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Background: The Frisby stereotest and the TNO test for stereoscopic vision are popular clinical tests for assessing stereoacuity: however, reference data for school-age children for the Frisby stereotest are limited. This study compared stereoacuity results of both tests in a large sample of typically developing school-age children. Methods: Primary (elementary school grades 1-6) and post-primary (high school grades 7-11) students aged 6-16 years were recruited and assessed in schools. Stereoacuity thresholds were measured using the Frisby and TNO stereotests. Children with ocular pathology, anisometropia of ≥1.00 D, interocular difference of visual acuity ≥0.2 logMAR, or strabismus were excluded. Results: A total of 212 children were recruited; data for 186 subjects were analyzed. Median Frisby stereoacuity scores were, for crossed disparity, 20 arcsec for primary and 10 arcsec for post-primary children and, for uncrossed disparity, 25 arcsec (primary) and 10 arcsec (post-primary). TNO stereoacuity was 60 arcsec for both age groups. For Frisby stereoacuity, scores of 85 arcsec (crossed) and 170 arcsec (uncrossed) or better were achieved by 95% of primary school children; scores of 85 arcsec (crossed and uncrossed) or better were achieved by 95% of post-primary subjects. A statistically significant difference in median stereoacuity scores was noted across age groups for the Frisby stereotest (crossed: z = 4.67, P < 0.0001; uncrossed: z = 4.67, P < 0.0001). No statistically significant difference in stereoacuity scores was noted with the TNO stereotest (z = 1.35, P = 0.18). A significant weak correlation was found between the Frisby and TNO stereotests (Frisby [crossed], r = 0.21 P < 0.005). Conclusions: These data describe normative values for the Frisby stereotest for children aged 6-16 years. Participants recorded significantly better stereoacuity scores with the Frisby stereotest than the TNO stereotest. The Frisby stereotest values are weakly correlated with the TNO stereoacuity test. [Copyright &y& Elsevier]

Three prereading children who named 0 to 3 of 20 targeted letters were taught to select the 20 printed letters when they heard spoken letter names. For all participants, letter-identification training resulted in naming for the majority of letters. [ABSTRACT FROM AUTHOR]

We conducted three experiments to reproduce and extend Perone and Courtney's (1992) study of pausing at the beginning of fixed-ratio schedules. In a multiple schedule with unequal amounts of food across two components, they found that pigeons paused longest in the component associated with the smaller amount of food (the lean component), but only when it was preceded by the rich component. In our studies, adults with mild intellectual disabilities responded on a touch-sensitive computer monitor to produce money. In Experiment 1, the multiple-schedule components differed in both response requirement and reinforcer magnitude (i.e., the rich component required fewer responses and produced more money than the lean component). Effects shown with pigeons were reproduced in all 7 participants. In Experiment 2, we removed the stimuli that signaled the two schedule components, and participants' extended pausing was eliminated. In Experiment 3, to assess sensitivity to reinforcer magnitude versus fixed-ratio size, we presented conditions with equal ratio sizes but disparate magnitudes and conditions with equal magnitudes but disparate ratio sizes. Sensitivity to these manipulations was idiosyncratic. The present experiments obtained schedule control in verbally competent human participants and, despite procedural differences, we reproduced findings with animal participants. We showed that pausing is jointly determined by past conditions of reinforcement and stimuli correlated with upcoming conditions. [ABSTRACT FROM AUTHOR]

Abstract: The spatial variation in central retinal function determined from mfERG was compared to co-localised measurements of cone density in two normal subjects. Individual cone cells in the parafoveal region of the retina were identified from 1°×1° images of the photoreceptor mosaic using a modified Heidelberg retina tomograph (HRT). The variation in cone density compared well with previous histology and retinal imaging studies and was strongly linearly correlated (r =0.98, p <0.001) with mfERG amplitude within the central retina. Retinal function determined from mfERG amplitude appears to directly reflect the density of the cone cells in this region. [Copyright &y& Elsevier]

Stereotypical behavior maintained by automatic reinforcement often does not result in harm but may be undesirable in some situations. In the current investigation, participants were 2 individuals who engaged in nonharmful stereotypical responses shown in an analogue functional analysis to be insensitive to social contingencies. After bringing these responses under stimulus control using differential punishment, both participants learned a mand to terminate punishment for stereotypy. We also assessed whether the mand could be brought under stimulus control. [ABSTRACT FROM AUTHOR]

