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Birch E E - - 1983
The onset of measurable stereopsis in human infants occurs at approximately 4 months of age, directly following a period of rapid oculomotor development. The experiment reported here was designed to investigate whether the onset of stereopsis is determined solely by the onset of accurate oculomotor coordination or whether neural development ...
Dobson V - - 1983
Photorefraction was used to assess the state of accommodation of 3-month old infants with and without astigmatism while they viewed stimuli in an apparatus commonly used to test infant visual acuity. The stimuli were a 1.6 c/deg vertical grating, a 1.6 c/deg horizontal grating and a cross composed of orthogonal ...
Atkinson J - - 1983
Contrast sensitivity for a 3 cycles deg-1 sinusoidal grating in 7-10 month old infants was tested by presenting gratings and uniform fields on cylinders, with the former providing auditory reinforcement when the infant picked them up. The method shows that a contrast as low as 7.5% can commonly be detected ...
Dannemiller J L - - 1983
Increment threshold functions were measured from -4.0 to 1.2 log cd/m2 in 7-12-week-old infants using a behavioral forced-choice paradigm. The slopes of the infant functions were considerably shallower than the slopes of adult functions over the same luminance range. The value of the infant slope increased rapidly between 7 and ...
Braddick O - - 1983
Visual evoked potentials (VEP) elicited by a dynamic random-dot correlogram were used to assess the development of cortical binocular function in infant subjects. In a group of newborn infants who showed a VEP for a comparable non-binocular stimulus, none showed evidence of binocular function. A further group of infants were ...
Morante A - - 1982
Pattern preference for four different pairs of patterns, and visual acuity based on the ability to distinguish black and white stripes of different widths, were compared in neurologically normal and abnormal preterm infants at 36 and 40 weeks postmenstrual age and in normal and abnormal fullterm infants in the newborn ...
Kaga M - - 1982
The auditory brainstem response (ABR) was studied in an infant with Gaucher's disease. The infant was normal until the age of three months. His illness began with stridor, strabismus, inguinal hernia and failure to thrive. Thereafter, muscular rigidity with opisthotonus, ocular palsies, difficulty in swallowing and respiratory failure due to ...
Koenig S - - 1982
Five adult patients underwent penetrating keratoplasty in which corneal tissue from donors 3 months old or younger was used. In each case, a large myopic shift in refraction was found after surgery (mean, 9 diopters). The average postoperative spherical equivalent was -7.35 diopters. This resulted from the extremely steep curvature ...
Mendelson M J - - 1982
4-month-old infants were presented a 60-sec recording of a syllable repeated in either a regular or an irregular rhythm. The rhythms contained the same time intervals, but the pattern of the intervals differed. Following the sound, the infants were shown a 90-sec silent film of a puppet opening and closing ...
Birnholz J C - - 1982
The cerebellum can be visualized ultrasonically in preterm and full-term newborn infants. A cross-sectional area measurement of the central portion of the vermis correlated with gestational age (r = .98) when growth was normal (N = 51). Central vermian area was decreased in small-for-date newborn infants (N = 10) but ...
Andrews P L - - 1982
1. The compound action potential was recorded in segments of posterior abdominal vagus removed from patients undergoing elective vagotomy and the conduction velocities of the major components were measured. 2. The conduction velocities ranged from 0.15 m/s to 3.9 m/s. The majority of compound potentials recorded had latencies appropriate to ...
Crozier G - - 1982
Retrolental fibroplasia (RLF) remains as a leading cause of visual impairment in infants. The pathophysiology of RLF is discussed as well as the significant risk factors. The clinical course of the disease is considered including the various stages of RLF and the differential diagnosis. Finally, the management and treatment options ...
MacKay-Soroka S - - 1982
The present study investigated the effect of the relation between conditions at encoding and retrieval on infants' performance on a paired-comparison recognition test. 64 9-month-old infants were given 40 sec to visually or visually and haptically explore a 3-dimensional object. Subsequently, during a 10-sec recognition trial infants were presented with ...
Merritt J C - - 1982
Ten infants (18 eyes) blind from stage V cicatricial retrolental fibroplasia were examined from January 1978 to January 1981 at North Carolina Memorial Hospital. The early perinatal factors which may have predisposed to the binding end-stage cicatrix are identified. To increase their visual potential and to prevent secondary angle closure ...
Atkinson J - - 1982
A method is described for obtaining rapid and reliable estimates of acuity in infants, for both monocular and binocular viewing. The method depends on 'preferential looking', where the infant prefers to look at a striped pattern rather than a blank screen of matched mean luminance. A staircase procedure for testing ...
Rubinstein A - - 1982
Recording the response of the auditory nerve (W1) in neonates can contribute to the diagnostic distinction between audiological-otological versus neurological pathology. If W1 latency were subject to relatively rapid shortening in the hours directly after birth, inconsistencies in the literature might be clarified. The purpose of this research was to ...
Mitchell M - - 1982
A modification of Cohen's (1973) method was used to study responses to patterns of varying complexity in 4-mo.-old infants. Complexity in this context was defined in terms of the number of elements and the degree of internal contour contained in a given pattern. The infants were first presented with small ...
