Read by QxMD icon Read

neural coding

Kenneth S Henry, Kristina S Abrams, Johanna Forst, Matthew J Mender, Erikson G Neilans, Fabio Idrobo, Laurel H Carney
Vowels make a strong contribution to speech perception under natural conditions. Vowels are encoded in the auditory nerve primarily through neural synchrony to temporal fine structure and to envelope fluctuations rather than through average discharge rate. Neural synchrony is thought to contribute less to vowel coding in central auditory nuclei, consistent with more limited synchronization to fine structure and the emergence of average-rate coding of envelope fluctuations. However, this hypothesis is largely unexplored, especially in background noise...
October 20, 2016: Journal of the Association for Research in Otolaryngology: JARO
R Gajendra Reddy, Lenin Veeraval, Swati Maitra, Marylène Chollet-Krugler, Sophie Tomasi, Françoise Lohézic-Le Dévéhat, Joël Boustie, Sumana Chakravarty
BACKGROUND: Natural products from lichens are widely investigated for their biological properties, yet their potential as central nervous system (CNS) therapeutic agents is less explored. PURPOSE: The present study investigated the neuroactive properties of selected lichen compounds (atranorin, perlatolic acid, physodic acid and usnic acid), for their neurotrophic, neurogenic and acetylcholine esterase (AChE) activities. METHODS: Neurotrophic activity (neurite outgrowth) was determined using murine neuroblastoma Neuro2A cells...
November 15, 2016: Phytomedicine: International Journal of Phytotherapy and Phytopharmacology
Nikolaus Kriegeskorte, Katherine R Storrs
"Grid cells" encode an animal's location and direction of movement in 2D physical environments via regularly repeating receptive fields. Constantinescu et al. (2016) report the first evidence of grid cells for 2D conceptual spaces. The work has exciting implications for mental representation and shows how detailed neural-coding hypotheses can be tested with bulk population-activity measures.
October 19, 2016: Neuron
Yongseok Yoo, Woori Kim
Neural systems are inherently noisy. One well-studied example of a noise reduction mechanism in the brain is the population code, where representing a variable with multiple neurons allows the encoded variable to be recovered with fewer errors. Studies have assumed ideal observer models for decoding population codes, and the manner in which information in the neural population can be retrieved remains elusive. This letter addresses a mechanism by which realistic neural circuits can recover encoded variables...
October 20, 2016: Neural Computation
Zhuo Wang, Alan A Stocker, Daniel D Lee
The efficient coding hypothesis assumes that biological sensory systems use neural codes that are optimized to best possibly represent the stimuli that occur in their environment. Most common models use information-theoretic measures, whereas alternative formulations propose incorporating downstream decoding performance. Here we provide a systematic evaluation of different optimality criteria using a parametric formulation of the efficient coding problem based on the Lp reconstruction error of the maximum likelihood decoder...
October 20, 2016: Neural Computation
William Severa, Ojas Parekh, Conrad D James, James B Aimone
The dentate gyrus forms a critical link between the entorhinal cortex and CA3 by providing a sparse version of the signal. Concurrent with this increase in sparsity, a widely accepted theory suggests the dentate gyrus performs pattern separation-similar inputs yield decorrelated outputs. Although an active region of study and theory, few logically rigorous arguments detail the dentate gyrus's (DG) coding. We suggest a theoretically tractable, combinatorial model for this action. The model provides formal methods for a highly redundant, arbitrarily sparse, and decorrelated output signal...
October 20, 2016: Neural Computation
Hyejung Won, Luis de la Torre-Ubieta, Jason L Stein, Neelroop N Parikshak, Jerry Huang, Carli K Opland, Michael J Gandal, Gavin J Sutton, Farhad Hormozdiari, Daning Lu, Changhoon Lee, Eleazar Eskin, Irina Voineagu, Jason Ernst, Daniel H Geschwind
Three-dimensional physical interactions within chromosomes dynamically regulate gene expression in a tissue-specific manner. However, the 3D organization of chromosomes during human brain development and its role in regulating gene networks dysregulated in neurodevelopmental disorders, such as autism or schizophrenia, are unknown. Here we generate high-resolution 3D maps of chromatin contacts during human corticogenesis, permitting large-scale annotation of previously uncharacterized regulatory relationships relevant to the evolution of human cognition and disease...