Two men with intellectual disabilities initially demonstrated intermediate accuracy in two-choice matching-to-sample (MTS) procedures. A printed-letter identity MTS procedure was used with 1 participant, and a spoken-to-printed-word MTS procedure was used with the other participant. Errors decreased substantially under a delayed-sample procedure, in which the choice stimuli were presented first and the sample was presented only after 5 s without a response to the choice stimuli. [ABSTRACT FROM AUTHOR]

Abstract: We investigated relationships between retinal structure using optical coherence tomography (OCT) and retinal function using peripheral resolution acuity and multifocal electroretinograms (mfERG) in 56 subjects with a range of refractive errors (+0.50 to −15.00D). Retinal thinning occurred in moderate and high myopia which appeared to be primarily due to reduced thickness of the middle to inner retina (MIR) (outer plexiform layer to the nerve fiber layer). MIR thickness was correlated with reduced spatial resolution and delayed mfERG timing in the peripheral retina. The findings suggest the structure and function of the post-receptor retina is susceptible to disruption in moderately and highly myopic eyes. [Copyright &y& Elsevier]

This article assesses the state of the literature on word-attack skills and phonological awareness (PA) in individuals with mental retardation, in light of progress towards the development of effective teaching procedures. The literature contains promising findings. Studies have shown PA to be correlated with word-attack skills in individuals with mental retardation, as has been shown conclusively in typically developing children. This suggests that instruction in PA would facilitate the acquisition of word-attack skills in individuals with mental retardation, as it does with typically developing children. As of yet, however, very few experimental studies designed to demonstrate effective teaching procedures for PA and word-attack skills have been published. This research field might evolve most effectively and efficiently by following a two-step research program. First, test new teaching procedures in a series of small-N studies, each study incorporating modifications of teaching procedures based on the results of the previous study. Once procedures prove effective at this level, the resources necessary to pursue large-scale studies can be used to their best advantage. © 2007 Wiley-Liss, Inc. MRDD Research Reviews 2007;13:78–84. [ABSTRACT FROM AUTHOR]

Two experiments compared delayed matching-to-sample (DMTS) accuracy under 2 procedures in adults with mental retardation. In the trial-unique procedure, every trial in a session contained different stimuli. Thus, comparison stimuli that were correct on one trial were never incorrect on other trials in that session (or vice versa). In the 2-sample DMTS procedure, the same 2 comparison stimuli were presented on each trial, and their function changed quasi-randomly across trials conditional upon the sample stimulus. Across 2 experiments, 7 of 8 subjects showed the highest overall accuracy under the trial-unique procedure, and no subject showed consistently higher accuracy under the 2-sample procedure. Negative, exponential decay functions fit to logit p values showed that this difference was due largely to the steeper delay-mediated decline in sample control for the 2-sample procedure. Stimulus-control analyses indicated that, under the 2-sample procedure, the selection of the comparison stimulus on Trial N was often controlled by the comparison stimulus selection on Trial N-1 rather than the Trial-N sample stimulus. This source of competing stimulus control is not present in trial-unique procedures. Experiment 2 manipulated intertrial interval duration. There was a small but consistent increase in accuracy as a function of intertrial interval duration under the 2-sample procedure, but not under the trial-unique procedure. [ABSTRACT FROM AUTHOR]

Derived conditional discrimination was evaluated in 2 men with mental retardation whose language was limited to gestural requests. In each conditional-discrimination task, sample stimuli were arbitrary visual forms and comparison stimuli were black squares presented in 2 of the 4 corners of a computer screen. Subjects learned to select 1 position (P1) in the presence of 2 different samples (A1 and B1), and to select a different position (P2) in the presence of another 2 samples (A2 and B2). Next, new position responses (P3 and P4) were taught in the presence of A1 and A2, respectively. Tests then showed that the B1 and B2 sample stimuli controlled selection of P3 and P4, respectively. The data for 1 subject provided strong evidence for derived conditional responding, while the data for the other were suggestive. This is 1 of a very few studies of derived conditional discrimination in individuals without naming skills. [ABSTRACT FROM AUTHOR]

Investigates the ability of prereaders to match consonant-vowel-consonant (CVC) words. Difficulty of the visual discrimination tasks involving multi-element stimuli; Emphasis of prereaders on the first letter of a CVC word; Relationship between the children's single-letter and CVC word-matching.

