Search Results
Results 401 - 450 of 1100
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Kiorpes Lynne - - 2003
To explore the factors limiting the development of visual sensitivity, we constructed an ideal observer model for the infant macaque visual system. We made measurements of retinal morphology in infant and adult macaque monkeys, and used the data in combination with published optical data to formulate the model. We compared ...
Hunter Sharon K - - 2003
This study examined the effect of attention in young infants on the saccadic localization of peripheral stimuli. Infants ranging in age from 5 to 14 weeks were tested using a peripheral stimulus detection paradigm. The presence of a central fixation stimulus decreased detection probability, particularly if attention was engaged with ...
Teller Davida Y - - 2003
When infants fail to make chromatic discriminations, do the characteristics of their performance minima coincide more closely with the properties of adult luminance matches or heterochromatic brightness matches? In addition to their spectral properties, adult luminance matches are typically characterized by relatively small individual differences, whereas brightness matches are believed ...
Claflin Dragana I - - 2002
Associative learning was evaluated in human infants with simple delay classical eyeblink conditioning. A tone conditioned stimulus (CS) was paired with an airpuff unconditioned stimulus (US) at three different delay intervals (250, 650, and 1,250 ms). Independent groups of healthy, full-term 5-month-old human infants were assigned to these three paired ...
Konishi Yukuo - - 2002
We performed functional magnetic resonance imaging and optical topography over the visual cortex of subjects during sedation with pentobarbital, and 8-Hz flickering light was intermittently projected onto their eyelids. Two age groups were analyzed: infants <60 days old and those >60 days old (corrected for gestational age at birth). The ...
Fiser József - - 2002
The ability of humans to recognize a nearly unlimited number of unique visual objects must be based on a robust and efficient learning mechanism that extracts complex visual features from the environment. To determine whether statistically optimal representations of scenes are formed during early development, we used a habituation paradigm ...
Wang Vivian M - - 2002
BACKGROUND: Cataracts pose a serious threat to the visual system in infants and children, requiring prompt surgical intervention and rehabilitation to optimize visual development. Glaucoma is a serious complication following cataract surgery in infants and can lead to loss of vision. Early diagnosis of glaucoma, however, can be quite challenging ...
Suttle Catherine M - - 2002
Young infants can distinguish red from green without brightness cues which shows that neural pathways processing color information (the 'red-green' color-opponent pathway) are functional early in life. There is some doubt over whether the 'blue-yellow' pathway is functional in young infants. Here, we show that infants behave like tritanopic adults ...
Kushnerenko Elena - - 2002
Mismatch negativity (MMN) is a negative component of auditory event-related potential (ERP), reflecting the brain's automatic change detection process. In the present study we investigated the development of the pitch change detection, as indexed by the MMN, in the same infants from birth until 12 months of age. The MMN ...
Turner J E - - 2002
This study investigated the development of the link from accommodation to vergence in infants by occluding one eye thus removing binocular cues. Occluded adults continue to converge partially demonstrating that the accommodative drive to vergence (the AC/A link) and proximal cues are sufficient to drive vergence. For infants of all ...
Krasevec Julia M - - 2002
BACKGROUND: Adequate intake of essential fatty acids (EFAs) is required for optimal development of the central nervous system and visual acuity in infants. Little information exists regarding the EFA status of vulnerable populations living in Southern regions. OBJECTIVE: We examined the adequacy of EFA status in Cuban breast-feeding mothers and ...
Cacho Pilar - - 2002
PURPOSE: To determine which are the most sensitive tests, together with accommodative amplitude, to classify accommodative insufficiency (Al), we analyzed the relation between monocular estimated method (MEM) dynamic retinoscopy, monocular and binocular accommodative facility (MAF, BAF), and positive relative accommodation (PRA) with or without the presence of reduced amplitude of ...
Colombo John - - 2002
Four-month-old infants were exposed to sequences in which a 2-s light stimulus alternated with dark interstimulus periods whose length was manipulated to be 3 or 5 s. A predictable on-off pattern occurred for eight trials, but the light stimulus was omitted on the ninth trial. Infants showed heart rate responses ...
