Search results for "visio"
showing 10 items of 5207 documents
fMRI signal increases and decreases in cortical areas during small-field optokinetic stimulation and central fixation
2001
Small-field optokinetic nystagmus (OKN) was performed in seven healthy volunteers in order to analyze the activation and deactivation patterns of visual motion, ocular motor, and multisensory vestibular cortex areas by means of fMRI during coherent visual motion stimulation. BOLD signal decreases (deactivations) were found in the first and second long insular gyri and retroinsular areas (the human homologue of the parietoinsular vestibular cortex and the visual posterior sylvian area in the monkey) of both hemispheres, extending into the transverse temporal gyrus and inferior-anterior parts of the superior temporal gyrus (BA 22), and the precentral gyri at two separate sites (BA 4 and 6). F…
Blue-yellow deficiency in workers exposed to low concentrations of organic solvents
1997
Objectives: To evaluate the effects of low concentrations of organic solvents on color vision. Methods: Color vision was examined in 24 workers exposed to mixtures of solvents and in 24 control subjects. Exposure to mixtures was below the threshold-limit values. Color vision ability was assessed using the Ishihara plates (to screen for congenital dyschromatopsia), the Farnsworth panel D-15 test, the Lanthony desaturated panel D-15 test, and the Standard Pseudoisochromatic Plates part 2 (SPP2 test). Results: The comparatively less sensitive Farnsworth panel D-15 test failed to show any difference between the groups, but the Lanthony panel D-15 desaturated test as well as the SPP2 test showed…
Characterization of Small Incidental Indeterminate Hypoattenuating Hepatic Lesions: Added Value of Single-Phase Contrast-Enhanced Dual-Energy CT Mate…
2018
OBJECTIVE. The objective of this study is to determine whether single-phase contrast-enhanced dual-energy CT (DECT) material attenuation analysis improves the characterization of small (< 2.0 cm) incidental indeterminate hypoattenuating hepatic lesions, compared with conventional single-energy CT evaluation. MATERIALS AND METHODS. This retrospective study involved 55 patients (24 men and 31 women; mean [± SD] age, 63.9 ± 15.3 years) with 77 incidental hypoattenuating hepatic lesions (59 benign and 18 malignant lesions) measuring 0.5–2.0 cm who underwent single-phase contrast-enhanced DECT of the abdomen for pain. For each lesion, attenuation measurements were obtained using blended 120-k…
Does viotin activate violin more than viocin? On the use of visual cues during visual-word recognition.
2013
The vast majority of neural and computational models of visual-word recognition assume that lexical access is achieved via the activation of abstract letter identities. Thus, a word’s overall shape should play no role in this process. In the present lexical decision experiment, we compared word-like pseudowords like viotín (same shape as its base word: violín) vs. viocín (different shape) in mature (college-aged skilled readers), immature (normally reading children), and immature/impaired (young readers with developmental dyslexia) word-recognition systems. Results revealed similar response times (and error rates) to consistent-shape and inconsistent-shape pseudowords for both adult skille…
Preattentive and attentive responses to changes in small numerosities of tones in adult humans
2016
The brain hosts a primitive number sense to non-symbolically represent numerosities of objects or events. Small exact numerosities (~4 or less) can be individuated in parallel. In contrast, large numerosities (more than ~4) can only be approximated. However, whether small numerosities can be approximated without their parallel individuation remains unclear. Parallel individuation is suggested to be an attentive process and numerical approximation an automatic process. We, therefore, tested whether small numerosities can be represented preattentively. We recorded adult humans׳ event-related potentials (ERPs) and behavioral responses to 300-ms sequences of six tones (each of either 440 Hz or …
Diseño de una nueva prueba para medir la función de sensibilidad al contraste con iPad
2015
[EN] Purpose: To introduce a new application (ClinicCSF) to measure Contrast Sensitivity Function (CSF) with tablet devices, and to compare it against the Functional Acuity Contrast Test (FACT). Methods: A total of 42 subjects were arranged in two groups of 21 individuals. Different versions of the ClinicCSF (.v1 and .v2) were used to measure the CSF of each group with the same iPad and the results were compared with those measured with the FACT. The agreements between ClinicCSF and FACT for spatial frequencies of 3, 6, 12 and 18 cycles per degree (cpd) were represented by Bland---Altman plots. Results: Statistically significant differences in CSF of both groups were found due to the change…
Recombinant human granulocyte-macrophage colony-stimulating factor induces secretion of autoinhibitory monokines by U-937 cells
1988
Colony-stimulating factors are required for survival proliferation, differentiation and functional activation of granulocytes, macrophages and their precursor cells. In the present report, however, we demonstrate antiproliferative activity of recombinant human (rh) granulocyte-macrophage colony-stimulating factor (GM-CSF) on monoblast cell line U-937 and provide evidence for the involvement of tumor necrosis factor alpha TNF-alpha and interleukin 1 beta (IL 1 beta) in its growth inhibitory action. GM-CSF (but not granulocyte CSF, G-CSF or macrophage CSF, M-CSF) suppressed DNA synthesis and self renewal of U-937 cells. Similarly, medium conditioned by U-937 cells in response to GM-CSF (GM-CS…
Multichannel functional testing in normal subjects, glaucoma suspects, and glaucoma patients
2012
Purpose.: To evaluate visual function with a novel multichannel functional test named the ATD Multichannel Functional Test. Methods.: This multicenter study had a prospective and cross-sectional design. A total of 186 eyes were included: 42 with glaucoma, 14 glaucoma suspects due to optic nerve characteristics, 25 ocular hypertensives, and 105 normal eyes. All patients performed standard visual fields (Humphrey 24-2) and ATD with eight stimuli configurations: four achromatic (A), two red-green (T), and two blue-yellow (D). To derive main outcome measures, mean sensitivity, mean defect (MD), and pattern standard deviation (PSD) were calculated and compared among groups and types of stimuli w…
Acute effects of transient vertical whole-body vibration
1991
The question as to whether shock-type whole-body vibration causes increasingly acute strain was investigated. Random vibrations were superimposed with shocks differing in amplitude and in number per unit of time in a systematic manner. The weighted root mean square (rms) acceleration was kept constant in all over the varied experiments. A total of 17 men were exposed to vibration from an electrohydraulic simulator. The following strain criteria were used: biodynamic behavior of the trunk and the head, electrical activity of the muscles of the back and the neck, subjective sensation, skin temperature in the lumbar area and visual and tracking performance. It was found that increasing shock a…
Characterisation of focal liver lesions undetermined at grey-scale US: contrast-enhanced US versus 64-row MDCT and MRI with liver-specific contrast a…
2010
The aim of this study was to assess the role of contrast-enhanced ultrasonography (CEUS) in the characterisation of focal liver lesions in comparison with multidetector computed tomography (MDCT) and magnetic resonance imaging (MRI) with liver-specific contrast agent.One hundred and eighty-seven focal liver lesions, 91 malignant and 96 benign (mean size 3.2 cm) - proved by biopsy (n=12), histology (n=4), MDCT (n=108), MRI (n=44) MDCT/MRI (n=19) - in 159 patients were studied by CEUS. Two expert radiologists consensually evaluated the contrast-enhancement patterns at CEUS. For each lesion, they assessed: (a) nature (benign, malignant, not assessable), (b) specific diagnosis and (c) need for …