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Nussbaum A R - - 1986
The uterus in the neonate is prominent and readily identified on ultrasonography (US). The neonatal uterus is larger than the prepubertal uterus as a result of residual stimulation from maternal hormones. The uterus was visualized in 31 of 35 (89%) infant girls examined with real-time US. Mean uterine length was ...
Jaffe M - - 1986
This investigation tested the hypothesis that high risk infants showing immaturity in localisation of a sound stimulus would be more likely to have appreciable neurodevelopmental dysfunction. The cohort comprised 112 infants, 66 of whom were classified as 'high risk'. Every infant underwent a neurological and developmental assessment, a sound localisation ...
Cornell E H - - 1986
Measurement of duration of fixation was used to assess the ability of 6-, 12-, 24-, and 36-week-old infants to discriminate black-and-white square-wave gratings from a homogeneous gray field at a distance of 20 ft (6.1 m). Acuity was estimated as the smallest stripe width detectable by at least 18 of ...
Brown A M - - 1986
Binocular visual acuity of normal newborn infants, preterm newborn infants, and newborn, full-term infant patients with nonophthalmologic abnormalities was measured by means of grating acuity cards. Each test took about six minutes to complete, and 89% of the tests (154 of 174) were successful. Visual acuity of infants at 39 ...
Gunderson V M - - 1986
Infant crab-eating macaques exposed in utero to maternal subclinical levels of methylmercury (MeHg) and their nonexposed controls were administered an adaptation of a standardized test of visual recognition memory. Exposed animals showed recognition deficits in that they directed significantly less visual attention to novel stimuli than did controls. These results ...
Allen M C - - 1986
The early auditory and visual abilities of 47 extremely premature infants (31 born less than or equal to 28 weeks gestation) were assessed with a bell, a light and an optokinetic nystagmus drum. All the infants altered to the bell and blinked to the light from 25 weeks postconceptional age ...
Stager D R - - 1986
One hundred esotropic infants were assessed by preferential-looking (PL) for monocular acuity and stereopsis before the initiation of treatment. PL acuity of infantile esotropes who freely alternated fixation and of preferred eyes of unilateral esotropes was not significantly different from monocular acuity of age-matched normal infants. PL acuity of non-preferred ...
Harris S J - - 1986
For amblyopic subjects, square-wave gratings, such as those used in preferential looking tests of infants' vision, yield more optimistic estimates of visual acuity than complex stimuli such as letters. A complex stimulus--a schematic face pattern--has recently been shown (Harris et al, IOVS 25:782, 1984) to permit preferential looking estimates of ...
Stebbins A L - - 1986
Infant visual acuities have been a difficult measurement to obtain for a number of reasons. This study evaluates the clinical usefulness of the Infant Vision Tester, a new preferential-looking instrument. Twenty-eight infants from age 2 months to 22 months were followed on a bi-monthly basis and their visual acuities were ...
Streletz L J - - 1986
Brainstem auditory evoked potentials (BAEP) were studied in 93 newborns (49 preterm and 44 fullterm) admitted to the neonatal intensive care unit. One group of 42 infants (28-42 wk CA) were considered at low risk for perinatal complications and served to establish the normal ranges of the BAEP parameters (wave ...
Wright K W - - 1986
Accurate assessment of visual function in infants and preverbal children is difficult because of the dependence on vision tests that require the patient's cooperation. In an attempt to resolve this problem, we evaluated pattern visual evoked potentials (PVEPs) obtained on infants under chloral hydrate sedation. Ten patients were studied--four with ...
Kohl P - - 1986
A clinical pilot study comparing refractive error and preferential looking (PL) visual acuity in infants 2 to 12 months of age is described. The PL visual acuity of 30 normal infants without significant visual disorders was assessed using the Acuity Card Procedure. Near retinoscopy was used to determine refractive error. ...
