Search results for "neuron"

Recognizing actions with the associative self-organizing map

2013

When artificial agents interact and cooperate with other agents, either human or artificial, they need to recognize others’ actions and infer their hidden intentions from the sole observation of their surface level movements. Indeed, action and intention understanding in humans is believed to facilitate a number of social interactions and is supported by a complex neural substrate (i.e. the mirror neuron system). Implementation of such mechanisms in artificial agents would pave the route to the development of a vast range of advanced cognitive abilities, such as social interaction, adaptation, and learning by imitation, just to name a few. We present a first step towards a fully-fledged int…

A Comparison between Habituation and Conscience mechanism in Self–Organizing Maps

2006

In this letter, a preliminary study of habituation in self-organizing networks is reported. The habituation model implemented allows us to obtain a faster learning process and better clustering performances. The liabituable neuron is a generalization of the typical neuron and can be used in many self-organizing network models. The habituation mechanism is implemented in a SOM and the clustering performances of the network are compared to the conscience learning mechanism that follows roughly the same principle but is less sophisticated.

The generation of oligodendroglial cells is preserved in the rostral migratory stream during aging

2013

The subventricular zone (SVZ) is the largest source of newly generated cells in the adult mammalian brain. SVZ-derived neuroblasts migrate via the rostral migratory stream (RMS) to the olfactory bulb (OB), where they differentiate into mature neurons. Additionally, a small proportion of SVZ-derived cells contribute to the generation of myelinating oligodendrocytes. The production of new cells in the SVZ decreases during aging, affecting the incorporation of new neurons into the OB. However, the age-related changes that occur across the RMS are not fully understood. In this study we evaluate how aging affects the cellular organization of migrating neuroblast chains, the proliferation, and th…

Regulation of the p19(Arf)/p53 pathway by histone acetylation underlies neural stem cell behavior in senescence-prone SAMP8 mice.

2015

Brain aging is associated with increased neurodegeneration and reduced neurogenesis. B1/neural stem cells (B1-NSCs) of the mouse subependymal zone (SEZ) support the ongoing production of olfactory bulb interneurons, but their neurogenic potential is progressively reduced as mice age. Although age-related changes in B1-NSCs may result from increased expression of tumor suppressor proteins, accumulation of DNA damage, metabolic alterations, and microenvironmental or systemic changes, the ultimate causes remain unclear. Senescence-accelerated-prone mice (SAMP8) relative to senescence-accelerated-resistant mice (SAMR1) exhibit signs of hastened senescence and can be used as a model for the stud…

Nicotine-induced FGF-2 mRNA in rat brain is preserved during aging

2004

Indirect trophic actions of nicotine on brain during aging are suggested from observations describing nicotine as a cognitive enhancer, increasing vigilance and improving learning and memory, and both in vitro and in vivo models have demonstrated neuroprotective effects of nAChR agonists. Previously, we have reported that an acute intermittent (-)nicotine treatment significantly increases fibroblast growth factor-2 (FGF-2) mRNA and protein in several brain regions of rat brain. The present study was designed to analyse if nicotine-induced FGF-2 expression in the rat brain was preserved during aging. Using in situ hybridization and quantitative RNase protection assay the present paper report…

Sensory preconditioning in newborn rabbits: from common to distinct odor memories.

2013

Brief Communication; International audience; This study evaluated whether olfactory preconditioning is functional in newborn rabbits and based on joined or independent memory of odorants. First, after exposure to odorants A+B, the conditioning of A led to high responsiveness to odorant B. Second, responsiveness to B persisted after amnesia of A. Third, preconditioning was also functional with two overlapping pairs of odorants (A+B and B+C) and amnesia of one odorant did not affect memory of the others. Thus, incidental pairing of odorants allows reinforcement of one odorant to implicitly reinforce the others, the bond then vanishes, and the memory of each element becomes independent.

Corrigendum: Both attention and prediction are necessary for adaptive neuronal tuning in sensory processing

2017

Chapter 18 - Sensory Evaluation—Profiling and Preferences

2017

International audience; Tasting has always been at the heart of coffee growing and production. Expert coffee tasting prevails while applying a correct and structured sensory evaluation still requires improvement. In reality, the key actors of the coffee sensory assessment all along the value chain are the expert coffee taster, the sensory analyst, and the consumer. A major challenge for sensory evaluation in coffee is bridging the gap between the expert tasters and consumers. It is especially important in coffee because, as a natural crop product, supplies and the quality of those supplies constantly change, and consumer preferences evolve over time. Thanks to the continuous innovation in t…

A Mushroom Bodies inspired spiking network for classification and sequence learning

2015

Sequence learning is a complex capability shown by living beings, able to extract information from the environment. Looking into the insect world, there are several examples where the presentation time of specific stimuli is considered to select the proper behavioural response. On the basis of previously developed neural models for sequence learning, inspired by the Drosophila melanogaster, a new formalization of key brain structures involved in the process is here provided. The input classification is performed through resonant neurons, stimulated by the complex dynamics generated in a lattice of recurrent spiking neurons modelling the Mushroom Bodies neuropile in the insect brain. The net…

Extraction of ERP from EEG data

2007

In this article, a simple but novel technique for extracting a linear subspace related to event related potentials (ERPs) from ElectroEncephaloGraphy (EEG) data is introduced. The technique consists of a sequence of basic linear operations applied to multidimensional EEG data in a problem-specific manner. The derivation of the proposed technique is given and results with real data are described together with overall conclusions.