Search results for "Spatial"
showing 10 items of 2121 documents
Impact of the pupil size – central optical zone diameter relationship on visual performance in aspheric multifocal contact lenses
2020
Abstract Purpose To determine the impact of different central optical zone diameters (COZDs), obtained from pupil size, on the visual performance of presbyopic subjects fitted with centre-distance simultaneous-image multifocal contact lenses (SIMCLs). Methods Thirty-two presbyopic volunteers, between 45–58 years of age, participated in this prospective, controlled, double-blind study. Subjects were fitted with 5 centre-distance SIMCLs of variable COZD, determined from the measurement of pupil size under photopic light conditions and corresponding to 60, 70, 80, 90 and 100 % of pupil diameter. Subjects visual performance was evaluated through the measurement of distance, intermediate and nea…
<p>Multimodal Evaluation of Visual Function in Geographic Atrophy versus Normal Eyes</p>
2020
Purpose To comprehensively evaluate visual function in eyes with geographic atrophy (GA) as compared to normal eyes. Patients and Methods Sixty-three eyes from 63 patients ≥50 years old were recruited for this observational study; 31 were identified as normal macular health eyes and 32 with GA. Visual function was tested with best corrected visual acuity (BCVA), low luminance visual acuity (LLVA), low luminance deficit (LLD), reading speed, macular integrity microperimetry, fixation stability, and contrast sensitivity function (CSF). Anatomic function was evaluated with spectral-domain optical coherence tomography (SD-OCT) and fundus autofluorescence (FAF). Quality of life and vision were a…
Temporal and Spatial Evolution of Cortical Blood Flow in the Penumbra of Venous Infarcts
2001
A cortical venous infarction model has been evaluated regarding the temporal and spatial evolution of regional flow reduction. Two cortical veins were occluded photochemically with rose bengal and fiberoptic illumination. Seven rats served to demonstrate effects on regional cortical blood flow using laser Doppler scanning. After two-vein occlusion, there was a widespread reduction of flow that gradually deteriorated after vein occlusion when regional cortical flow in a 3.5 x 7.0 mm window: after 15 min it had decreased to 57.8% ± 8.0%, and after 75 min it was 34.3% ± 5.4%. Infarct volumes as determined in 10 rats 5 days after two-vein occlusion had an average size of 3.6 ± 0.7 mm3. The data…
Perampanel and Visuospatial Skills in Children With Epilepsy
2021
Introduction: Perampanel (PER) is a non-competitive AMPA glutamate receptor antagonist approved for focal and generalized seizures as add-on therapy. PER does not seem to negatively affect the cognitive profile in children and adolescents, but its influence on visuospatial abilities is still to be assessed. The aim of our study was to assess visuospatial skills through a standardized neuropsychological evaluation in adolescents taking PER for 12 months.Methods: Our sample included 46 adolescents aged 12–18 years with focal and generalized drug-resistant epilepsy already in therapy with one or two antiseizure medications. Changes in visuospatial perception and memory were assessed by the Rey…
Transcranial Direct Current Stimulation over the Right Inferior Parietal Cortex Reduces Transposition Errors in a Syllabic Reordering Task
2021
Evidence derived from functional imaging and brain-lesion studies has shown a strong left lateralization for language, and a complementary right hemisphere dominance for visuospatial abilities. Nevertheless, the symmetrical functional division of the two hemispheres gives no reason for the complexity of the cognitive operations involved in carrying out a linguistic task. In fact, a growing number of neuroimaging and neurostimulation studies suggest a possible right hemisphere involvement in language processing. The objective of this work was to verify the contribution of the left and right parietal areas in a phonological task. We applied anodal transcranial direct current stimulation (tDCS…
Innovation in Neurosurgery: The Concept of Cognitive Mapping
2019
In recent years, advances in cortical-subcortical mapping, intraoperative neurophysiology, and neuropsychology have increased the ability to remove intrinsic brain tumors, expanding indications and maximizing the extent of resection. This has provided a significant improvement in progression-free survival, time of malignant transformation (in low-grade gliomas), and overall survival. Although current techniques enable preservation of language and motor functions during surgery, the maintenance of a complex set of functions defined with the term cognition is not always achievable. Cognition is defined as every neural process underlying a high human function and includes motor haptic and visu…
P 96. Prismatic lenses as a novel tool to directionally manipulate motor cortex excitability: Evidence from paired-pulse TMS
2013
Introduction Prismatic adaptation (PA) is a visuo-motor procedure requiring participants to adapt to prismatic lenses shifting the visual scene horizontally. Such an adaptation produces a phenomenon called “after-effect”, opposite to the side of lenses deviation. The after-effect has been frequently associated with a shift of spatial attention in the same direction and with a restoration of hemispatial neglect symptoms. PA has captured the interest of neuroscientists in the last decades, since it affects high-order spatial cognition even thought consisting of low-level visuo-motor processes. Objectives Despite a huge literature on this procedure, the basic neural processes related to PA and…
From experiencing sites of past to the future of the Demolition Man and how graffiti fits to all
2019
This paper explores the possibilities graffiti can provide to research user experience, focusing in those that might emerge in urban environments. The concept of User Experience (UX) can be seen as a consciously experienced phenomenon entailing for example biological, psychological and cultural, spatial and temporal aspects. Graffiti can be used as a tool to study experiences and meanings in physical and social places and practices. This can be done by studying direct experiences while completing a task, but also for example by narratives and memories involving graffiti. As the technology develops, it is incorporated in our lives, becoming more adaptive and virtual. This might have a strong…
Is addressable memory required for spatial cognition?: Poster
2021
This paper investigates the computational basis of the temporal and spatial cognition that underlies certain animal behaviours. For example, ants, when they find food, are able to encode the compass direction which takes them back to their nest. In their (2009) book, Memory and the Computational Brain (MCB), Gallistel and King articulate a classicist view: animals must do this using a symbolic, addressable, read-write memory. Here we challenge this view, arguing that complex behaviour can be explained by computational mechanisms which do not need to look like addressable random-access memory.