Purpose: The Predicting Myopia Onset and progression (PreMO) risk indicator, developed using data generated from white children in the UK, incorporates age, spherical equivalent refraction (SER), axial length (AL) and parental myopia to stratify the likelihood of developing myopia. This study evaluated the PreMO's predictive accuracy using prospective datasets from independent samples of children in Hong Kong (HK) and an ethnically diverse cohort of children in the United Kingdom. Methods: Non‐myopic children (SER > –0.50 D) aged 6–8 and 9–10 years were scored using the PreMO risk indicator framework, integrating baseline cycloplegic SER, AL and parental myopia data. Scores were assigned risk categories as follows: 0 = no risk, 1–3 = low risk, 4–6 = moderate risk and 7–9 = high risk. SER at ≥15 years of age was used to define refractive outcomes as 'myopic' or 'not myopic'. PreMO's predictive accuracy was analysed via Receiver Operator Characteristic curves, with Youden's J‐Index identifying the optimal risk score threshold. Sensitivity, specificity and area under the curve were determined and compared with those of singular predictors, that is, SER < +0.75 D and AL ≥ 23.07 mm at 6–8 years. Results: In the cohort of children aged 6–8 years, a PreMO risk score ≥ 4 exhibited high sensitivity in predicting myopia onset in UK (0.97) and HK (0.94) children, with high specificity in UK (0.96) and moderate specificity in HK (0.64) children. In UK children aged 6–8 years, the PreMO outperformed singular predictors such as SER and AL. Among HK children aged 9–10 years, the PreMO score maintained high sensitivity (0.90) and moderate specificity (0.72). Conclusions: A PreMO risk score ≥ 4 is a strong predictive indicator for future myopia onset, particularly in UK children. Despite high sensitivity in both UK and HK cohorts, specificity varied, indicating the need for contextual application of the tool, particularly in pre‐myopic Asian children. [ABSTRACT FROM AUTHOR]

We compared performance on conditional and trial-unique delayed identity matching-to-sample procedures. In Experiment 1, participants with moderate to severe mental retardation were exposed to both procedures under a single, brief delay value. Three of 5 subjects showed higher accuracy in the trial-unique sessions. In Experiment 2, participants with mild mental retardation were exposed to delay values of 0, 2, 4, 8, and 16 seconds, randomized within each session. For 3 of 4 subjects, accuracy was highest with trial-unique, and lowest on the conditional matching-to-sample, at longer delays. Across the two studies, 6 of 9 subjects showed lower delayed matching accuracy when fewer rather than more stimuli were included in a session. [ABSTRACT FROM AUTHOR]

The classic literature suggests that individuals with MAs of less than 5 years may fail tasks that require same/different judgments. In Study 1 we used an assessment procedure that provided minimal instructional programming to determine whether 17 adults with MAs ranging from 2 years, 5 months to 4 years, 11 months would show accurate identity matching-to-sample. Stimuli were letter-like nonsense forms. Eight participants showed highly accurate matching. Eight of the 9 who failed were available for further study. Of these, 5 ultimately demonstrated highly accurate matching after training with standard fading procedures. These data suggest that a greater proportion of individuals with low MAs can exhibit generalized identity matching than previously documented in the literature. [ABSTRACT FROM AUTHOR]

An adult male with mild mental retardation, whose laboratory history included training in a match-to-sample task on 16 arbitrary relations among 16 visual stimuli and 2 auditory stimuli, had performances that showed the development of 112 additional arbitrary relations that had never been reinforced. In the present study, on 2-year and 3-year follow-up tests for these derived relations, his performances remained stable despite the absence of opportunities to practice these relations between the tests and the absence of explicit feedback during the tests. The similarity to the long-term stability of language was discussed. [ABSTRACT FROM AUTHOR]