Lavoie Chantale - - 2002
Using a new polynomial regression criterion, the authors investigated empirically the short-term reliability of infants' visual habituation measures. Twenty-one 5-month-old infants were tested twice with a 1-day interval. Results revealed many reliable habituation measures, a reliable reaction to novelty measure, and a new reliable measure of interest. The 2nd-order polynomial ...
Delgado Christine E F - - 2002
This study examined the importance of target location (within vs. outside the visual field) on the relation between responding to joint attention and subsequent language development in 47 normally developing infants. The results supported a developmental progression in the infants' ability to locate targets from within to outside the visual ...
Revilla Isabel - - 2002
The aim of the present work was to study the effect of both vintage and the use of four types of pectinolytic enzymatic preparations on the quality of red wine using factor analysis. We also studied the evolution of the factors obtained along two years of storage of the wine. ...
Dibiasi Jasmin - - 2002
BACKGROUND: The assessment of the quality of general movements (GMs) in infants proves to be a reliable and valid diagnostic tool for detecting brain dysfunction early in life. Of special interest, particularly for the prediction of cerebral palsy, is the fidgety kind of GMs, the so-called fidgety movements (FMs) observable ...
Chiu Bill - - 2002
Periodic alternating nystagmus is a rare central nervous system disorder in which the eyes undergo a horizontal jerk nystagmus that periodically reverses direction. A patient with a hypoplastic cerebellum and enlarged cisterna magna exhibited transient periodic alternating nystagmus following an attack of Ménière's disease. We hypothesize that in susceptible individuals ...
Schulz Elisabeth - - 2002
PURPOSE: To investigate the effect of field size on grating acuity assessment in normal children and pediatric ophthalmological patients. METHOD: A prototype set of acuity cards was produced with three acuity steps per octave and a card size of 26 x 70 cm, bearing a grating field of 26 x ...
Malcolm C A - - 2002
This paper investigates gender differences in the peak latency and amplitude of the P1 component of the pattern-reversal visual evoked potential (pattern-reversal VEP) recorded in healthy term infants. Pattern-reversal VEPs in response to a series of high contrast black and white checks (check widths 120', 60', 30', 24', 12', 6') ...
Koura Takahiro - - 2002
BACKGROUND: Anisotropic conduction properties may provide a substrate for reentrant arrhythmias. We investigated the age-dependent changes of structural and functional anisotropy in isolated right atria from infant (1 to 2 months), young (6 to 12 months), and old (6 to 10 years) dogs. METHODS AND RESULTS: The histology of the ...
Cavallini Anna - - 2002
Teller Acuity Cards are a new "preferential looking" procedure for the evaluation of visual acuity in newborns and infants. We used this test to assess, longitudinally, visual acuity in 60 healthy term newborns followed up from birth to two years of age. In order to have a set of comparison ...
Adams Russell J - - 2002
Despite the emerging scientific and clinical importance of measuring human contrast sensitivity (CS), developmental data are sparse, especially those obtained with a single methodology. We used a new, time-efficient, psychophysical card procedure to evaluate binocular CS in groups of 20 4- to 9-yr-olds and 10 adults. Combined with data from ...
Collins Michael J - - 2002
BACKGROUND: Correction of infant aphakia with conventional soft and rigid designs induces significant amounts of positive spherical aberration. METHODS: Different levels of positive spherical aberration were induced by rigid lenses positioned close to the eye. Visual acuity and depth of focus were measured for twelve young adult subjects. RESULTS: Positive ...
Leibold Lori J LJ Department of Speech and Hearing Sciences, University of Washington, Seattle 98105-6246, - - 2002
Reaction time (RT) to sound is known to be related to loudness in adult listeners. The purpose of this study was to determine whether infants' RT to sound decreases systematically with intensity as it does in adults. RT was measured for 24 6- to 9-mo-old infants and 11 19- to ...
Richards John E JE Department of Psychology, University of South Carolina, Columbia, SC 29208, - - 2002
Several models of the development of infant visual attention have used information about neural development. Most of these models have been based on nonhuman animal studies and have relied on indirect measures of neural development in human infants. This article discusses methods for studying a "neurodevelopmental" model of infant visual ...
