Search results for "Genetic Structures"
showing 10 items of 2107 documents
Bilateral maculopathy after exposure to a laser pointer: Optical coherence tomography angiography findings.
2018
Abstract Case report A 36-year-old man went to the emergency department the day after exposure to a laser pointer. Funduscopy revealed dispersed macular pigment alterations, and optical coherence tomography showed a disruption of the retinal layers. The visual acuity was counting fingers in both eyes. Nine months later, optical coherence tomography angiography showed a rarefaction in the choriocapillaris vascular flow in the area of the laser injuries. Discussion The retinal layer mainly damaged by the laser injury was the retinal pigment epithelium. However, it is suggested that the laser injury could involve tissues beyond the retinal pigment epithelium, since a rarefaction of the chorioc…
Elderly adults delay proprioceptive reweighting during the anticipation of collision avoidance when standing.
2012
The ability to reweight visual and proprioceptive information is critical for maintaining postural stability in a dynamic environment. In this study, we examined whether visual anticipation of collision avoidance (AV) while standing could facilitate the down-weighting of altered proprioception in young and elderly adults. Twelve young (24.91 ± 6.44 years) and 12 elderly (74.8 ± 6.42 years) participants stood upright for 180 s under two task conditions: (a) quiet stance (QS) and (b) standing while anticipating virtual objects to be avoided. In order to disrupt the accuracy of proprioceptive input participants were exposed to bilateral Achilles tendon vibration during the middle 60 s of stand…
Prevalence of dyslipidemia and associated risk factors in Turkish adults.
2013
Background and Objectives Dyslipidemia is a modifiable major risk factor for coronary heart disease. The objective of this study was to determine the prevalence of dyslipidemia among Turkish adults and its associations with other cardiovascular risk factors. Methods This study included 4309 people ages 20 to 83 years old from 7 provinces of Turkey. People from the city centers, districts, and villages were selected by a stratified sampling method. Weight, height, and waist and hip circumferences were measured. Blood samples were obtained to determine glucose, total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), and triglycerides …
The effect of visual focus on spatio-temporal and kinematic parameters of treadmill running
2017
The characteristics of a treadmill and the environment where it is based could influence the user’s gaze and have an effect on their running kinematics and lower limb impacts. The aim of this study was to identify the effect of visual focus on spatio-temporal parameters and lower limb kinematics during treadmill running. Twenty six experienced runners ran at 3.33 m s−1 on a treadmill under two visual conditions, either looking ahead at a wall or looking down at the treadmill visual display. Spatio-temporal parameters, impact accelerations of the head and tibia, and knee and ankle kinematics were measured for the final 15 s of a 90 s bout of running under each condition. At the end of the te…
Vision evaluation in people with Down's syndrome.
1994
We tested the colour vision of 72 people with Down's syndrome using the Ishihara test and an anomaloscope. We found that 13 of the subjects, 6 males and 7 females, had defective colour vision according to Pickford's classification. In monocular vision 10 eyes were protan (five simple, three extreme and two deviant), one eye was simple deuteranomalous and the remaining eyes were normal: in binocular vision four of the subjects were protan (two simple and two deviant), two subjects were deutan (one simple and one deviant) and the rest were normal. Many of our subjects had lens opacities, strabismus, nystagmus, hypermetropia, high myopia and astigmatism, confirming literature reports. The cont…
Upper and lower face apraxia: role of the right hemisphere.
2000
The aim of this study was to evaluate face apraxia in left- and right-hemisphere-damaged patients both in the acute and chronic stage of their disease. Two newly devised tests that assess movements of the upper and lower face districts were employed. On the whole, the proportion of left-hemisphere-damaged patients showing face apraxia were 46 and 68% for upper and lower face, respectively. A substantial proportion of right-hemisphere-damaged patients also showed face apraxia, i.e. 44% upper face and 38% lower face. Concomitant variables such as general severity, locus of lesion, language or visuo-spatial impairments, presence of neglect, interval from stroke, peculiarity of clusters of item…
Inter-hemispheric remapping between arm proprioception and vision of the hand is disrupted by single pulse TMS on the left parietal cortex.
2013
International audience; Parietal cortical areas are involved in sensori-motor transformations for their respective contralateral hemifield/body. When arms of the subjects are crossed while their gaze is fixed straight ahead, vision of the hand is processed by the hemisphere ipsilateral to the arm position and proprioception of the arm by the contralateral hemisphere. It induces interhemispheric transfer and remapping. Our objective was to investigate whether a single pulse TMS applied to the left parietal cortical area would disturb interhemispheric remapping in a similar case, and would increase a simple reaction time (RT) with respect to a control single pulse TMS applied to the frontal c…
Behavioral and event-related potential distraction effects with regularly occurring auditory deviants
2007
When auditory stimulation contains infrequent task-irrelevant changes (deviants), behavioral responses to task-relevant aspects of the stimulation are prolonged. Event-related brain potentials (ERPs) show that deviants elicit mismatch negativity (MMN), P3a, and reorienting negativity (RON). Here, we examine whether distraction effects can also be elicited within fixed auditory sequences with deviant probabilities of 0.25, 0.33, and 0.5. Deviants varied either in pitch, loudness, or sound source location. In all conditions MMN and P3a were elicited, suggesting that an automatic detection of and an attentional allocation to the change occurred. With relative frequencies of 25% and 33%, devian…
Imaging the visual autokinetic illusion with fMRI
2005
During fixation of a stationary, dim light-emitting diode (LED) in complete darkness, a subtle, apparent motion is perceived which is called autokinesis. This autokinetic illusion increases with increasing fixation time. Eleven healthy subjects were examined by fMRI while fixating an LED in darkness for 35 s. BOLD signal changes of the first and the second half of the fixation period were compared. While the stimulus was the same for both periods, perception differed in that autokinesis was more pronounced in the second half. This second half of the period was associated with bilateral activations in the motion-sensitive middle occipito-temporal area known as MT/V5. Our finding suggests tha…
Response repetition vs. response change modulates behavioral and electrophysiological effects of distraction
2004
If stimulation occasionally contains distracting information, behavioral responses to task-relevant aspects of the stimulation are prolonged and more error prone. Additionally, event-related potentials (ERPs) acquired in an auditory distraction paradigm show that the distracting information elicits the components mismatch negativity (MMN), P3a and reorienting negativity (RON). Here, we assess to what extent sequential dependencies in the stimulation influence such indicators of distraction. Data of four experiments were reanalyzed for response repetition and response change trials separately. Behavioral performance on Deviants suggests markedly smaller distraction effects in change compared…