October 19, 2016: Nature
Xiaojing Qiao, Yahui Liu, Peiqiang Li, Zhongzhong Chen, Huili Li, Xueyan Yang, Richard H Finnell, Zhangmin Yang, Ting Zhang, Bin Qiao, Yufang Zheng, Hongyan Wang
The planar cell polarity (PCP) pathway is critical for proper embryonic development of the neural tube and heart. Mutations in these genes have previously been implicated in the pathogenesis of neural tube defects (NTDs), but not in congenital heart defects (CHDs) in humans. We systematically identified the mutation patterns of CELSR1-3 , one family of the core PCP genes, in human cohorts composed of 352 NTD cases, 412 CHD cases, and matched controls. A total of 72 disease-specific rare novel coding mutations were identified, of which 37 were identified in CHD cases, and 36 were identified in NTD patients...
October 18, 2016: Clinical Science (1979-)
Tosoni Annalisa, Guidotti Roberto, Del Gratta Cosimo, Committeri Giorgia, Sestieri Carlo
The human ventral occipito-temporal cortex (OTC) contains areas specialized for particular perceptual/semantic categories, such as faces (fusiform face area, FFA) and places (parahippocampal place area, PPA). This organization has been interpreted as reflecting the visual structure of the world, i.e. perceptual similarity and/or eccentricity biases. However, recent functional magnetic resonance imaging (fMRI) studies have shown not only that regions of the OTC are modulated by non-visual, action-related object properties but also by motor planning and execution, although the functional role and specificity of this motor-related activity are still unclear...
October 15, 2016: Neuropsychologia
Ming Zhang, Lutao Liu, Ming Diao
In this paper, an automatic radar waveform recognition system in a high noise environment is proposed. Signal waveform recognition techniques are widely applied in the field of cognitive radio, spectrum management and radar applications, etc. We devise a system to classify the modulating signals widely used in low probability of intercept (LPI) radar detection systems. The radar signals are divided into eight types of classifications, including linear frequency modulation (LFM), BPSK (Barker code modulation), Costas codes and polyphase codes (comprising Frank, P1, P2, P3 and P4)...
October 12, 2016: Sensors
Renée M Symonds, Wei Wei Lee, Adam Kohn, Odelia Schwartz, Sarah Witkowski, Elyse S Sussman
The auditory mismatch negativity (MMN) component of event-related potentials (ERPs) has served as a neural index of auditory change detection. MMN is elicited by presentation of infrequent (deviant) sounds randomly interspersed among frequent (standard) sounds. Deviants elicit a larger negative deflection in the ERP waveform compared to the standard. There is considerable debate as to whether the neural mechanism of this change detection response is due to release from neural adaptation (neural adaptation hypothesis) or from a prediction error signal (predictive coding hypothesis)...
October 17, 2016: Brain Topography
Neloy Kumar Chakroborty, Randolf Menzel, Marco Schubert
Ca(2+) imaging techniques were applied to investigate the neuronal behavior of projection neurons in the honeybee antennal lobe to examine the effects of long lasting adaptation on odorant coding. Responses to 8 test odorants were measured before, during and after an odor adaptation phase. Bees were exposed to the adapting odor for 30 minutes. Test odorant responses were only recorded from a sub-population of accessible glomeruli on the antennal lobe surface. Projection neurons, the output neurons of the antennal lobes, are projecting through the lateral, mediolateral and medial antennal lobe tract to higher centers of the olfactory pathway...
October 17, 2016: European Journal of Neuroscience
Steven W Barger
Ask any neuroscientist to name the most profound discoveries in the field in the past 60 years, and at or near the top of the list will be a phenomenon or technique related to genes and their expression. Indeed, our understanding of genetics and gene regulation has ushered in whole new systems of knowledge and new empirical approaches, many of which could not have even been imagined prior to the molecular biology boon of recent decades. Neurochemistry, in the classic sense, intersects with these concepts in the manifestation of neuropeptides, obviously dependent upon the central dogma (the established rules by which DNA sequence is eventually converted into protein primary structure) not only for their conformation but also for their levels and locales of expression...