Szundi Istvan - - 2002
Absorbance difference spectra were recorded at 20 degrees C from 30 ns to milliseconds after photolysis of lauryl maltoside suspensions of artificial visual pigments derived from 9-cis isomers of 5-ethylretinal, 8,16-methanoretinal (a 6-s-trans-bicyclic analogue), or 5-demethyl-8-methylretinal. In all three pigments, the earliest intermediate that was detected had the characteristics of ...
Plager David A - - 2002
PURPOSE: The optimal role of intraocular lenses (IOLs) in infants remains a controversial topic for many reasons, including concerns about significant complications occurring in young rapidly developing eyes. METHODS: To assess the number and type of significant complications requiring further intervention occurring in the first postoperative year, we reviewed the ...
Brown K A - - 2002
Identification of thoracoabdominal asynchrony (TAS) during breathing is currently detected by visual coding of records of ribcage (RC) and abdominal (AB) movements. There is thus a need to automate this process in order to save time and improve TAS detection accuracy. We studied 15 infants of 39-49 weeks postconceptional age. ...
O'Connor Anna R - - 2002
OBJECTIVE: A prospective study of retinopathy of prematurity (ROP) of 505 infants who weighed <1701 g at birth was undertaken in the mid-1980s. This cohort was traced at 10 to 12 years of age to determine how low birth weight alone and ROP might influence their ophthalmic outcome. METHODS: Outcome ...
van Wezel-Meijler G - - 2002
AIM: To study the influence of dietary-supplied long-chain polyunsaturated fatty acids on structural brain maturation in preterm infants and to investigate parameters of functional brain development, relating them to structural maturation. Other studies have suggested that dietary supplementation of long-chain polyunsaturated fatty acids in preterm infants may enhance their visual ...
Repka Michael X - - 2002
Preterm infants are more likely than term infants to have significant abnormalities of all parts of the visual system leading to reduced vision. The most common problem is retinopathy of prematurity (ROP). The frequency and severity of this disorder is inversely related to gestational age. Damage ranges from minor to ...
Atkinson J - - 2002
OBJECTIVES: To compare the age of onset of the pattern orientation reversal visual evoked potential (OR-VEP) in a group of very low birthweight (VLBW) premature infants with term infants matched for postconceptual age at testing. The OR-VEP measure is used as an indicator of visual cortical functioning because of the ...
Feuer William J - - 2002
PURPOSE: To determine the reproducibility over time of visual estimates of the horizontal cup/disk ratio by trained technicians from optic disk stereophotographs. METHODS: Baseline optic disk stereophotographs are graded at entry and regraded annually in a masked fashion. The 1,636 participants in the Ocular Hypertension Treatment Study (OHTS) undergo stereoscopic ...
Cheour Marie - - 2002
Event-related brain potentials of 10 full-term newborns in response to duration changes in complex, harmonic tones known to elicit prominent mismatch negativity (MMN) response in adults were investigated. Here we report that duration changes elicited prominent MMN responses in a 11 newborns tested. In contrast, MMN has been reported in ...
Rose Susan A - - 2002
Developmental change and stability of visual expectation and reaction times (RT) were examined at 5, 7, and 12 months in a longitudinal sample of term and preterm infants (birthweight <1,750 g). Using the traditional 200-ms cut-point to separate anticipatory from reactive saccades, RTs (and their standard deviations) declined markedly over ...
Birch E E - - 2001
Visual impairment, oculomotor abnormalities, and refractive error are prevalent among children with a history of preterm birth. These conditions may result from exposure of the immature visual system to early visual stimulation, from nutritional deficits that occur following the abrupt loss of placental maternal-to-fetal transfer of essential nutrients, and as ...
Wilk A E - - 2001
In three experiments with sixty 3- and 6-month-olds, we examined whether operant and visual-preference measures of retention are equivalent. Infants learned to move a mobile by kicking and then received a paired-comparison test with the familiar (training) mobile and a novel one. Kicking above baseline was the direct measure of ...
