Neurodevelopmental dimensional assessment of young children at high genomic risk of neuropsychiatric conditions.

Background: Individuals with 22q11.2 deletion are at considerably increased risk of neurodevelopmental and psychiatric conditions. There have been very few studies investigating how this risk manifests in early childhood and what factors may underlie developmental variability.

Minimal reporting guideline for research involving eye tracking (2023 edition).

A guideline is proposed that comprises the minimum items to be reported in research studies involving an eye tracker and human or non-human primate participant(s). This guideline was developed over a 3-year period using a consensus-based process via an open invitation to the international eye tracking community. This guideline will be reviewed at maximum intervals of 4 years.

Visual and Refractive Status of Children With Down's Syndrome and Nystagmus.

Purpose: Children with Down's syndrome (DS) are known to have poorer visual acuity than neurotypical children. One report has shown that children with DS and nystagmus also have poor acuity when compared to typical children with nystagmus. What has not been established is the extent of any acuity deficit due to nystagmus and whether nystagmus affects refractive error within a population with DS.

Neural modeling of antisaccade performance of healthy controls and early Huntington's disease patients.

Huntington's disease (HD), a genetically determined neurodegenerative disease, is positively correlated with eye movement abnormalities in decision making. The antisaccade conflict paradigm has been widely used to study response inhibition in eye movements, and reliable performance deficits in HD subjects have been observed, including a greater number and timing of direction errors. We recorded the error rates and response latencies of early HD patients and healthy age-matched controls performing the mirror antisaccade task.

Two-Dimensional Analysis of Horizontal and Vertical Pursuit in Infantile Nystagmus Reveals Quantitative Deficits in Accuracy and Precision.

Purpose: Infantile nystagmus (IN) presents with continuous, predominantly horizontal eye oscillations. It remains controversial whether those with IN have normal horizontal pursuit, while vertical pursuit has rarely been studied. We examined whether there are pursuit deficits associated with IN by investigating the effect of target direction, velocity, and amplitude.

Pupillary light reflex circuits in the macaque monkey: the preganglionic Edinger-Westphal nucleus.

The motor outflow for the pupillary light reflex originates in the preganglionic motoneuron subdivision of the Edinger-Westphal nucleus (EWpg), which also mediates lens accommodation. Despite their importance for vision, the morphology, ultrastructure and luminance-related inputs of these motoneurons have not been fully described in primates. In macaque monkeys, we labeled EWpg motoneurons from ciliary ganglion and orbital injections.

Quantitative Characterization of Smooth Pursuit Eye Movements in School-Age Children Using a Child-Friendly Setup.

Purpose: It could be argued that current studies investigating smooth pursuit development in children do not provide an optimal measure of smooth pursuit characteristics, given that a significant number have failed to adjust their setup and procedures to the child population. This study aimed to characterize smooth pursuit in children using child-friendly stimuli and procedures.

Methods: Eye movements were recorded in 169 children (4-11 years) and 10 adults, while a customized, animated stimulus was presented moving horizontally and vertically at 6°/s and 12°/s.

Two-Dimensional Analysis of Smooth Pursuit Eye Movements Reveals Quantitative Deficits in Precision and Accuracy.

Purpose: Small moving targets are followed by pursuit eye movements, with success ubiquitously defined by gain. Gain quantifies accuracy, rather than precision, and only for eye movements along the target trajectory. Analogous to previous studies of fixation, we analyzed pursuit performance in two dimensions as a function of target direction, velocity, and amplitude.

An automated segmentation approach to calibrating infantile nystagmus waveforms.

Infantile nystagmus (IN) describes a regular, repetitive movement of the eyes. A characteristic feature of each cycle of the IN eye movement waveform is a period in which the eyes are moving at minimal velocity. This so-called "foveation" period has long been considered the basis for the best vision in individuals with IN.

Infantile nystagmus: an optometrist's perspective.

Infantile nystagmus (IN), previously known as congenital nystagmus, is an involuntary to-and-fro movement of the eyes that persists throughout life. IN is one of three types of early-onset nystagmus that begin in infancy, alongside fusion maldevelopment nystagmus syndrome and spasmus nutans syndrome. Optometrists may also encounter patients with acquired nystagmus.

Saccades and fixations in children with delayed reading skills.

Purpose: Previous studies have reported that eye movements differ between good/average and poor readers. However, these studies have been limited to investigating eye movements during reading related tasks, and thus, the differences found could arise from deficits in higher cognitive processes involved in reading rather than oculomotor performance. The purpose of the study is to determine the extent to which eye movements in children with delayed reading skills are different to those obtained from children with good/average reading skills in non-reading related tasks.

Effect of Stimulus Type and Motion on Smooth Pursuit in Adults and Children.

Purpose: This study presents a two-degree customized animated stimulus developed to evaluate smooth pursuit in children and investigates the effect of its predetermined characteristics (stimulus type and size) in an adult population. Then, the animated stimulus is used to evaluate the impact of different pursuit motion paradigms in children.