Ferrari F - - 1986
Visual orientation to the human face was studied by the method of Brazelton in 15 fullterm newborns on the 4th-5th day of life and in 21 premature newborns (gestational age 27-37 weeks) tested weekly up to 40 weeks conceptional age. No evidence of visual orientation was found before 33 weeks. ...
Klein A J - - 1986
The effects of high- and low-pass masking on waves I and V of the auditory brain stem response (ABR) were measured in normal infants who were 2-4 weeks old, and in adults. The signal was a 4-kHz tone pip presented at 86 dB peak equivalent sound-pressure level (p.e.SPL). The masking ...
Woolf N K - - 1986
The development of the positive endocochlear potential (EP), the negative anoxic EP, and the organ of Corti potential were measured at various postnatal ages in the Mongolian gerbil, beginning at 8 days after birth (DAB). The organ of Corti potential (OCP) was present at 8 DAB but averaged 21% less ...
McDonald M - - 1986
An "acuity card" technique has been developed for rapid assessment of visual acuity in infants. In this procedure an adult observer shows the infant a series of cards that contain gratings of various spatial frequencies and estimates acuity as the highest spatial frequency that the infant is judged to see. ...
Streri A - - 1986
Tactual discriminative abilities out of the control of vision are studied in 5-month-old infants, and compared with their visual discriminative abilities. The relevance of a habituation/reaction to novelty procedure in the tactual modality is tested. An infant control procedure is used in both modalities on 2 independent samples of 32 ...
van Hof-van Duin J - - 1986
The development of visual acuity during the first year of life was assessed in 91 normal fullterm infants and 36 preterm infants with minimal perinatal complications, using the forced-choice preferential looking technique. Acuity in the preterm infants lagged behind that of the fullterm infants up to the age of 6-8 ...
Yuodelis C - - 1986
The anatomical development of the human fovea has been sampled from 22 weeks gestation to adulthood, using both qualitative and quantitative methods. The foveal depression continues to deepen after birth until 15 months, due to the migration of the cells of the inner retina toward the periphery. Before birth the ...
Chin K C - - 1985
We used a signal averager with light emitting diode goggles as the photostimulator to study the development of the visual evoked potentials in 40 normal neonates of between 23 and 42 weeks' gestation. All except two infants of less than 24 weeks' gestation had replicable visual evoked potentials. A negative ...
Gwiazda J - - 1985
Acuity for vertical, horizontal, and oblique gratings was measured in 77 infant astigmats using a preferential looking procedure. Measurements were made with the refractive error uncorrected. Most of the infant astigmats were slightly to moderately hyperopic with respect to the test distance of 50 cm. Their acuity was not significantly ...
Sinnott J M - - 1985
Frequency and intensity DLs were measured in 26 human infants (ages 7-9 months) and six young adults using a repeating standard "yes-no" operant headturning technique and an adaptive staircase (tracking) psychophysical procedure. Subjects were visually reinforced for responding to frequency increments, frequency decrements, intensity increments, or intensity decrements in an ...
Dryden R M - - 1985
Probing of the lacrimal outflow system is commonly performed by ophthalmologists for treating nasolacrimal duct obstruction in infants or for intubating the lacrimal system. Visualization of the probe tip in the inferior meatus during probing insures the surgeon of reaching the nose with the probe. Similarly, visualization of the probe ...
Norcia A M - - 1985
The reliability of visual evoked potential (VEP) measurements of acuity was determined by estimating acuity for sinewave luminance gratings which were counterphase modulated at either 12 or 20 reversals/sec (rps). Gratings were swept in spatial frequency beyond the acuity limit and acuity was estimated from an extrapolation based on the ...
Dever G J - - 1985
There are no previously published studies on the prevalence of otitis media in Micronesia. As part of an Otitis Media Workshop to train health care workers from the Federated States of Micronesia in the identification and treatment of otitis media, 5-point prevalence studies were conducted to explore the prevalence of ...
