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Teller D Y - - 1993
Tested monocularly, young infants classically show directional eye movement asymmetries, with optokinetic nystagmus (OKN) being more readily elicited by stimuli moving in the temporal-to-nasal (T-N) than in the nasal-to-temporal (N-T) direction. Since a counterphase grating is physically identical to two superimposed sinusoidal components moving in opposite directions, we wondered whether ...
Hansen R L - - 1993
Prenatal exposure to cocaine and amphetamines has been associated with many adverse effects in infants, including neurological abnormalities. Recent evidence shows that the visual system may be useful in infancy to evaluate neurological functioning. Visual evoked potentials (VEPs) and visual recognition memory testing were carried out on eight infants with ...
Berg K M - - 1993
Behavioral thresholds of 6-month-old infants and adults were determined for 1/3-octave filtered clicks and 300-msec noise bursts with center frequencies ranging from .5 to 8 kHz. For noise bursts, differences between infant and adult thresholds were largest at low frequencies and smallest at 8 kHz. For clicks, infants' thresholds were ...
Freeseman L J - - 1993
Cognitive performance and development is negatively correlated with fixation duration patterns during infancy, and evidence suggests that long-looking infants may process visual information more slowly than short-looking infants. 3 experiments described here tested the possibility that these differences may be due to differential sensitivity to global and local visual information. ...
Hartnett M E - - 1993
Despite surgical reattachment of the retina in infants with severe retinopathy of prematurity (ROP), visual acuity may decline. We performed gonioscopy and applanation tonometry on 26 eyes of 17 infants with severe ROP who were randomly selected and followed prospectively for 2 years. Of these 26 eyes, one eye of ...
Friendly D S - - 1993
Behavioral improvement in the quality of infant vision parallels neuroanatomic and neurophysiologic brain development. Progressive refinement of acuity can be tracked by means of tests that employ fixation and following, optokinetic nystagmus, preferential viewing, and pattern-evoked visual responses. These methods of evaluating vision in the preverbal child differ from each ...
Morrow J D - - 1993
The purpose of this article is to provide the pediatric nurse practitioner with an introduction to the literature on the use of visual-attention measures to screen for cognitive deficits in the infant. These measures rely on an infant's preference for novelty, that is, the tendency to look at a new ...
Carlson S E - - 1993
Docosahexaenoic acid (DHA; 22:6n-3) is important for normal visual development. We hypothesized that preterm infants fed formulas with marine oil as a source of DHA would have better visual acuity than infants fed formulas without marine oil, as measured by the Teller Acuity Card procedure. Marine oil (P < 0.001) ...
Catherwood D - - 1993
The robustness of infant haptic memory was assessed in terms of its capacity to withstand either a brief delay or potential retroactive "interference" from other haptic input. 48 infants (mean age 8 months) were familiarized haptically to a small cube or sphere with smooth or rough surface texture and subsequently ...
Flinn J M - - 1993
Auditory evoked potentials (AEPs) to click and name stimuli were recorded for 23 malnourished infants on admission to and 17 on discharge from hospital, together with those from age-matched controls. The number of peaks on the AEPs and the amplitude were examined. The malnourished infants' AEPs to click stimuli differed ...
Peterzell D H - - 1993
How many and what kinds of processes mediate infant visual attention? Are they influenced by stimulus "complexity?" Analyses were performed on visual fixation data from ninety 4-month-old infants; the time each infant spent looking at a black and white checkerboard pattern containing either 4 x 4, 12 x 12, or ...
Cohen Y E - - 1993
PURPOSE: The development of the umbo response in the gerbil was studied in order to further elucidate the contribution of the middle ear to the development of auditory function. MATERIALS AND METHODS: Laser interferometry was used to study the development of umbo velocity in Mongolian gerbils between 10 days after ...
Sudakoff G S - - 1993
Visualization of the posterior fossa during neonatal cranial sonography through the anterior fontanelle can at times be limited. To improve visualization of the posterior fossa, the foramen magnum was used as an acoustic window. Scans through the foramen magnum were obtained in addition to routine scans via the anterior fontanelle ...