This report describes development of spherical equivalent refraction (SER) and axial length (AL) in two population-based cohorts of white, European children. Predictive factors for myopic growth were explored. Participants were aged 6–7- (n = 390) and 12–13-years (n = 657) at baseline. SER and AL were assessed at baseline and 3, 6 and 9 years prospectively. Between 6 and 16 years: latent growth mixture modelling identified four SER classes (Persistent Emmetropes-PEMM, Persistent Moderate Hyperopes-PMHYP, Persistent High Hyperopes-PHHYP and Emerging Myopes-EMYO) as optimal to characterise refractive progression and two classes to characterise AL. Between 12 and 22-years: five SER classes (PHHYP, PMHYP, PEMM, Low Progressing Myopes-LPMYO and High Progressing Myopes-HPMYO) and four AL classes were identified. EMYO had significantly longer baseline AL (≥ 23.19 mm) (OR 2.5, CI 1.05–5.97) and at least one myopic parent (OR 6.28, CI 1.01–38.93). More myopic SER at 6–7 years (≤ + 0.19D) signalled risk for earlier myopia onset by 10-years in comparison to baseline SER of those who became myopic by 13 or 16 years (p ≤ 0.02). SER and AL progressed more slowly in myopes aged 12–22-years (− 0.16D, 0.15 mm) compared to 6–16-years (− 0.41D, 0.30 mm). These growth trajectories and risk criteria allow prediction of abnormal myopigenic growth and constitute an important resource for developing and testing anti-myopia interventions. [ABSTRACT FROM AUTHOR]

The role of the classroom assistant (CA) is considered pivotal in inclusive provision for pupils with additional needs. CAs' support of pupils who have a visual impairment (VI) is greatly underreported in the literature. Scaffolding theory was applied to investigate the role of CAs in supporting pupils who have a VI in mainstream schools in Northern Ireland, UK. Focus groups were conducted with 18 CAs who were embarking on an accredited VI-focused professional development programme. Findings revealed the majority of assistants had received no formal training to work with these pupils although they provided support in a wide range of ways to ensure their educational, social and physical inclusion in school. Although positive aspects of their contribution were described in inclusive terms, challenges were identified that mainly impacted on the participatory options of pupils with VI. Most prominently, minimal access to professional development engendered uncertainty that pupils were being appropriately and effectively supported. Viewed through the lens of scaffolding theory, CAs occupy a predominantly supporting role, with paucity in upskilling opportunities and hierarchical structures limiting further professional progression. More strategic consideration of the CA role could contribute to greater equity of access to education for children with VI. [ABSTRACT FROM AUTHOR]

This study demonstrates significant differences between the area of complete spatial summation (Ricco's area, RA) in eyes with and without non-pathological, axial myopia. Contrast thresholds were measured for six stimuli (0.01–2.07 deg2) presented at 10º eccentricity in 24 myopic subjects and 20 age-similar non-myopic controls, with RA estimated using iterative two-phase regression analysis. To explore the effects of axial length-induced variations in retinal image size (RIS) on the measurement of RA, refractive error was separately corrected with (i) trial lenses at the anterior focal point (near constant inter-participant RIS in mm), and (ii) contact lenses (RIS changed with axial length). For spectacle corrected measurements, RA was significantly larger in the myopic group, with a significant positive correlation also being observed between RA and measures of co-localised peripheral ocular length. With contact lens correction, there was no significant difference in RA between the groups and no relationship with peripheral ocular length. The results suggest RA changes with axial elongation in myopia to compensate for reduced retinal ganglion cell density. Furthermore, as these changes are only observed when axial length induced variations in RIS are accounted for, they may reflect a functional adaptation of the axially-myopic visual system to an enlarged RIS. [ABSTRACT FROM AUTHOR]

The article reports on a three year research study which investigated the visual and refractive profile of a population of children and adults with albinism in Northern Ireland. Researchers found that the estimated incidence rate of albinism in Northern Ireland is at least one in 4,500 and that the estimated prevalence rate of the disorder is at least one in 6,600.