Methods: To study the effect of animating a stimulus, eye movement recordings were obtained from 20 young adults while the customized animated stimulus and a standard dot stimulus were presented moving horizontally at a constant velocity.

The Effect of Gaze Angle on Visual Acuity in Infantile Nystagmus.

Purpose: Most individuals with infantile nystagmus (IN) have an idiosyncratic gaze angle at which their nystagmus intensity is minimized. Some adopt an abnormal head posture to use this "null zone," and it has therefore long been assumed that this provides people with nystagmus with improved visual acuity (VA). However, recent studies suggest that improving the nystagmus waveform could have little, if any, influence on VA; that is, VA is fundamentally limited in IN.

Neurochemical compartmentalization within the pigeon basal ganglia.

The goals of this study were to use multiple informative markers to define and characterize the neurochemically distinct compartments of the pigeon basal ganglia, especially striatum and accumbens. To this end, we used antibodies against 12 different neuropeptides, calcium-binding proteins or neurotransmitter-related enzymes that are enriched in the basal ganglia. Our results clarify boundaries between previously described basal ganglia subdivisions in birds, and reveal considerable novel heterogeneity within these previously described subdivisions.

The effect of unilateral disruption of the centrifugal visual system on normal eye development in chicks raised under constant light conditions.

The centrifugal visual system (CVS) comprises a visually driven isthmic feedback projection to the retina. While its function has remained elusive, we have previously shown that, under otherwise normal conditions, unilateral disconnection of centrifugal neurons in the chick affected eye development, inducing a reduced rate of axial elongation that resulted in a unilateral hyperopia in the eye contralateral to the lesion. Here, we further investigate the role of centrifugal neurons in ocular development in chicks reared in an abnormal visual environment, namely constant light.

The pupil's response to affective pictures: Role of image duration, habituation, and viewing mode.

The pupil has been shown to be sensitive to the emotional content of stimuli. We examined this phenomenon by comparing fearful and neutral images carefully matched in the domains of luminance, image contrast, image color, and complexity of content. The pupil was more dilated after viewing affective pictures, and this effect was (a) shown to be independent of the presentation time of the images (from 100-3,000 ms), (b) not diminished by repeated presentations of the images, and (c) not affected by actively naming the emotion of the stimuli in comparison to passive viewing.

First evidence of the feasibility of gaze-contingent attention training for school children with autism.

A number of authors have suggested that attention control may be a suitable target for cognitive training in children with autism spectrum disorder. This study provided the first evidence of the feasibility of such training using a battery of tasks intended to target visual attentional control in children with autism spectrum disorder within school-based settings. Twenty-seven children were recruited and randomly assigned to either training or an active control group.

Evidence for spatially-responsive neurons in the rostral thalamus.

Damage involving the anterior thalamic and adjacent rostral thalamic nuclei may result in a severe anterograde amnesia, similar to the amnesia resulting from damage to the hippocampal formation. Little is known, however, about the information represented in these nuclei. To redress this deficit, we recorded units in three rostral thalamic nuclei in freely-moving rats [the parataenial nucleus (PT), the anteromedial nucleus (AM) and nucleus reuniens NRe].

Calcium-binding protein immunoreactivity in Gudden's tegmental nuclei and the hippocampal formation: differential co-localization in neurons projecting to the mammillary bodies.

The principal projections to the mammillary bodies arise from just two sites, Gudden's tegmental nuclei (dorsal and ventral nuclei) and the hippocampal formation (subiculum and pre/postsubiculum). The present study sought to compare the neurochemical properties of these mammillary body inputs in the rat, with a focus on calcium-binding proteins. Neuronal calretinin (CR) immunoreactivity was sparse in Gudden's tegmental nuclei and showed no co-localization with neurons projecting to the mammillary bodies.

Visual Processing in Infantile Nystagmus Is Not Slow.

Purpose: Treatments for infantile nystagmus (IN) sometimes elicit subjective reports of improved visual function, yet quantifiable improvements in visual acuity, if any, are often negligible. One possibility is that these subjective "improvements" may relate to temporal, rather than spatial, visual function. This study aimed to ascertain the extent to which "time to see" might be increased in nystagmats, as compared to normally sighted controls.

Quick phases of infantile nystagmus show the saccadic inhibition effect.

Purpose: Infantile nystagmus (IN) is a pathological, involuntary oscillation of the eyes consisting of slow, drifting eye movements interspersed with rapid reorienting quick phases. The extent to which quick phases of IN are programmed similarly to saccadic eye movements remains unknown. We investigated whether IN quick phases exhibit 'saccadic inhibition,' a phenomenon typically related to normal targeting saccades, in which the initiation of the eye movement is systematically delayed by task-irrelevant visual distractors.

Enhancer evolution across 20 mammalian species.

The mammalian radiation has corresponded with rapid changes in noncoding regions of the genome, but we lack a comprehensive understanding of regulatory evolution in mammals. Here, we track the evolution of promoters and enhancers active in liver across 20 mammalian species from six diverse orders by profiling genomic enrichment of H3K27 acetylation and H3K4 trimethylation. We report that rapid evolution of enhancers is a universal feature of mammalian genomes.