Cognitive Neuroscience of Dyslexia

2018 ◽  
Vol 49 (4) ◽  
pp. 798-809 ◽  
Author(s):  
Anila M. D'Mello ◽  
John D. E. Gabrieli

Purpose This review summarizes what is known about the structural and functional brain bases of dyslexia. Method We review the current literature on structural and functional brain differences in dyslexia. This includes evidence about differences in gray matter anatomy, white matter connectivity, and functional activations in response to print and language. We also summarize findings concerning brain plasticity in response to interventions. Results We highlight evidence relating brain function and structure to instructional issues such as diagnosis and prognosis. We also highlight evidence about brain differences in early childhood, before formal reading instruction in school, which supports the importance of early identification and intervention. Conclusion Neuroimaging studies of dyslexia reveal how the disorder is related to differences in structure and function in multiple neural circuits.

2021 ◽  
Author(s):  
Elie Fink ◽  
Matthieu Louis

Animals differ in their appearances and behaviors. While many genetic studies have addressed the origins of phenotypic differences between fly species, we are still lacking a quantitative assessment of the variability in the way different fly species behave. We tackled this question in one of the most robust behaviors displayed by Drosophila: chemotaxis. At the larval stage, Drosophila melanogaster navigate odor gradients by combining four sensorimotor routines in a multilayered algorithm: a modulation of the overall locomotor speed and turn rate; a bias in turning during down-gradient motion; a bias in turning toward the gradient; the local curl of trajectories toward the gradient ("weathervaning"). Using high-resolution tracking and behavioral quantification, we characterized the olfactory behavior of eight closely related species of the Drosophila group in response to 19 ecologically-relevant odors. Significant changes are observed in the receptive field of each species, which is consistent with the rapid evolution of the peripheral olfactory system. Our results reveal substantial inter-species variability in the algorithms directing larval chemotaxis. While the basic sensorimotor routines are shared, their parametric arrangements can vary dramatically across species. The present analysis sets the stage for deciphering the evolutionary relationships between the structure and function of neural circuits directing orientation behaviors in Drosophila.


2019 ◽  
Vol 29 (5) ◽  
pp. 640-656 ◽  
Author(s):  
Mark Povich

Autonomist accounts of cognitive science suggest that cognitive model building and theory construction (can or should) proceed independently of findings in neuroscience. Common functionalist justifications of autonomy rely on there being relatively few constraints between neural structure and cognitive function. In contrast, an integrative mechanistic perspective stresses the mutual constraining of structure and function. In this article, I show how Model-Based Cognitive Neuroscience (MBCN) epitomizes the integrative mechanistic perspective and concentrates the most revolutionary elements of the cognitive neuroscience revolution. I also show how the prominent subset account of functional realization supports the integrative mechanistic perspective I take on MBCN and use it to clarify the intralevel and interlevel components of integration.


Author(s):  
Κατερίνα Μανιαδάκη

The aim of this paper is to provide evidence regarding the necessity and the effectiveness of early intervention for ADHD, by reviewing the most important international early intervention programs for ADHD and by presenting a relevant program implemented in Greece, based on the multi-level approach in developmental psychopathology. These programs are underpinned theoretically by the biopsychosocial epigenetic model which claims that ADHD is not just the outcome of structural and functional neurobiological deficits but results from the dynamic interplay among genetic, neurophysiological, neurochemical, and environmental factors, affecting brain structure and function early in the process of development. Early intervention focuses on those processes that take place very early in development and have a causal relationship with ADHD, with the aim of modifying the underlying neurophysiology and producing generalized long-lasting change. The efficacy of early intervention mainly lies in the fact that it takes place during a period when brain plasticity is great. Plasticity is an intrinsic property of the brain that ensures dynamic modifications at multiple levels of neural organization, allowing the brain to process, encode, and implement new knowledge. Although this neuronal development is to a great extent genetically programmed, it is widely acknowledged that environment also plays a major role through the process of epigenesis by moderating gene expression with subsequent alterations in brain structure and function and allowing even modification of certain deficient structures.