October 17, 2016: Journal of Neurochemistry
Akihiro Eguchi, Simon M Stringer
As Rubin's famous vase demonstrates, our visual perception tends to assign luminance contrast borders to one or other of the adjacent image regions. Experimental evidence for the neuronal coding of such border-ownership in the primate visual system has been reported in neurophysiology. We have investigated exactly how such neural circuits may develop through visually-guided learning. More specifically, we have investigated through computer simulation how top-down connections may play a fundamental role in the development of border ownership representations in the early cortical visual layers V1/V2...
October 13, 2016: Neurobiology of Learning and Memory
Braden A W Brinkman, Alison I Weber, Fred Rieke, Eric Shea-Brown
Neural circuits reliably encode and transmit signals despite the presence of noise at multiple stages of processing. The efficient coding hypothesis, a guiding principle in computational neuroscience, suggests that a neuron or population of neurons allocates its limited range of responses as efficiently as possible to best encode inputs while mitigating the effects of noise. Previous work on this question relies on specific assumptions about where noise enters a circuit, limiting the generality of the resulting conclusions...
October 2016: PLoS Computational Biology
Douglas McLelland, Rufin VanRullen
Several theories have been advanced to explain how cross-frequency coupling, the interaction of neuronal oscillations at different frequencies, could enable item multiplexing in neural systems. The communication-through-coherence theory proposes that phase-matching of gamma oscillations between areas enables selective processing of a single item at a time, and a later refinement of the theory includes a theta-frequency oscillation that provides a periodic reset of the system. Alternatively, the theta-gamma neural code theory proposes that a sequence of items is processed, one per gamma cycle, and that this sequence is repeated or updated across theta cycles...
October 2016: PLoS Computational Biology
Ilaria Bergese, Simona Frigerio, Marco Clari, Emanuele Castagno, Antonietta De Clemente, Elena Ponticelli, Enrica Scavino, Paola Berchialla
OBJECTIVES: Return visit (RV) to the emergency department (ED) is considered a benchmarking clinical indicator for health care quality. The purpose of this study was to develop a predictive model for early readmission risk in pediatric EDs comparing the performances of 2 learning machine algorithms. METHODS: A retrospective study based on all children younger than 15 years spontaneously returning within 120 hours after discharge was conducted in an Italian university children's hospital between October 2012 and April 2013...
October 6, 2016: Pediatric Emergency Care
Brandon S Coventry, Aravindakshan Parthasarathy, Alexandra L Sommer, Edward L Bartlett
Particle swarm optimization (PSO) has gained widespread use as a general mathematical programming paradigm and seen use in a wide variety of optimization and machine learning problems. In this work, we introduce a new variant on the PSO social network and apply this method to the inverse problem of input parameter selection from recorded auditory neuron tuning curves. The topology of a PSO social network is a major contributor to optimization success. Here we propose a new social network which draws influence from winner-take-all coding found in visual cortical neurons...
October 10, 2016: Journal of Computational Neuroscience
Alexei L Vyssotski, Anna E Stepien, Georg B Keller, Richard H R Hahnloser
What cortical inputs are provided to motor control areas while they drive complex learned behaviors? We study this question in the nucleus interface of the nidopallium (NIf), which is required for normal birdsong production and provides the main source of auditory input to HVC, the driver of adult song. In juvenile and adult zebra finches, we find that spikes in NIf projection neurons precede vocalizations by several tens of milliseconds and are insensitive to distortions of auditory feedback. We identify a local isometry between NIf output and vocalizations: quasi-identical notes produced in different syllables are preceded by highly similar NIf spike patterns...
October 2016: PLoS Biology
William A Liberti, Jeffrey E Markowitz, L Nathan Perkins, Derek C Liberti, Daniel P Leman, Grigori Guitchounts, Tarciso Velho, Darrell N Kotton, Carlos Lois, Timothy J Gardner
Motor skills can be maintained for decades, but the biological basis of this memory persistence remains largely unknown. The zebra finch, for example, sings a highly stereotyped song that is stable for years, but it is not known whether the precise neural patterns underlying song are stable or shift from day to day. Here we demonstrate that the population of projection neurons coding for song in the premotor nucleus, HVC, change from day to day. The most dramatic shifts occur over intervals of sleep. In contrast to the transient participation of excitatory neurons, ensemble measurements dominated by inhibition persist unchanged even after damage to downstream motor nerves...
October 10, 2016: Nature Neuroscience
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"