Purpose. Previous studies have demonstrated an association between melatonin status and both refractive error and axial length in young adult myopes. This study aimed to determine if this relationship extends to a younger adolescent cohort. Methods. Healthy children aged 12–15 years provided morning saliva samples before attending Ulster University (55°N) for cycloplegic autorefraction and axial length measures. Participants completed questionnaires describing recent sleep habits and physical activity. Salivary melatonin was quantified using high-performance liquid chromatography-tandem mass spectrometry. Data collection for all participants occurred over a 1-week period (April 2021). Results. Seventy participants aged 14.3 (95% CI: 14.2—14.5) years were categorised by spherical equivalent refraction [SER] (range: −5.38DS to +1.88DS) into two groups; myopic SER ≤ −0.50DS (n = 22) or nonmyopic −0.50DS < SER ≤ +2.00DS (n = 48). Median morning salivary melatonin levels were 4.52 pg/ml (95% CI: 2.60–6.02) and 4.89 pg/ml (95% CI: 3.18–5.66) for myopic and nonmyopic subjects, respectively, and did not differ significantly between refractive groups (P = 0.91). Melatonin levels were not significantly correlated with SER, axial length, sleep, or activity scores (Spearman's rank, all P > 0.39). Higher levels of physical activity were associated with higher sleep quality (Spearman's rank, ρ = −0.28, P = 0.02). Conclusion. The present study found no significant relationship between morning salivary melatonin levels and refractive error or axial length in young adolescents. This contrasts with outcomes from a previous study of adults with comparable methodology, season of data collection, and geographical location. Prospective studies are needed to understand the discrepancies between adult and childhood findings and evaluate whether melatonin levels in childhood are indicative of an increased risk for future onset of myopia and/or faster axial growth trajectories and myopia progression in established myopes. Future work should opt for a comprehensive dim-light melatonin onset protocol to determine circadian phase. [ABSTRACT FROM AUTHOR]

Purpose: Controversy exists regarding the influence of peripheral visual experience on the onset and progression of childhood myopia. This longitudinal, observational study evaluated the relationship between relative peripheral refraction (RPR) and changes in refractive error and axial length (AL) over 12 months in White children aged 6–7 and 12–13 years with a range of baseline refractive errors. Methods: Cycloplegic baseline autorefraction at horizontal retinal eccentricities of 0° and ±30° were recorded with the Shin‐Nippon NVision‐K 5001 while AL was measured using the Zeiss IOLMaster 700. Measurements were repeated after 12 months on a subgroup. Refractive data were transposed into power vectors as mean spherical equivalent (M), J0 and J45. RPR was calculated by subtracting central from peripheral measurements. Participants were defined as myopic (M ≤ −0.50 D), premyopic (−0.50 D < M ≤ +0.75 D), emmetropic (+0.75 D < M < +2.00 D) or hyperopic (M ≥ +2.00 D). Results: Data were collected from 222 and 245 participants aged 6–7 and 12–13 years, respectively. Myopic eyes demonstrated, on average, more hyperopic RPR. Emmetropes and premyopes displayed emmetropic RPR, and hyperopes showed a myopic RPR. Fifty‐six 6‐ to 7‐year‐olds and seventy 12‐ to 13‐year‐olds contributed 12‐month repeated measures. Longitudinal data demonstrated a significant relationship between a more hyperopic RPR in the nasal retina and greater short‐term axial elongation in teens with myopia at baseline (β = 0.69; p = 0.04). Each dioptre of relative peripheral hyperopia in the nasal retina was associated with an additional 0.10 mm (95% CI: 0.02–0.18 mm) annual increase in AL. Conclusions: Hyperopic RPR in the nasal retina of myopic children is indicative of increased risk for rapid axial elongation and may be a useful metric to support decision‐making in myopia management. [ABSTRACT FROM AUTHOR]