Shiuey Y - - 2001
Endokeratoplasty using an infant donor cornea was performed in an 81-year-old man with Fuchs' endothelial dystrophy, corneal decompensation, and a history of cystoid macular edema in the left eye. The patient reported minimal discomfort after surgery, and the best spectacle-corrected visual acuity improved from 20/400 to 20/100 by the second ...
Suttle Catherine M - - 2001
The accurate and reliable assessment of visual function in infants and young children is important for ensuring optimal management of those at risk of abnormal visual development. Visual acuity is the aspect of visual function most commonly assessed by optometrists and can be measured in infants and children using appropriate ...
Horwood A M - - 2001
PURPOSE: A remote haploscopic photorefractor, designed for assessment of accommodation and convergence in infants and clinical groups, was used to determine heterophoria accommodative convergence/accommodation (AC/A) ratios in normal naïve adults. These were compared with conventional clinical measures. METHODS: Twenty-one naïve subjects were used to compare occluded and unoccluded prism cover ...
Weiss A H - - 2001
OBJECTIVE: To further explain cortical abnormalities in infants without visually guided behaviors with anatomically normal eyes by using a battery of objective visual tests and neuroimaging studies. DESIGN: A cohort study. PARTICIPANTS: Thirty-one infants with clear ocular media and normal fundi, who were visually unresponsive by clinical examination, and 31 ...
Da Pozzo S - - 2001
AIMS: To report 6 cases in which indocyanine green angiography (ICGA) failed to convert occult choroidal neovascularization (CNV) into well-defined CNV in adult-onset foveomacular vitelliform dystrophy (AOFVD). METHODS: Patients with AOFVD observed from 1993 to 1999 were prospectively followed up. Whenever the development of CNV was suspected, ICGA was performed ...
Innis S M - - 2001
OBJECTIVE: To determine whether docosahexaenoic acid (DHA) is related to visual and neural development in term breast-fed infants. DESIGN: A prospective study of 83 infants who were exclusively breast-fed for at least 3 months. We determined red blood cell and plasma fatty acids at 2 months, visual acuity at 2, ...
Calloway S L - - 2001
PURPOSE: To clinically evaluate the random dot stereoacuity cards developed by Birch and Salomao on a population of infants within the first 12 months of life and to generate baseline normative data. METHODS: Random dot stereoacuity cards were constructed using vectographic vertical bar stimuli with cross disparities ranging from 45 ...
Comer R M - - 2001
PURPOSE: To analyze graft survival and visual outcome after penetrating keratoplasty in infants with congenital corneal opacity. METHODS: We retrospectively reviewed the records of 11 patients with congenital corneal opacity who underwent penetrating keratoplasty as infants. Six patients had a diagnosis of Peter's anomaly, 1 of congenital hereditary endothelial dystrophy, ...
Makrides M - - 2001
Visual-evoked potential (VEP) acuity has been used to assess the effects of dietary fats on the integrity of the visual pathway of infants. We investigated prognostic determinants of VEP acuity at 16 wk of age. The results of two randomized dietary intervention trials designed to assess the effect of dietary ...
Bacher L F - - 2001
Fluctuations in body movement and visual inspection were measured over minutes in 3-month-old infants to look for evidence of coupling. In Experiment 1, infants (n = 12) looked ad libitum at two identical pictures for an average of 7.3 min. Analysis of the spontaneous fluctuations in movement and inspection revealed ...
Young Y H - - 2001
OBJECTIVE/HYPOTHESIS: Downbeat nystagmus is defined as spontaneous nystagmus present with fixation in the primary position or lateral gaze. Those who have downbeat nystagmus but negative magnetic resonance imaging results are termed as idiopathic. Patients with idiopathic downbeat nystagmus, although unconcerned with their etiology, have visual symptoms such as oscillopsia, diplopia, ...
Sie LTL - - 2001
Functional MRI (fMRI) of the visual cortex was evaluated in 42 sedated 18-month-old infants (mean corrected age; 31 males, 11 females) with or without periventricular leukomalacia (PVL). Data from 14 infants could not be evaluated because of movement artefacts. Ten of the remaining 28 infants showed no significant fMRI response ...
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