In this work, we present a novel methodology for performing the supervised classification of time-ordered noisy data; we call this methodology Entropic Sparse Probabilistic Approximation with Markov regularization (eSPA-Markov). It is an extension of entropic learning methodologies, allowing the simultaneous learning of segmentation patterns, entropy-optimal feature space discretizations, and Bayesian classification rules. We prove the conditions for the existence and uniqueness of the learning problem solution and propose a one-shot numerical learning algorithm that-in the leading order-scales linearly in dimension.
View Article and Find Full Text PDFSmall data learning problems are characterized by a significant discrepancy between the limited number of response variable observations and the large feature space dimension. In this setting, the common learning tools struggle to identify the features important for the classification task from those that bear no relevant information and cannot derive an appropriate learning rule that allows discriminating among different classes. As a potential solution to this problem, here we exploit the idea of reducing and rotating the feature space in a lower-dimensional gauge and propose the gauge-optimal approximate learning (GOAL) algorithm, which provides an analytically tractable joint solution to the dimension reduction, feature segmentation, and classification problems for small data learning problems.
View Article and Find Full Text PDFAnandamide (AEA) is an endogenous ligand of the cannabinoid CB1 and CB2 receptors, being a component of the endocannabinoid signaling system, which supports the maintenance or regaining of neural homeostasis upon internal and external challenges. AEA is thought to play a protective role against the development of pathological states after prolonged stress exposure, including depression and generalized anxiety disorder. Here, we used the chronic social defeat (CSD) stress as an ethologically valid model of chronic stress in male mice.
View Article and Find Full Text PDFFront Cell Dev Biol
August 2022
Spontaneous activity plays a crucial role in brain development by coordinating the integration of immature neurons into emerging cortical networks. High levels and complex patterns of spontaneous activity are generally associated with low rates of apoptosis in the cortex. However, whether spontaneous activity patterns directly encode for survival of individual cortical neurons during development remains an open question.
View Article and Find Full Text PDFThe main neurotransmitter in the brain responsible for the inhibition of neuronal activity is γ-aminobutyric acid (GABA). It plays a crucial role in circuit formation during development, both via its primary effects as a neurotransmitter and also as a trophic factor. The GABA receptors (GABARs) are G protein-coupled metabotropic receptors; on one hand, they can influence proliferation and migration; and, on the other, they can inhibit cells by modulating the function of K and Ca channels, doing so on a slower time scale and with a longer-lasting effect compared to ionotropic GABA receptors.
View Article and Find Full Text PDFMutations in TSC1 or TSC2 genes are linked to alterations in neuronal function which ultimately lead to the development of a complex neurological phenotype. Here we review current research on the effects that reduction in TSC1 or TSC2 can produce on the developing neural network. A crucial feature of the disease pathophysiology appears to be an early deviation from typical neurodevelopment, in the form of structural abnormalities.
View Article and Find Full Text PDFThe TSC1 and TSC2 tumor suppressor genes control the activity of mechanistic target of rapamycin (mTOR) pathway. Elevated activity of this pathway in Tsc2 mouse model leads to reduction of postsynaptic GABA receptor-mediated inhibition and hyperexcitability in the medial prefrontal cortex (mPFC). In this study, we asked whether presynaptic GABA receptors (GABARs) can compensate this shift of hyperexcitability.
View Article and Find Full Text PDFLoss-of-function mutation in one of the tumor suppressor genes TSC1 or TSC2 is associated with several neurological and psychiatric diseases, including autism spectrum disorders (ASDs). As an imbalance between excitatory and inhibitory neurotransmission, E/I ratio is believed to contribute to the development of these disorders, we investigated synaptic transmission during the first postnatal month using the Tsc2+/- mouse model. Electrophysiological recordings were performed in acute brain slices of medial prefrontal cortex.
View Article and Find Full Text PDFMyelination in the central nervous system depends on interactions between axons and oligodendrocyte precursor cells (OPCs). Action potentials in an axon can be followed by release of biologically active substances, like glutamate, which can instruct OPCs to start myelination. Myelin Basic Protein (MBP) is an "executive molecule of myelin" required for the formation of compact myelin.
View Article and Find Full Text PDFUnlabelled: The reduction of echocardiographic left ventricular (LV) mass and the change toward a less concentric geometry during antihypertensive treatment are independently associated with a better prognosis. Blood pressure-lowering treatment may reduce cardiac hypertrophy, although different effect on changes of LV mass have been reported among antihypertensive drug classes, while changes in echocardiographic evaluated LV geometry have not been systemically evaluated. It is not yet clear whether antihypertensive drugs may influence LV geometry.
View Article and Find Full Text PDFOligodendrocytes in the CNS myelinate neuronal axons, facilitating rapid propagation of action potentials. Myelin basic protein (MBP) is an essential component of myelin and its absence results in severe hypomyelination. In oligodendrocyte lineage cell (OLC) monocultures MBP synthesis starts at DIV4.
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