Fulton A B - - 1985
The electroretinographic (ERG) responses of normal human infants have been studied in scotopic conditions. The relation of stimulus intensity to the amplitude of the b-wave of the ERG undergoes developmental changes during infancy. The maximum amplitude that can be obtained gradually increases to approach adult values by age 12 months. ...
Birch E E - - 1985
Monocular acuity and stereopsis were assessed by preferential-looking procedures in untreated infantile esotropes. Results were compared to an age-matched normal population. Monocular PL acuity was not significantly different from normal during months 3-14 for infantile esotropes who freely alternated fixation and for the preferred eyes of unilateral infantile esotropes. PL ...
Spungen L B - - 1985
Given the usefulness of visual behavior as an assessment method in older infants, a simple method of visual behavioral evaluation applicable in clinical settings was utilized to gather descriptive data on 42 infants at term. Using an "infant control" method for determining the duration of stimulus presentation, a series of ...
Quinn P C - - 1985
The familiarization/novelty preference paradigm was employed to study the effect of a delay (between the end of the familiarization phase and the beginning of the test phase) on discrimination of the orientation of square-wave gratings by 2- and 3-month-old human infants. Three stimulus pairs were studied: horizontal-vertical, non-mirror-image obliques, and ...
Fucci D - - 1985
The possible relationship between threshold and suprathreshold responses for the lingual tactile system was investigated. Lingual vibrotactile thresholds and suprathreshold magnitude function exponents were correlated for 26 adult subjects. A statistical analysis of the correlations indicated that there was no significant relationship between thresholds and exponents. Vibrotactile threshold and suprathreshold ...
Shea S L - - 1985
Preverbal infants and children with ocular misalignments do not perform well on standard clinical measures of binocular function which require accurate alignment of the eyes. In 1983, Birch and Held described a pupillary measure of binocular luminance summation that could be used to assess binocular function in strabismic infants. They ...
Folsom R C - - 1985
The effects of simultaneous pure-tone maskers on ABR wave V latency and amplitude were examined in three-month-old infants as a means of delineating the frequency specificity of these responses in the immature auditory system. Masking profiles at two intensities (60 and 40 dBn HL) were obtained for click, as well ...
Hainline L - - 1985
Developmental studies of infant eye movements may be a useful tool in the early diagnosis of visual abnormalities. We have measured saccades made by infants during the free scanning of stimuli differing in attentional value. When viewing stimuli with high attentional value, infants made saccades that had adult-like peak velocity/amplitude ...
McDonald M A - - 1985
Forced-choice preferential looking (FPL) and operant preferential looking (OPL) procedures for testing infant acuity typically require 15-45 min to derive an acuity estimate. This article presents a new acuity assessment technique ("acuity cards") that combines FPL/OPL stimuli with an observer's subjective assessment of an infant's looking behavior. The infant is ...
Anthony B J - - 1985
Probe stimuli which elicit activity reflexly provide a means of assessing 'top-down' effects of attentional manipulations while minimizing the perhaps insolvable problem of determining whether effects are due to post-perceptual selection or to changes in the input pathway. Parallel experiments on adults and infants presented acoustic and visual probes unpredictably ...
Chin K C - - 1985
Two preterm infants with peak serum bilirubin concentrations of 270 mumol/l and 200 mumol/l, respectively showed improvement in the wave peak latencies of the auditory and visual evoked potentials after exchange transfusion. The implications of this observation and the use of evoked potential recording in neonatal jaundice are discussed.
Placzek M - - 1985
Visual evoked responses (VERs) were elicited in 70 infants with postmenstrual ages between 30 and 39 weeks. On the basis of neurological and ultrasound examinations, 30 of the infants were classed as neurologically normal and 40 as abnormal: 26 of the latter had periventricular haemorrhage. Initially the VER consisted of ...
Bashinski H S - - 1985
Three experiments were conducted to investigate the dynamics of the human infant's (4 months old) visual fixation. The general finding that, over a series of trials, infants fixate longer to a complex than to a simple stimulus was replicated. The function relating fixation time to trials was shown to be ...
