SAGE Journal Articles

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Journal Article 1: Klingseisen, A.,& Lyons, D. A. (in press). Axonal regulation of central nervous system myelination: Structure and functionNeuroscientist.
doi: 10.1177/1073858417703030.

Abstract: Approximately half of the human brain consists of myelinated axons. Central nervous system (CNS) myelin is made by oligodendrocytes and is essential for nervous system formation, health, and function. Once thought simply as a static insulator that facilitated rapid impulse conduction, myelin is now known to be made and remodeled in to adult life. Oligodendrocytes have a remarkable capacity to differentiate by default, but many aspects of their development can be influenced by axons. However, how axons and oligodendrocytes interact and cooperate to regulate myelination in the CNS remains unclear. Here, we review recent advances in our understanding of how such interactions generate the complexity of myelination known to exist in vivo. We highlight intriguing results that indicate that the cross-sectional size of an axon alone may regulate myelination to a surprising degree. We also review new studies, which have highlighted diversity in the myelination of axons of different neuronal subtypes and circuits, and structure-function relationships, which suggest that myelinated axons can be exquisitely fine-tuned to mediate precise conduction needs. We also discuss recent advances in our understanding of how neuronal activity regulates CNS myelination, and aim to provide an integrated overview of how axon-oligodendrocyte interactions sculpt neuronal circuit structure and function.

Journal Article 2: Henry, L. C., Tremblay, S., & De Beaumont, L. (in press). Long-term effects of sports concussions: Bridging the neurocognitive repercussions of the injury with the newest neuroimaging data. Neuroscientist. 
doi: 10.1177/1073858416651034.

Abstract: Little is known of the long-term effects of sports-related concussion. Within the scientific literature, conclusions vary substantially where some work suggests there are no long-term consequences at all and other studies show rampant neurodegeneration thought to be caused by sometimes even a single concussive blow to the head. There is growing evidence that supports multiple long-term outcomes, showing both subclinical and clinically relevant changes in the brains of athletes, young and old alike. This article reviews the pathohistology of cerebral concussions and examines the extant literature with a focus on electrophysiological and neuroimaging findings. Neurobehavioral and neurocognitive changes are also reviewed, particularly as they are related to chronic traumatic encephalopathy. Lacunae within the literature are explored, and future research directions are proposed.

Journal Article 3: Arshavsky, Y. I. (in press). Neurons versus networks: The interplay between individual neurons and neural networks in cognitive functions. Neuroscientist. 
doi: 10.1177/1073858416670124.

Abstract: The main paradigm of cognitive neuroscience is the connectionist concept postulating that the higher nervous activity is performed through interactions of neurons forming complex networks, whereas the function of individual neurons is restricted to generating electrical potentials and transmitting signals to other cells. In this article, I describe the observations from three fields – neurolinguistics, physiology of memory, and sensory perception – that can hardly be explained within the constraints of a purely connectionist concept. Rather, these examples suggest that cognitive functions are determined by specific properties of individual neurons and, therefore, are likely to be accomplished primarily at the intracellular level. This view is supported by the recent discovery that the brain’s ability to create abstract concepts of particular individuals, animals, or places is performed by neurons (“concept cells”) sparsely distributed in the medial temporal lobe.

Journal Article 4: Gao, W., Lin, W., Grewen, K., & Gilmore, J. (2017). Functional connectivity of the infant human brain: Plastic and modifiable.Neuroscientist, 23(2), 169-184.
doi: 10.1177/1073858416635986.

Abstract: Infancy is a critical and immensely important period in human brain development. Subtle changes during this stage may be greatly amplified with the unfolding of different developmental processes, exerting far-reaching consequences. Studies of the structure and behavioral manifestations of the infant brain are fruitful. However, the specific functional brain mechanisms that enable the execution of different behaviors remained elusive until the advent of functional connectivity fMRI (fcMRI), which provides an unprecedented opportunity to probe the infant functional brain development in vivo. Since its inception, a burgeoning field of infant brain functional connectivity study has emerged and thrived during the past decade. In this review, we describe (1) findings of normal development of functional connectivity networks and their relationships to behaviors and (2) disruptions of the normative functional connectivity development due to identifiable genetic and/or environmental risk factors during the first 2 years of human life. Technical considerations of infant fcMRI are also provided. It is our hope to consolidate previous findings so that the field can move forward with a clearer picture toward the ultimate goal of fcMRI-based objective methods for early diagnosis/identification of risks and evaluation of early interventions to optimize developing functional connectivity networks in this critical developmental window.