Author(s):  
Francois P. Retief ◽  
Louise Cilliers

In Ancient Egypt mummification was associated with extensive organ resection, but the brain was removed through a hole cut in the ethnocide bone. It was thus not observed as an organ. Greek writers of the 6th and 5th centuries BC originally said the brain was the seat of intelligence, the organ of sensory perception and partially the origin of sperm. The substance pneuma, originating from fresh air, played an essential role in brain function. Hippocrates initially described the brain as a double organ, covered by meninges and responsible for perception. Contemporaries like Plato, Aristotle and Diocles confirmed the findings though the latter two considered the heart to be the centre of intelligence. During the late 4th century BC, with the onset of the Hellenistic era of medicine, dissection of the human body was temporarily allowed at the medical school of Alexandria, and this led to a remarkable advance in the understanding of human anatomy and physiology under Herophilus and Erasistratus. Their excellent descriptions of the structure and function of the brain was only matched and surpassed by Galen in the 2nd century AD.


Author(s):  
Andrew Poppe ◽  
Angus W. MacDonald III

This chapter describes a cognitive neuroscience approach to understanding the psychological and neural processes that underlie personality and behavior. It explicates the utility of the cognitive neuroscience approach and the fundamental principles of the methods and how to interpret the findings. The chapter reviews the different neuroimaging tools and approaches that can be used to investigate brain structure and function. In doing so, it provides detailed information about what each method measures and how issues to consider when evaluating these measurements and their functional significance. The chapter provides the reader an appreciation of how understanding brain structure and function in vivo can serve as a bridge between molecular/genetic and symptom-based data to enrich the pathophysiology of personality disorders.


Author(s):  
John Parrington

This book draws on the latest research on the human brain to show how it differs strikingly from those of other animals in its structure and function at molecular and cellular level. It argues that this ‘shift’, enlarging the brain, giving it greater flexibility and enabling higher functions such as imagination, was driven by tool use, but especially by the development of one remarkable tool—language. The complex social interaction brought by language opened up the possibility of shared conceptual worlds, enriched with rhythmic sounds and images that could be drawn on cave walls. This transformation enabled modern humans to generate an exceptional human consciousness, a sense of self that arises as a product of our brain biology and the social interactions we experience. Linking early work by the Russian psychologist Lev Vygotsky to the findings of modern neuroscience, the book also explores how language, culture, and society mediate brain function, and what this view of the human mind may bring to our understanding and treatment of mental illness.


2007 ◽  
Vol 30 (2) ◽  
pp. 174-178 ◽  
Author(s):  
Richard J. Haier ◽  
Rex E. Jung

AbstractThe commentaries address conceptual issues ranging from our narrow focus on neuroimaging to the various definitions of intelligence. The integration of the P-FIT and data from cognitive neuroscience is particularly important and considerable consistency is found. Overall, the commentaries affirm that advances in neuroscience techniques have caused intelligence research to enter a new phase. The P-FIT is recognized as a reasonable empirical framework to test hypotheses about the relationship of brain structure and function with intelligence and reasoning.


2020 ◽  
Author(s):  
Adam Haber ◽  
Elad Schneidman

ABSTRACTThe mapping of the wiring diagrams of neural circuits promises to allow us to link structure and function of neural networks. Current approaches to analyzing connectomes rely mainly on graph-theoretical tools, but these may downplay the complex nonlinear dynamics of single neurons and networks, and the way networks respond to their inputs. Here, we measure the functional similarity of simulated networks of neurons, by quantifying the similitude of their spiking patterns in response to the same stimuli. We find that common graph theory metrics convey little information about the similarity of networks’ responses. Instead, we learn a functional metric between networks based on their synaptic differences, and show that it accurately predicts the similarity of novel networks, for a wide range of stimuli. We then show that a sparse set of architectural features - the sum of synaptic inputs that each neuron receives and the sum of each neuron’s synaptic outputs - predicts the functional similarity of networks of up to 100 cells, with high accuracy. We thus suggest new architectural design principles that shape the function of neural networks, which conform with experimental evidence of homeostatic mechanisms.


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