Makrides M - - 1993
Recent studies have reported that formula-fed preterm infants score lower on visual and developmental tests relative to breast-fed preterm infants. This phenomenon has been associated with the presence of docosahexaenoic acid (DHA), an omega-3 fatty acid, in breast milk and its absence from infant formula. To investigate the possibility that ...
Horwood A M - - 1993
Seventy-five infants of state-registered orthoptists were observed by their mothers from birth to at least 6 months of age, with particular attention paid to the nature of any deviations noticed in the first few weeks. Most of the infants showed brief periods of inaccurate vergence during the first 2 months, ...
Zhang Z - - 1993
The development of components of VEP was studied in 150 infants and children between 2 weeks and 9 years of age participated as subjects. Ten adult subjects, 25 to 35 years of age were also studied. The results indicated that the VEP had a simple wave form, consisting of only ...
Parks T E - - 1993
A display in which a Kanizsa-like illusory-figure pattern of three notched circles was accompanied by several other notched circles was found to be relatively ineffective, thus confirming an important, but previously untested, suggestion. This ineffectiveness may have been due to a strengthened tendency of the visual system perceptually to 'explain' ...
Birch E - - 1993
The goal of the present study was to determine whether dietary supply of omega-3 essential fatty acid (EFA) influences visual development in healthy pre-term and full-term infants. Visual status was examined in human milk-fed infants (ample dietary omega-3 EFA supply) and corn oil-based formula-fed infants (no dietary omega-3 EFA; standard ...
Barnet A B - - 1993
This study evaluated the contribution of brainstem auditory evoked potentials (BAEPs) and median nerve somatosensory evoked potentials (SEPs) to the assessment of brainstem dysfunction in infants with myelomeningocele and Arnold-Chiari malformation. 16 infants under one year of age were studied. Six had infant brainstem syndrome (IBS). 11 had abnormally prolonged ...
Foxe J J - - 1993
Auditory brainstem responses (ABRs) were recorded to 500- and 2000-Hz bone-conducted (BC) tones from normal infants and adults. Infant ABR thresholds for the 500-Hz BC tones are significantly lower than their thresholds to 2000-Hz BC tones. Infant wave V latencies to 500-Hz BC tones are significantly shorter than those of ...
Primus M A - - 1992
This study investigated the hypothesis that estimates of infant auditory threshold are lowered by extending the duration of individual test trials such that infants have more time to detect and respond to the acoustic signal. Forty 8- and 12-month-old infants were evaluated with an operant procedure to determine response latencies ...
Fulton A B - - 1992
The determinants of infants' low scotopic visual sensitivity are controversial. Some interpret infants' scotopic vision as indicative of immature rod photoreceptor function while others attribute infantile sensitivities mainly to post receptoral immaturities. To date the rod photoreceptor sensitivity of human infants has not actually been measured. In the work reported ...
Pasman J W - - 1992
Recent studies on the maturation of auditory brainstem evoked responses (ABRs) present conflicting results, whereas only sparse reports exist with respect to the maturation of middle latency auditory evoked responses (MLRs) and auditory cortical evoked responses (ACRs). The present study reports the effect of preterm birth on the maturation of ...
Chen T C - - 1992
We examined 30 infants in whom cortical visual impairment was diagnosed during their first year of life to ascertain prognostic factors for the development of object vision, defined as the ability to recognize faces or hand-held toys. All patients were followed up for a minimum of 12 months. The most ...
Allen D - - 1992
Grating acuity was measured in 16-week-old human infants. Three measurement techniques were used: forced-choice preferential-looking (FPL), and two visual-evoked-potential (VEP) techniques. The stimuli were counterphase flickering sinewave gratings with a space-average luminance of -1.0 or 2.0 log cd/m2. Slightly different luminance-dependent changes occur between FPL and VEP acuities, suggesting that ...
