiescent NSC heterogeneities and regulation during normal physiology and following brain injury. Non-mammalian vertebrates (zebrafish and salaman...
Source: Trends in Neurosciences - March 28, 2020 Category: Neuroscience Authors: Otsuki L, Brand AH Tags: Trends Neurosci Source Type: research

Resolving the Synaptic versus Developmental Dichotomy of Autism Risk Genes.
Abstract Genes that are mutated in Autism Spectrum Disorders (ASD) can be classified broadly as either synaptic or developmental. But what if this is a false distinction? A recent spate of publications has provided evidence for developmental mechanisms that rely on neural activity for proper cortical development. Conversely, a growing body of evidence indicates a role for developmental mechanisms, particularly chromatin remodeling, during learning or in response to neural activity. Here, we review these recent publications and propose a model in which genes that confer ASD risk operate in signal transduction netwo...
Source: Trends in Neurosciences - March 28, 2020 Category: Neuroscience Authors: Heavner WE, Smith SEP Tags: Trends Neurosci Source Type: research

The Age-Dependent Neural Substrates of Blindsight.
Abstract Some patients who are considered cortically blind due to the loss of their primary visual cortex (V1) show a remarkable ability to act upon or discriminate between visual stimuli presented to their blind field, without any awareness of those stimuli. This phenomenon is often referred to as blindsight. Despite the range of spared visual abilities, the identification of the pathways mediating blindsight remains an active and contentious topic in the field. In this review, we discuss recent findings of the candidate pathways and their relative contributions to different forms of blindsight across the lifespa...
Source: Trends in Neurosciences - March 28, 2020 Category: Neuroscience Authors: Fox DM, Goodale MA, Bourne JA Tags: Trends Neurosci Source Type: research

Neurodevelopmental Outcomes of Prenatal Preeclampsia Exposure.
Abstract Preeclampsia is a dangerous hypertensive disorder of pregnancy with known links to negative child health outcomes. Here, we review epidemiological and basic neuroscience work from the past several decades linking prenatal preeclampsia to altered neurodevelopment. This work demonstrates increased rates of neuropsychiatric disorders [e.g., increased autism spectrum disorder, attention deficit hyperactivity disorder (ADHD)] in children of preeclamptic pregnancies, as well as increased rates of cognitive impairments [e.g., decreased intelligence quotient (IQ), academic performance] and neurological disease (e...
Source: Trends in Neurosciences - March 28, 2020 Category: Neuroscience Authors: Gumusoglu SB, Chilukuri ASS, Santillan DA, Santillan MK, Stevens HE Tags: Trends Neurosci Source Type: research

Early Adversity and Critical Periods: Neurodevelopmental Consequences of Violating the Expectable Environment.
Abstract It is now widely recognized that children exposed to adverse life events in the first years of life are at increased risk for a variety of neural, behavioral, and psychological sequelae. As we discuss in this paper, adverse events represent a violation of the expectable environment. If such violations occur during a critical period of brain development, the detrimental effects of early adversity are likely to be long lasting. Here we discuss the various ways adversity becomes neurobiologically embedded, and how the timing of such adversity plays an important role in determining outcomes. We conclude our p...
Source: Trends in Neurosciences - February 28, 2020 Category: Neuroscience Authors: Nelson CA, Gabard-Durnam LJ Tags: Trends Neurosci Source Type: research

Classification of Midbrain Dopamine Neurons Using Single-Cell Gene Expression Profiling Approaches.
Abstract Dysfunctional dopamine (DA) signaling has been associated with a broad spectrum of neuropsychiatric disorders, prompting investigations into how midbrain DA neuron heterogeneity may underpin this variety of behavioral symptoms. Emerging literature indeed points to functional heterogeneity even within anatomically defined DA clusters. Recognizing the need for a systematic classification scheme, several groups have used single-cell profiling to catalog DA neurons based on their gene expression profiles. We aim here not only to synthesize points of congruence but also to highlight key differences between the...
Source: Trends in Neurosciences - February 28, 2020 Category: Neuroscience Authors: Poulin JF, Gaertner Z, Moreno-Ramos OA, Awatramani R Tags: Trends Neurosci Source Type: research

Asymmetry Between Pre- and Postsynaptic Transient Nanodomains Shapes Neuronal Communication.
Abstract Synaptic transmission and plasticity are shaped by the dynamic reorganization of signaling molecules within pre- and postsynaptic compartments. The nanoscale organization of key effector molecules has been revealed by single-particle trajectory (SPT) methods. Interestingly, this nanoscale organization is highly heterogeneous. For example, presynaptic voltage-gated calcium channels (VGCCs) and postsynaptic ligand-gated ion channels such as AMPA receptors (AMPARs) are organized into so-called nanodomains where individual molecules are only transiently trapped. These pre- and postsynaptic nanodomains are cha...
Source: Trends in Neurosciences - February 28, 2020 Category: Neuroscience Authors: Heine M, Holcman D Tags: Trends Neurosci Source Type: research

Astrocytes and Microglia: In Sickness and in Health.
Abstract Healthy central nervous system (CNS) development and function require an intricate and balanced bidirectional communication between neurons and glia cells. In this review, we discuss the complementary roles of astrocytes and microglia in building the brain, including in the formation and refinement of synapses. We discuss recent evidence demonstrating how these interactions are coordinated in the transition from healthy physiology towards disease and discuss known and potential molecular mechanisms that mediate this cellular crosstalk. PMID: 32044129 [PubMed - as supplied by publisher] (Source: Trends in Neurosciences)
Source: Trends in Neurosciences - February 7, 2020 Category: Neuroscience Authors: Vainchtein ID, Molofsky AV Tags: Trends Neurosci Source Type: research

Nociceptor-Mast Cell Sensory Clusters as Regulators of Skin Homeostasis.
Abstract Recent studies revealed the existence of unique functional links between mast cells and nociceptors in the skin. Here, we propose that mast cells and nociceptors form a single regulatory unit in both physiology and disease. In this model, MrgprB2/X2 signaling is a primary mechanism by which mast cells functionally interact with nociceptors to form specialized neuroimmune clusters that regulate pain, inflammation, and itch. PMID: 32014258 [PubMed - as supplied by publisher] (Source: Trends in Neurosciences)
Source: Trends in Neurosciences - January 31, 2020 Category: Neuroscience Authors: Meixiong J, Basso L, Dong X, Gaudenzio N Tags: Trends Neurosci Source Type: research

Epithelial-Neuronal Communication in the Colon: Implications for Visceral Pain.
Abstract Visceral hypersensitivity and pain result, at least in part, from increased excitability of primary afferents that innervate the colon. In addition to intrinsic changes in these neurons, emerging evidence indicates that changes in lining epithelial cells may also contribute to increased excitability. Here we review recent studies on how colon epithelial cells communicate directly with colon afferents. Specifically, anatomical studies revealed specialized synaptic connections between epithelial cells and nerve fibers and studies using optogenetic activation of the epithelium showed initiation of pain-like ...
Source: Trends in Neurosciences - January 23, 2020 Category: Neuroscience Authors: Najjar SA, Davis BM, Albers KM Tags: Trends Neurosci Source Type: research