Beiser M - - 1985
Auditory brainstem evoked potentials (ABP) were recorded in 59 healthy neonates and infants whose age ranged from 3 days to 18 months (6 age groups). Latencies of individual waves and the interpeak latencies (IPL) of I-III, III-V and I-V were analysed. A different maturational pattern was observed in the pontomedullary ...
Walker-Andrews A S - - 1985
2 studies examined 5-month-old infants' sensitivity to auditory-visual specification of distance and direction of movement. In 1 experiment, infants were presented successively with 2 filmed events--1 of an automobile approaching, and the other of the same automobile driving away. A soundtrack that increased or decreased in amplitude was played along ...
Sokol S - - 1985
Studies of visual acuity in human infants between 1 and 6 months of age using the visual-evoked potential (VEP) and forced-choice preferential looking (FPL) have shown that acuity is one to two octaves higher by VEP estimates than by FPL estimates. In an attempt to study these differences, the authors ...
Birch E E - - 1985
The ability of infants to discriminate zero-disparity stimuli from both reverse contrast (rivalrous) and disparate (stereoscopic) stimuli was investigated in a two-alternative, forced-choice, preferential-looking paradigm. Few infants under 4 months of age demonstrated discrimination for any stimulus pairing. Of the infants tested at 4 months of age, approximately 70% preferred ...
Lobaugh N J - - 1985
The effect of hippocampal lesions was assessed in patterned (single) alternation (PA) and the partial reinforcement extinction effect (PREE), the two reward-schedule effects that appear earliest in ontogeny. Three groups of rat pups, with appropriate controls, were tested for each effect: lesion as infant/test as infant, lesion as infant/test as ...
Mayer D L - - 1985
Visual acuity for gratings was studied in 18 infants and children with generalized retinal degenerations using preferential looking (PL) procedures. Diagnoses were Leber's congenital amaurosis (12), Laurence-Moon-Bardet-Biedl-like syndromes (4) and metabolic disorders (2). ERG's were extinguished in 11 patients and much attenuated in seven patients. Acuities at all ages (two ...
Gwiazda J - - 1985
The orientation preferences of 70 infants aged 7 to 53 weeks with significant astigmatism [1.0 or more diopters (D)] were measured using a preferential looking procedure with paired gratings. The preference data show the consequences of the blurring effects of astigmatism when these are not compensatable by accommodation. Data from ...
Paludetto R - - 1985
This study was performed to determine whether covering the eyes with an opaque screen over the head end of the bassinet instead of the normal patch would improve the behavioral organization of jaundiced, but otherwise healthy, term infants treated with phototherapy. 38 matched infants were randomly assigned to have a ...
Fielder A R - - 1985
Fifty-three infants with delayed visual maturation (DVM) are presented. These have been classified according to their ocular and systemic features into three groups: DVM as an isolated anomaly, in association with mental retardation, and ocular abnormalities accompanied by DVM. The clinical features are discussed, particularly regarding the time and speed ...
Fernald R D - - 1985
We have measured the chromatic aberration and optical resolution of the lens of the African cichlid fish, Haplochromis burtoni as a function of growth. We found that in H. burtoni, lenses of all sizes have a longitudinal chromatic aberration of ca 1.9% of the focal length. The resolution of the ...
Mayer D L - - 1985
Preferential looking (PL) has been successful in the assessment of visual acuity of infants with eye disorders that place them at risk of amblyopia, such as non-alternating strabismus, anisometropia, and complete unilateral cataracts. However, PL acuities do not always conform to clinical expectations. In most esotropic infants, even untreated esotropes ...
Coryell J - - 1985
Eight children for whom measures of head preference and hand visualization had been determined in infancy were evaluated by parent questionnaire for hand preference at ages 3.5-6 yr. All six infants who maintained their heads to the right became right-handed as predicted, while neither infant with a non-right head orientation ...
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