Down syndrome (DS) is frequently associated with cataract, but there remains scant information about DS cataract morphology. Supra-nuclear cataracts in DS have been proposed as indicative of beta-amyloid (Aβ) aggregation and thus potential biomarkers for Alzheimer's (AD). This study employed anterior segment OCT (AS-OCT) and slit-lamp (SL) photography to image the crystalline lens in DS, compared with adult controls. Lens images were obtained post-dilation. Using MATLAB, AS-OCT images were analysed and lens opacities calculated as pixel intensity and area ratios. SL images were classified using LOCS III. Subjects were n = 28 DS (mean ± SD 24.1 ± 14.3years), and n = 36 controls (54.0 ± 3.4years). For the DS group, AS-OCT imaging revealed the frequent presence of small dot opacities (27 eyes, 50%) in the cortex and nucleus of the lens, covering an area ranging from 0.2–14%. There was no relation with age or visual acuity and these dot opacities (p > 0.5) and they were not present in any control lenses. However, their location and morphology does not coincide with previous reports linking these opacities with Aβ accumulation and AD. Four participants (14%) in the DS group had clinically significant age-related cataracts, but there was no evidence of early onset of age-related cataracts in DS. [ABSTRACT FROM AUTHOR]

Accessible summary: Children with learning disabilities often have problems with their eyesight.We tested the eyes of nine children and checked whether they needed glasses or bigger print.We found that when they got what they needed to see better, their behaviour improved.This is important because children with learning disabilities need to be able to see as well as anyone else. Background: Children with identified special educational needs are at higher risk than other children of having visual needs that are not adequately met. This paper evaluates the impact of addressing the visual needs of these children on behaviour and academic achievements in a number of case studies. Method: Nine children (4–11 years of age, from four classrooms), who attended a special school in a medium‐sized town in the UK, took part in the case studies reported here. The children were part of the Special Education Eyecare (SEE) Project. Six of the children were selected because they had unmet visual needs at baseline and required bespoke interventions to meet these needs; the other three children were selected because their visual needs had been met prior to the study and no further adjustments were needed. Repeated direct observations were conducted to assess the impact of the intervention on the children's behaviour in the classroom. The observer was "blind" with regard to the visual needs of the participants. Parents and teachers completed the Strength and Difficulties Questionnaire (SDQ) for each child, before and after the intervention. School files were analysed to assess effects on academic achievement. Findings: Subsequent to the implementation of bespoke visual adjustments, for example prescription of spectacles or changed seating in classroom, significant and sustained changes were observed with regard to the children's behaviour (i.e., increased engagement with peers and/or teachers and decreased off‐task behaviour). Strength and Difficulties Questionnaire scores showed improvements regarding total difficulties, emotional difficulties, hyperactivity and prosocial (kind and helpful) behaviour. Due to highly variable data in school files, the effects on academic achievement were inconclusive. Discussion: The case studies reported here explored changes in behaviour of children with identified special educational needs after their visual needs were met. Findings show a positive overall effect on the behaviour of these children. [ABSTRACT FROM AUTHOR]

Purpose Experimental animal models of myopia demonstrate that higher melatonin (Mel) and lower dopamine ( DA) concentrations actively promote axial elongation. This study explored the association between myopia and serum concentrations of DA and Mel in humans. Methods Morning serum concentrations of DA and Mel were measured by solid phase extraction -liquid chromatography -tandem mass spectrometry from 54 participants (age 19.1 ± 0.81 years) in September/October 2014 (phase 1) and March/April 2016 (phase 2). Axial length ( AL), corneal radii ( CR) and spherical equivalent refraction ( SER) were also recorded. Participants were defined as myopic if non-cycloplegic spherical equivalent refractive error ≤−0.50 DS at phase 1. Results Nine participants were lost to follow up. Mel concentrations were measurable for all myopes (phase 1 n = 25, phase 2 n = 22) and non-myopes (phase 1 n = 29, phase 2 n = 23). SER did not change significantly between phases ( p = 0.51). DA concentrations were measurable for fewer myopes (phase 1 n = 13, phase 2 n = 12) and non-myopes (phase 1 n = 23, phase 2 n = 16). Myopes exhibited significantly higher Mel concentrations than non-myopes at phase 1 (Median difference: 10 pg mL−1, p < 0.001) and at phase 2 (Median difference: 7.3 pg mL−1, p < 0.001) and lower DA concentrations at phase 2 (Median difference: 4.7 pg mL−1, p = 0.006). Mel concentrations were positively associated with more negative SER (all r ≥ −0.53, all p < 0.001), longer AL (all r ≥ 0.37, all p ≤ 0.008) and higher AL/ CR ratio (all r ≥ 0.51, all p < 0.001). Conclusion This study reports for the first time in humans that myopes exhibit higher serum Mel concentrations than non-myopes. This may indicate a role for light exposure and circadian rhythm in the human myopic growth mechanism. Further research should focus on younger cohorts exhibiting more dynamic myopic progression and explore the profile of these neurochemicals alongside evaluation of sleep patterns in myopic and non-myopic groups. [ABSTRACT FROM AUTHOR]