Jacobson S G - - 1982
We tested the visual acuities of 110 infants with ocular disorders by a preferential-looking technique that provides fast, accurate measurements for preverbal children. The results were used to confirm initial clinical evaluations and to prescribe and monitor treatment. The test was particularly helpful in assessing the effects of occlusion therapy. ...
Boothe R G - - 1983
Infants have much poorer acuity than adults. Recent experiments with infant monkeys indicate that this poor acuity cannot be explained on the basis of optics (quality of the retinal image) or sampling frequency (inter-receptor spacing). On the other hand, the poor acuity is not just a reflection of immature cognitive ...
Teller D Y - - 1983
Infants as young as 1 month postnatal have scotopic spectral sensitivity closely resembling the CIE standard curve and thus appear to have a functional, rhodopsin-based rod system. Neutrally adapted photopic spectral sensitivities are broad and roughly equal to those of adults tested under similar conditions, although infants may show an ...
Birch E E - - 1982
The development of stereoacuity for crossed and uncrossed disparities was assessed by means of a preferential looking procedure in a cross-sectional sample of infants aged 2-12 months and by following a longitudinal sample over the first 8 months of life. Crossed stereoacuity was found to develop earlier but at approximately ...
Banks M S - - 1983
This paper reviews work on the development of spatial and temporal contrast sensitivity in human infants. Both electrophysiological and behavioral techniques have been used. Infants' spatial contrast sensitivity functions exhibit a large deficit in spatial resolution and overall contrast sensitivity relative to adult functions. These measurements also reveal continuous development ...
Powers M K - - 1982
Recent theoretical arguments (Green et al. (1980) Vision Res. 20, 827-835) predict that young human infants should have large depths of focus compared to adults. If so, optical blur should have relatively little effect on the resolving power of infant subjects. We tested this hypothesis by measuring the influence of ...
George L - - 1982
Echocardiography has previously been of limited use in visualizing the aorta in neonates and infants. Using a new technique--right parasternal scanning--the aortic arch and brachiocephalic vessels were studied in 50 children under 18 months of age. Complete visualization was accomplished in 47 patients including those 1) under 1,000 grams, 2) ...
Finlay D - - 1982
A technique of monocular eye patching was used to measure the response of infants three and four months old to nasally and temporally placed stimuli at various eccentricities in the visual field. The results indicated a field of field of binocular overlap of approximately 60 deg in infants three months ...
Naegele J R - - 1982
Monocular optokinetic nystagmus (OKN) was studied in 24 human infants aged 3-35 weeks using electro-oculography and moving vertical gratings. At a constant velocity of 25 deg/sec, infants display direction dependent slow phase asymmetries until approximately 5 months after birth. A comparison was made of the cumulative eye displacement during the ...
Hoyt C S - - 1982
In recent years, the ophthalmic examination of infants has been of increasing interest to both clinicians and vision researchers. Clinicians have documented a greater risk of retinopathy, strabismus and amblyopia in premature infants, especially those of low birthweight. In addition to the external and retinal examination of the infant eye, ...
Banks M S - - 1982
Human infants' contrast thresholds for rectangular wave gratings differing in duty cycle were measured. The forced-choice preferential looking technique was used to estimate thresholds in fifteen 8- to 10-week old infants. The results indicated that contrast threshold varied systematically with duty cycle. Our findings were consistent with the predictions of ...
Gottfried A W - - 1981
Infants in newborn intensive and convalescent care units are exposed to large amounts of sensory stimulation of various sorts. Although infants in these units do not lack visual, auditory, and tactile stimulation, they receive relatively infrequent coordinated sensory experiences. Furthermore, there is no diurnal rhythmicity in physical and social stimulation ...
Jacobson S G - - 1981
The visual acuity of 4 infants with congenital cataracts was measured serially during the first year of life by a preferential looking technique. Two infants with bilateral cataracts and no measurable acuity before surgery showed rapid development of acuity to normal levels for age after surgery and optical correction. In ...
Schexnider V Y - - 1981
Human and geometric forms were presented to 12-month-old male infants to determine if those with a large number of minor physical anomalies would show different habituation than infants with a small number. Results from a procedure using human forms in a random order failed to yield differences, but differences in ...
Lewkowicz D J - - 1981
The present study investigated intersensory interaction between auditory and visual stimulation in newborn infants. Stimulation in 1 modality may influence the response to stimulation in a second modality by changing the infant's state of arousal. To test this possibility, newborns' visual preferences for light patches of different intensity were examined ...
Hack M - - 1981
To demonstrate the presence of discriminable awake states in preterm infants, facial behaviors and visual fixation to a single patterned stimulus were recorded. Five healthy preterm infants born at a mean of 29 weeks' gestation were followed from 30 to 35 weeks' postmenstrual age. Behaviors (eye openness, movements, mouthing, and ...
