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https://www.readbyqxmd.com/read/29222993/supplementation-of-gamma-aminobutyric-acid-gaba-affects-temporal-but-not-spatial-visual-attention
#1
Anna Leonte, Lorenza S Colzato, Laura Steenbergen, Bernhard Hommel, Elkan G Akyürek
In a randomized, double-blind, and placebo-controlled experiment, the acute effects of gamma-aminobutyric acid (GABA) supplementation on temporal and spatial attention in young healthy adults were investigated. A hybrid two-target rapid serial visual presentation task was used to measure temporal attention and integration. Additionally, a visual search task was used to measure the speed and accuracy of spatial attention. While temporal attention depends primarily on the distribution of limited attentional resources across time, spatial attention represents the engagement and disengagement by relevant and irrelevant stimuli across the visual field...
December 6, 2017: Brain and Cognition
https://www.readbyqxmd.com/read/29222719/longevity-of-visual-improvements-following-transcorneal-electrical-stimulation-and-efficacy-of-retreatment-in-three-individuals-with-retinitis-pigmentosa
#2
Ava K Bittner, Kenneth Seger
PURPOSE: A small-scale randomized controlled trial conducted by our group found that four of seven retinitis pigmentosa (RP) subjects who received six weekly Transcorneal Electrical Stimulation (TES) sessions developed significant improvements in visual acuity (VA), quick contrast sensitivity function (qCSF), and/or Goldmann visual fields (GVF). We longitudinally monitored three of these participants for declining visual function due to natural RP progression to determine the duration of their responses and administered retreatments...
December 8, 2017: Graefe's Archive for Clinical and Experimental Ophthalmology
https://www.readbyqxmd.com/read/29221792/the-serotonin-hallucinogen-5-meo-dmt-alters-cortico-thalamic-activity-in-freely-moving-mice-regionally-selective-involvement-of-5-ht1a-and-5-ht2a-receptors
#3
REVIEW
Maurizio S Riga, Laia Lladó-Pelfort, Francesc Artigas, Pau Celada
5-MeO-DMT is a natural hallucinogen acting as serotonin 5-HT1A/5-HT2A receptor agonist. Its ability to evoke hallucinations could be used to study the neurobiology of psychotic symptoms and to identify new treatment targets. Moreover, recent studies revealed the therapeutic potential of serotonin hallucinogens in treating mood and anxiety disorders. Our previous results in anesthetized animals show that 5-MeO-DMT alters cortical activity via 5-HT1A and 5-HT2A receptors. Here, we examined 5-MeO-DMT effects on oscillatory activity in prefrontal (PFC) and visual (V1) cortices, and in mediodorsal thalamus (MD) of freely-moving wild-type (WT) and 5-HT2A-R knockout (KO2A) mice...
December 5, 2017: Neuropharmacology
https://www.readbyqxmd.com/read/29219962/predictors-of-long-term-neurological-outcomes-in-non-accidental-head-injury
#4
C F Chong, S L Misra, J A Escardo-Paton, S Dai
BackgroundNon-accidental head injury (NAI) is an inflicted injury usually on a child, often resulting in long-term neurological impairment and occasionally death. This study aimed to investigate the predictive values of acute findings, especially ocular, for long-term neurological outcomes.MethodsMedical records including retinal images of all children who attended the local Children's hospital with a diagnosis of NAI from over a period of 5 years were reviewed and data collected via the electronic patient record system...
December 8, 2017: Eye
https://www.readbyqxmd.com/read/29219756/awake-perimetry-testing-for-occipital-epilepsy-surgery
#5
Holger Joswig, John P Girvin, Warren T Blume, Jorge G Burneo, David A Steven
In the literature, there are few reports that provide a detailed account on the technique of visual electrocortical stimulation in the setting of resective surgery for occipital epilepsy. In this technical note, the authors describe how a 26-year-old male with long-standing occipital epilepsy underwent resective surgery under awake conditions, using electrocortical stimulation of the occipital lobe, with the aid of a laser pointer and a perimetry chart on a stand within his visual field. The eloquent primary visual cortex was found to overlap with the seizure onset zone that was previously determined with subdural electrodes...