We taught three children with visual impairments to make tactile discriminations of the braille alphabet within a matching-to-sample format. That is, we presented participants with a braille character as a sample stimulus, and they selected the matching stimulus from a three-comparison array. In order to minimize participant errors, we initially arranged braille characters into training sets in which there was a maximum difference in the number of dots comprising the target and nontarget comparison stimuli. As participants mastered these discriminations, we increased the similarity between target and nontarget comparisons (i.e., an approximation of stimulus fading). All three participants' accuracy systematically increased following the introduction of this identity-matching procedure. [ABSTRACT FROM AUTHOR]

Background/Objectives : The measurement of axial length (AL) is important to monitor the success of interventions to slow childhood myopia, but traditional biometers are expensive for clinicians to acquire. To address this, Oculus has developed the Myopia Master (MM), which measures auto-refraction (AR), corneal curvature (CC) and AL. This study compared inter-instrument and inter-examiner measures on the MM, IOL Master 700 (Carl Zeiss Meditec, Jena, Germany) and NVisionK-5001 (Shin-Nippon, Tokyo, Japan) in myopic children. Methods : Fifty-six myopic children participated (mean age 11.93 ± 1.93 years). A first examiner obtained the following under cycloplegia: (i) AR using the NVisionK, (ii) AL and CC using the IOL Master 700 and (iii) AR, AL and CC using the MM. The latter measures were repeated by a second examiner to assess inter-examiner agreement of the MM. Mean differences (MD) and 95% limits of agreement (LoA) were calculated. Spherical equivalent refraction (SER) was calculated using AR values. Acceptable LoA for AL, SER and CC were defined as ±0.05 mm, ±0.40 D and ±0.06 mm, respectively. Results : Inter-instrument LoA between the MM and IOL Master 700 for AL and CC were acceptable (MD 0.02 mm; 95%LoA -0.02 to 0.06 mm and MD 0.025 mm, 95% LoA -0.03 to 0.08 mm, respectively). SER measures between the NVisionK-5001 and MM were not acceptable (MD -0.44 D, 95% LoA -0.91 to 0.03 D). SER values were, on average, 0.44 D more negative when using the MM. Inter-examiner measures on the MM were all acceptable (AL MD 0.00 mm; 95% LoA -0.04 to 0.04 mm; SER MD -0.01 D; 95% LoA -0.33 to 0.32 D; CC MD 0.01 mm; 95% LoA -0.03 to 0.05 mm). Conclusions : The MM demonstrated excellent inter-examiner repeatability. Inter-instrument agreement between the MM and IOL Master 700 for the AL and CC measures showed excellent agreement. The MM over-estimated myopia SER compared with the NVisionK-5001.

Introduction: This work aimed to establish the largest UK and Ireland consensus on myopia management in children and young people (CYP)., Methods: A modified Delphi consensus was conducted with a panel of 34 optometrists and ophthalmologists with expertise in myopia management., Results: Two rounds of voting took place and 131 statements were agreed, including that interventions should be discussed with parents/carers of all CYP who develop myopia before the age of 13 years, a recommendation for interventions to be publicly funded for those at risk of fast progression and high myopia, that intervention selection should take into account the CYP's hobbies and lifestyle and that additional training for eye care professionals should be available from non-commercial sources. Topics for which published evidence is limited or lacking were areas of weaker or no consensus. Modern myopia management contact and spectacles are suitable first-line treatments. The role and provision of low-concentration atropine needs to be reviewed once marketing authorisations and funding decisions are in place. There is some evidence that a combination of low-concentration atropine with an optical intervention can have an additive effect; further research is needed. Once an intervention is started, best practice is to monitor non-cycloplegic axial length 6 monthly., Conclusion: Research is needed to identify those at risk of progression, the long-term effectiveness of individual and combined interventions, and when to discontinue treatment when myopia has stabilised. As further evidence continues to emerge, this consensus work will be repeated to ensure it remains relevant., (© 2024 The Author(s). Ophthalmic and Physiological Optics published by John Wiley & Sons Ltd on behalf of College of Optometrists.)