Tsai C H - - 1992
Seventeen infants who had been treated with gentamicin on the first day of life as prophylaxis for prolonged rupture of membranes or maternal fever. Twenty-seven weight-matched healthy infants were used as controls. The auditory brainstem responses were evaluated on the third day and again on the tenth day of life. ...
Kohelet D - - 1992
Ten premature infants with low serum thyroxine levels (less than 84 nmol/L) were compared with 10 biochemically euthyroid infants to determine whether hypothyroxinemia in such infants can lead to alterations in the auditory pathway. The auditory pathway was studied between 6 and 11 wk of life by analyzing brainstem evoked ...
Birch E E - - 1992
The influence of dietary omega-3 fatty acid supply on visual acuity development was evaluated in very low birth weight (VLBW) infants using visual-evoked potential (VEP) and forced-choice preferential-looking (FPL) procedures at 36 and 57 wk postconception. The VLBW infants born at 27-33 wk postconception were randomized to one of three ...
Sokol S - - 1992
Previously, infants' grating acuity was found to be temporally tuned, but adults' grating acuity was not. In infants, acuity was higher for gratings phase alternating at 7.5 and 14 reversals/sec than for stationary gratings and gratings alternating at 2.5 or 23 reversals/sec. Also, when preferential looking (PL) and visually evoked ...
Trimarchi F - - 1992
The anatomy, neurophysiology, semiology, and pathology of the pupillary reflexes are reviewed. Recent advances in the demonstration of midbrain pathways projecting to and from the Edinger-Westphal (EW) nucleus are discussed. Observations of the pupillary diameter and reflexes in premature infants can be helpful in the diagnosis of neurological disorders. A ...
Van Campen L E - - 1992
There are few systematic comparisons of Etymotic ER-3A insert earphones versus supra-aural earphones in auditory brainstem response (ABR) measurement. We compared ER-3A insert earphones and two types of supra-aural earphones (TDH-39P and TDH-49P) in a group of normal hearing adults. Acoustic analyses revealed spectral and temporal differences among earphones. Behavioral ...
Zanker J - - 1992
Vernier acuity, i.e. the detection of a small misalignment between lines, is about one order of magnitude finer than the resolution of periodic gratings in adult humans. This hyperacuity is generally attributed to cortical mechanisms, and the time-course of its development seems to differ from the development of grating resolution ...
Molteno A C - - 1992
The Otago photoscreener is an optical instrument which gives a very sensitive indication of the accuracy with which a subject's eyes are fixing and focusing. Early experience suggested that this instrument could be used effectively to screen for the presence of amblyogenic factors in pre-verbal infants. This communication describes the ...
Vital-Durand F - - 1992
Since the early times of preferential looking (PL), improvement of procedures to test visual resolution in infants has reached the point where the technique is spreading to clinical practice as it is applicable to a large range of age with a high degree of reliability. Acuity cards allow estimation of ...
Ipata A E - - 1992
Binocular grating acuity of 65 neonates was measured using Teller acuity cards. At the time of testing, age corrected for prematurity ranged from -3 weeks to 2 weeks. On the basis of clinical data, serial ultrasound scans and EEG recording newborns were divided into 4 subgroups: fullterm low-risk (FLR, n ...
Hainline L - - 1992
Paraxial photorefraction was used to assess the development of accommodation and convergence in a large sample of infants under 1 year of age. The infants viewed small dolls placed at various distances (200-25 cm). The majority of infants at all ages demonstrated appropriate convergence for target distance, regardless of manifest ...
van Hof-van Duin J - - 1992
The effect of early visual experience on visual field size and grating acuity development was studied longitudinally in 36 appropriate for gestational age (AGA) and 26 small for gestational age (SGA) low-risk preterm infants. These were selected out of 194 very low birth weight (VLBW) infants (birthweight less than 1500 ...