December 8, 2017: Journal of Neurosurgery
https://www.readbyqxmd.com/read/29218881/data-driven-advice-for-applying-machine-learning-to-bioinformatics-problems
#6
Randal S Olson, William La Cava, Zairah Mustahsan, Akshay Varik, Jason H Moore
As the bioinformatics field grows, it must keep pace not only with new data but with new algorithms. Here we contribute a thorough analysis of 13 state-of-the-art, commonly used machine learning algorithms on a set of 165 publicly available classification problems in order to provide data-driven algorithm recommendations to current researchers. We present a number of statistical and visual comparisons of algorithm performance and quantify the effect of model selection and algorithm tuning for each algorithm and dataset...
2018: Pacific Symposium on Biocomputing
https://www.readbyqxmd.com/read/29218331/justpoint-identifying-colors-with-a-natural-user-interface
#7
Sergio Mascetti, Silvia D'Acquisto, Andrea Gerino, Mattia Ducci, Cristian Bernareggi, James M Coughlan
People with severe visual impairments usually have no way of identifying the colors of objects in their environment. While existing smartphone apps can recognize colors and speak them aloud, they require the user to center the object of interest in the camera's field of view, which is challenging for many users. We developed a smartphone app to address this problem that reads aloud the color of the object pointed to by the user's fingertip, without confusion from background colors. We evaluated the app with nine people who are blind, demonstrating the app's effectiveness and suggesting directions for improvements in the future...
October 2017: ASSETS Association for Computing Machinery
https://www.readbyqxmd.com/read/29218308/opportunities-for-crispr-cas9-gene-editing-in-retinal-regeneration-research
#8
REVIEW
Leah J Campbell, David R Hyde
While retinal degeneration and disease results in permanent damage and vision loss in humans, the severely damaged zebrafish retina has a high capacity to regenerate lost neurons and restore visual behaviors. Advancements in understanding the molecular and cellular basis of this regeneration response give hope that strategies and therapeutics may be developed to restore sight to blind and visually-impaired individuals. Our current understanding has been facilitated by the amenability of zebrafish to molecular tools, imaging techniques, and forward and reverse genetic approaches...
2017: Frontiers in Cell and Developmental Biology
https://www.readbyqxmd.com/read/29217689/dopamine-dependent-sensitization-of-rod-bipolar-cells-by-gaba-is-conveyed-through-wide-field-amacrine-cells
#9
Amanda M Travis, Stephanie J Heflin, Arlene A Hirano, Nicholas C Brecha, Vadim Y Arshavsky
Vertebrate retina has the remarkable ability to support visual function under conditions of limited illumination, including processing signals evoked by single photons. Dim light vision is regulated by several adaptive mechanisms. The mechanism explored in this study is responsible for increasing the light sensitivity and operational range of rod bipolar cells, the retinal neurons operating immediately downstream of rod photoreceptors. This sensitization is achieved through the sustained dopamine-dependent GABA release from other retinal neurons...
December 6, 2017: Journal of Neuroscience: the Official Journal of the Society for Neuroscience
https://www.readbyqxmd.com/read/29217027/optic-disc-hemorrhages-in-glaucoma-and-common-clinical-features
#10
Zeynep Kayaarasi Ozturker, Kristen Munro, Neeru Gupta
OBJECTIVE: To analyze optic nerve head stereophotographs for the presence of optic disc hemorrhages, and to describe bleeding patterns and patient characteristics. DESIGN: Retrospective, cross-sectional study. PARTICIPANTS: 1113 optic nerve stereophotograph pairs of 562 consecutive patients. METHODS: Stereophotographs were systematically reviewed for the presence of a disc hemorrhage with careful documentation of optic nerve head features...