Wood T O - - 1981
A series of 13 patients who have undergone corneal transplantation with infant corneas have been reviewed. The average donor is eleven months. All grafts with infant donor material were crystal clear from the first postoperative day with no folds in Descemet's membrane. The corneas take on a normal convex shape ...
von Noorden G K - - 1981
To explore the premise that the immature primate visual system responds differently to total unilateral occlusion (no competitive abnormal binocular interaction) than it does to lid suture, one eye in two infant Macaca mulatta was completely occluded with optically opaque material. After a recovery period of 2 months, single cell ...
Fuller P W - - 1981
This study was conducted to determine whether an averaged evoked potential technique using a random-versus-repetitive presentation mode, could be used to study auditory discrimination in infants. We were interested in which stimulus mode, random-novel or repetitive, would result in greater responsiveness in terms of central nervous system evoked potential latencies ...
McDonnell P M - - 1981
This study replicated a previous demonstration of prism-induced aftereffects in 5-9-month-old infants. Aftereffects were considered to be changes in direction of reaching for visual targets following prism exposure. The present study employed a longitudinal design. In the experimental group, infants were exposed to 25-diopter lateral displacing prisms once each month ...
Rogers G L - - 1981
Seven infants with complete bilateral cataracts were operated on and fitted with extended-wear silicone contact lenses. The infants were matched to 16 normal control subjects. A modified preferential looking technique was used to assess visual acuity; the Bayley Scale of infant Development was administered to measure psychological development. Of the ...
Fulton A B - - 1981
This paper reviews the course of development of visual acuity in human infants and young children. Researchers have devised methods based on optokinetic nystagmus, visually evoked cortical potentials and preferential looking to assess visual acuity in infants and preverbal youngsters. During the first postnatal year and early childhood, acuity, measured ...
Cox C - - 1981
Brainstem-evoked response audiometry (BERA) was performed on 40 preterm infants who had low neonatal risk scores. Mean latencies for waves I and V were obtained from four age-groups, 33-34, 35-36, 37-38 and 39-40 weeks conceptional age. The results indicate that BERA is a valuable and reliable tool in assessment of ...
Hosford-Dunn H - - 1981
Short-latency evoked potentials to monaural and binaural clicks were recorded from scalp electrodes on healthy full-term neonates and on normally hearing adults. Binaural interaction (BI) was measured by summing the average monaural responses obtained from each ear (L+R) and subtracting the binaural response (B) from the monaural sum (BI=L+R-B). Consistent ...
Lasky R E - - 1980
5-month-old infants were presented visual patterns for 100 msec followed by a 100-msec patterned masker at intervals of 0, 250, 500, and 2,000 msec after the offset of the stimulus. This procedure was repeated 45 times. Only infants in the 2,000-msec stimulus-masker interval condition significantly fixated a novel stimulus longer ...
Lawson K R - - 1980
The results of this study indicate that newborn infants' fixation of a graduated series of visual stimuli comprised of a low (1), intermediate (4 or 16), and a high (64) number of cubes is significantly different in the absence and presence of sound (white-noise bursts). Relative to the no-sound condition, ...
Dobson V - - 1980
Visual acuity was screened in 36 healthy infants born 4 or more weeks prior to term. Preterm infants tested at 8 and 12 weeks of postnatal age showed significantly poorer performances than those shown by 8- and 12-week-old full-term infants. However, no differences in performance were found when the scores ...
Shea S L - - 1980
A new method for testing stereopsis in infants is described for use in the early assessment of binocular function. Four 6- and 12-month-old infants were presented with a dynamic random-element stereogram generated on a color television monitor. A stereoscopic form was moved laterally, either left or right, to elicit the ...
Salamy A - - 1980
Maturation along the brainstem acoustic pathway, as well as the integrity of these structures, has been shown to be reflected in brainstem evoked potential recordings. Trajectories formed from repeated sequential measurements of several brainstem response variables reveal distinct developmental curves for healthy and high-risk infants. Longitudinal analysis offers a means ...
Held R - - 1980
Stereograms were presented in a two-choice preference procedure. The mean age at which stereopsis was first demonstrable was 16 weeks. By a mean age of 21 weeks, infants had achieved stereoacuity of 1 minute of arc or better. In comparison with the relatively slow development of visual acuity, the time ...
Mast V K - - 1980
Infants were pretrained to move crib mobiles containing 6 or 10 identical objects by means of footkicking and were then exposed to a reinforcer containing only 2 objects. Relative to infants with no prior history of reinformcement with either of the "larger mobiles, infants shifted to the "smaller" mobile had ...
Dubowitz L M - - 1980
Visual function in the preterm newborn infant has been studied by the visual orientation (tracking) technique of the Brazelton neurobehavioural assessment, and by the pattern preference and fixation techniques of Frantz. Both these methods demonstrated the presence of discriminative visual function by 31 to 32 weeks gestation, which by 34 ...
Gwiazda J - - 1980
A simple and rapid method for assessing the visual acuity of infants can be a valuable tool for eye care specialists as well as for researchers in vision. We have developed a preferential looking (PL) procedure that uses simple equipment to obtain measures of PL acuity in a few minutes. ...
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