Mikami A - - 1992
A preferential looking technique was used to measure detection of visual motion by 12 infant macaque monkeys (10 Macaca fuscata and 2 Macaca mulatta at ages between 1 and 100 days). A 0.25 cycles/deg square-wave grating was presented at speeds from 40 to 0.4 deg/s. The threshold was determined by ...
Goldie W D - - 1992
The brainstem auditory evoked potential (BAEP) is a neurophysiological study that provides functional information about the auditory system and brainstem. It provides information that is different from any other form of evaluation. This report tries to summarize technical and clinical information that will make the BAEP more meaningful for the ...
Hartmann E E - - 1992
Temporal contrast sensitivity was measured in 1.5- and 3-month-old infants using the FPL procedure. Stimuli were 0.1 c/deg counterphase-flickering sinewave gratings. Temporal rates ranged from 1 to 20 Hz. Because the spatial sinewave underwent phase shifts of 180 degrees, the target could not be seen unless the observer was able ...
Teller D Y - - 1992
The data on infant temporal contrast sensitivity functions (TCSFs) are scarce and contradictory. Earlier studies suggest that critical flicker frequency (CFF) is adultlike at 2-3 months postnatal (Regal, D. M., 1981 Vision Research, 21, 549-555), while contrast sensitivity at low temporal frequencies remains poor. If both of these findings are ...
Riese M L - - 1992
Visual and auditory orienting responses were compared in three cohorts of preterm infants (N = 351) born between 1977 and 1987. The infants were divided into one group born between 25 and 34 weeks gestational age (n = 140) and one group born between 35 and 37 weeks gestational age ...
Adams R J - - 1992
We used a new time-efficient procedure to obtain binocular contrast sensitivity functions (CSFs) from 80 infants aged 1-, 3-, 6-, and 12-months-old. The test consisted of 5 sets of large (50 by 28 cm) cards constructed by mounting a 7.2 degrees circular sine wave grating with 1 of 5 spatial ...
Went L N - - 1992
A dominant cone dystrophy spanning seven generations was found in a pedigree from the Netherlands. The onset of the decline of visual acuity started after the age of 20, while a near complete absence of blue cone function (a so-called tritan defect) already existed before the presence of any ophthalmological ...
McIsaac H - - 1992
Event-related brain potentials (ERPs) using auditory stimuli were recorded from 5- to 10-month-old infants and normal young adults with a passive tone sequence paradigm. A P3 (P300) component was obtained which demonstrated the same central-parietal maximum scalp distribution for both subject groups. P3 amplitude was smaller and its peak latency ...
Uauy R - - 1992
Dietary n-6 or n-3 fatty acid deficiencies result in changes in brain and retinal phospholipid composition that can affect cell membrane and organ function. An n-3 fatty acid deficiency has been associated with altered electroretinograms and reduced visual acuity in animals. Other promising methods for assessing the effects of fatty ...
Pryds O - - 1992
The effect of the stimulus rate on the single flash VEP amplitude and latency (N1) was studied in 26 mechanically ventilated, preterm infants during the first days of life. Significant decreases in VEP amplitude and increases in latency were observed within a series of 3 single flash VEPs recorded with ...
Adams R J - - 1992
The visual fixation of two groups of healthy newborn infants was tested at a mean age of three days. Mothers of the infants in one group received a single dose of meperidine (pethidine) during labour and delivery; those in the second group received no medication. Unlike infants of mothers who ...
Hansen R M - - 1992
Psychophysical area-intensity functions of individual 10-week-old human infants and adults were obtained in the dark adapted state, and in the presence of a steady background that elevated threshold 1 log unit above the dark adapted level. For dark adapted infants, the mean diameter for complete spatial summation (4.42 degrees; SD: ...
Kriss A - - 1992
The flash ERG and VEP have conspicuous immature features during the first 4 months following birth. The most marked maturational changes occur in ERG amplitude and VEP latency. Concurrent recording of the skin ERG and VEP provides information which is very useful in helping to arrive at a diagnosis in ...
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