December 2017: Canadian Journal of Ophthalmology. Journal Canadien D'ophtalmologie
https://www.readbyqxmd.com/read/29216459/pushing-the-boundaries-of-neuroimaging-with-optoacoustics
#11
REVIEW
Saak V Ovsepian, Ivan Olefir, Gil Westmeyer, Daniel Razansky, Vasilis Ntziachristos
With the central ability to visualize a variety of endogenous chromophores and biomarkers or exogenous contrast agents, optoacoustic (photoacoustic) imaging empowers new experimental capabilities for investigating brain mechanisms and functions. Here, the operational principles of optoacoustic neuroimaging are reviewed in conjunction with recent advances enabling high-resolution and real-time observation, which extend beyond the reach of optical imaging methods. Multiple implementations of optoacoustics for monitoring hemodynamics and neuro-vascular responses in the brain are showcased...
December 6, 2017: Neuron
https://www.readbyqxmd.com/read/29216195/reduced-visual-attention-in-heterogeneous-textures-is-reflected-in-occipital-alpha-and-theta-band-activity
#12
Tobias Feldmann-Wüstefeld, Makoto Miyakoshi, Marco Alessandro Petilli, Anna Schubö, Scott Makeig
Increasing context heterogeneity has been found to reduce attention deployment towards an embedded target item. Heterogeneity in visual search tasks is typically induced by segmenting the background into several perceptual groups. In the present study, however, context heterogeneity was induced by varying whole-field heterogeneity, i.e., the degree of distractor variability within the entire context. This allowed us to (i) more gradually vary context heterogeneity, and (ii) investigate attention deployment on a whole-field scale...
2017: PloS One
https://www.readbyqxmd.com/read/29215806/development-of-an-lcd-based-visual-field-system
#13
Jin Ho Joo, Jihyoung Lee, Heecheon You, Jaheon Kang
BACKGROUND: The present study investigated the diagnostic effectiveness of an LCD-based visual field testing system (LVF) in comparison with the standard automated perimetry Humphrey Field Analyzer II-750i (HFA). METHODS: A randomized controlled crossover study was conducted with 202 normal and 128 glaucomatous eyes using both LVF and HFA. The visual field testing systems were compared in terms of mean deviation (MD), pattern standard deviation (PSD), and area under the receiver operating characteristics curve (AUC) of MD and PSD differentiating the normal and glaucomatous eyes...
January 15, 2018: Journal of Korean Medical Science
https://www.readbyqxmd.com/read/29215034/local-field-potentials-are-induced-by-visually-evoked-spiking-activity-in-macaque-cortical-area-mt
#14
Moein Esghaei, Mohammad Reza Daliri, Stefan Treue
Local field potentials (LFP) have been the focus of many recent studies in systems neuroscience. However, the exact neural basis of these signals remains unclear. To address this question, we determined the relationship between LFP signals and another, much better understood, signature of neural activity: action potentials. Specifically, we focused on the relationship between the amplitude of stimulus-induced LFPs and the magnitude of spiking activity in visual cortex of non-human primates. Our trial-by-trial correlation analyses between these two components of extracellular signals in macaque visual cortex show that the spike rate is coupled to the LFP amplitude with a surprisingly long latency, typically 50 ms...
December 7, 2017: Scientific Reports
https://www.readbyqxmd.com/read/29214064/bronchoscopy-for-the-diagnosis-of-peripheral-lung-lesions
#15
REVIEW
Samjot Singh Dhillon, Kassem Harris
Peripheral pulmonary lesions (PPLs) are generally considered as lesions in the peripheral one-third of the lung although a precise definition and radiographic anatomical landmarks separating central and peripheral lesion does not yet exist. The radiographic detection of such lesions has increased significantly with the adoption of lung cancer screening programs. These lesions are not directly visible by regular flexible bronchoscopes as they are usually distal to the lobar and segmental bronchi. Traditionally, depending on location and clinical stage at presentation, these lesions were typically sampled by computerized tomography (CT) guided needle or surgical biopsy although some centers also used ultrasound and fluoroscopy guided percutaneous needle biopsy...
September 2017: Journal of Thoracic Disease
https://www.readbyqxmd.com/read/29213252/hemispheric-asymmetries-in-price-estimation-do-brain-hemispheres-attribute-different-monetary-values
#16
Felice Giuliani, Anita D'Anselmo, Luca Tommasi, Alfredo Brancucci, Davide Pietroni
The Spatial Numerical Association of Response Codes (SNARC) effect has been associated with a wide range of magnitude processing. This effect is due to an implicit relationship between numbers and horizontal space, according to which weaker magnitudes and smaller numbers are represented on the left, whereas stronger magnitudes and larger numbers are represented on the right. However, for some particular type of magnitudes such as price, judgments may be also influenced by perceived quality and thus involving valence attribution biases driven by brain asymmetries...
2017: Frontiers in Psychology
https://www.readbyqxmd.com/read/29213233/multisensory-and-modality-specific-influences-on-adaptation-to-optical-prisms
#17
Elena Calzolari, Federica Albini, Nadia Bolognini, Giuseppe Vallar
Visuo-motor adaptation to optical prisms displacing the visual scene (prism adaptation, PA) is a method used for investigating visuo-motor plasticity in healthy individuals and, in clinical settings, for the rehabilitation of unilateral spatial neglect. In the standard paradigm, the adaptation phase involves repeated pointings to visual targets, while wearing optical prisms displacing the visual scene laterally. Here we explored differences in PA, and its aftereffects (AEs), as related to the sensory modality of the target...
2017: Frontiers in Human Neuroscience
https://www.readbyqxmd.com/read/29213097/multiplexed-computations-in-retinal-ganglion-cells-of-a-single-type
#18
Stéphane Deny, Ulisse Ferrari, Emilie Macé, Pierre Yger, Romain Caplette, Serge Picaud, Gašper Tkačik, Olivier Marre
In the early visual system, cells of the same type perform the same computation in different places of the visual field. How these cells code together a complex visual scene is unclear. A common assumption is that cells of a single-type extract a single-stimulus feature to form a feature map, but this has rarely been observed directly. Using large-scale recordings in the rat retina, we show that a homogeneous population of fast OFF ganglion cells simultaneously encodes two radically different features of a visual scene...
December 6, 2017: Nature Communications
https://www.readbyqxmd.com/read/29213067/not-all-observed-actions-are-perceived-equally
#19
Artem Platonov, Guy A Orban
Action observation is the visual process analyzing the actions of others to determine their goals and how the actor's body (part) movements permit attaining those goals. Our recent psychophysical study demonstrated that 1) observed action (OA) perception differs from shape perception in viewpoint and duration dependence, and 2) accuracy and reaction times of OA discrimination are fitted by the proportional-rate diffusion model whereby a sensory stage provides noisy evidence that is accumulated up to a criterion or bound by a decision stage...
December 6, 2017: Scientific Reports
https://www.readbyqxmd.com/read/29211742/fear-of-falling-and-postural-reactivity-in-patients-with-glaucoma
#20
Fábio B Daga, Alberto Diniz-Filho, Erwin R Boer, Carolina P B Gracitelli, Ricardo Y Abe, Felipe A Medeiros
PURPOSE: To investigate the relationship between postural metrics obtained by dynamic visual stimulation in a virtual reality environment and the presence of fear of falling in glaucoma patients. METHODS: This cross-sectional study included 35 glaucoma patients and 26 controls that underwent evaluation of postural balance by a force platform during presentation of static and dynamic visual stimuli with head-mounted goggles (Oculus Rift). In dynamic condition, a peripheral translational stimulus was used to induce vection and assess postural reactivity...
2017: PloS One
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