Myopia is becoming increasingly common in young generations all over the world, and it is predicted to become the most common cause of blindness and visual impairment in later life in the near future. Because myopia can cause serious complications and vision loss, it is critical to create and prescribe effective myopia treatment solutions that can help prevent or delay the onset and progression of myopia. The scientific understanding of myopia's causes, genetic background, environmental conditions, and various management techniques, including therapies to prevent or postpone its development and slow its progression, is rapidly expanding. However, some significant information gaps exist on this subject, making it difficult to develop an effective intervention plan. As with the creation of this present algorithm, a compromise is to work on best practices and reach consensus among a wide number of specialists. The quick rise in information regarding myopia management may be difficult for the busy eye care provider, but it necessitates a continuing need to evaluate new research and implement it into daily practice. To assist eye care providers in developing these strategies, an algorithm has been proposed that covers all aspects of myopia mitigation and management. The algorithm aims to provide practical assistance in choosing and developing an effective myopia management strategy tailored to the individual child. It incorporates the latest research findings and covers a wide range of modalities, from primary, secondary, and tertiary myopia prevention to interventions that reduce the progression of myopia., Competing Interests: Declaration of conflicting interestsThe author(s) declared the following potential conflicts of interest with respect to the research, authorship, and/or publication of this article: JBJ discloses European patent EP 3 271 392, JP 2021-119187, and US 2021 0340237 A1: „Agents for use in the therapeutic or prophylactic treatment of myopia or hyperopia”; AG discloses grants from Alcon, Bausch&Lomb, Zeiss, Teleon, J&J, CooperVision, Hoya, Essilor, Thea, Polpharma, Viatris, consultation: Polpharma, Eyerising, lectures: Thea, Polpharma, Viatris, member of Advisory Boards: Nevakar, GoCheckKids and Thea; JAG discloses editorial board memberships: IOVS, TVST, OPO, grants panel: Fight for Sight UK, consultant for several companies, however the consultancy fee is paid directly by the company to an eye research charity chosen by the company; RCB discloses editorial board memberships: Investigative Ophthalmology and Visual Science (IOVS), Current Eye Research, Scandinavian Journal of Optometry and Visual Science (SJOVS). JRP discloses consultant: Essilor, Hoya, Sightglass, Vyluma, Government funding by ZonMw; JSW discloses consultant: Alcon, Allergan, AOS, Bausch & Lomb, CooperVision, CSIDryEye, DopaVision, M2C Pharmaceuticals, Medmont, Novartis, NuVision, Santen, Scope Ophthalmics, SightGlass, Théa, shares in AstonVision Sciences, Eyoto, Wolffsohn Research Limited, and funding by Alcon, Allergan, Johnson & Johnson Vision, Rayner, M2C Pharmaceuticals, Novartis, NuVision, Scope Ophthalmics, SightGlass, Théa, Topcon, The Eye Doctor; SW is employee of Carl Zeiss Vision International GmbH; SR discloses consultant: BHVI (C), Thea (C); DIF discloses trial support from CooperVision, Topcon and Vyluma Inc., consultant: Coopervision, Thea, Vyluma, EssilorLuxottica, Sightglass, Johnson and Johnson, and commercial interest in Ocumetra Ltd.KJS is in receipt of research funding from Hoya Vision and Vyluma Inc; SJM Is in receipt of research funding from Hoya Vision; HK is consultant for Hoya and Haag-Streit. The other authors declared no potential conflicts of interest with respect to the authorship, and/or publication of this article.

Background/objectives: Axial length, a key measurement in myopia management, is not accessible in many settings. We aimed to develop and assess machine learning models to estimate the axial length of young myopic eyes., Subjects/methods: Linear regression, symbolic regression, gradient boosting and multilayer perceptron models were developed using age, sex, cycloplegic spherical equivalent refraction (SER) and corneal curvature. Training data were from 8135 (28% myopic) children and adolescents from Ireland, Northern Ireland and China. Model performance was tested on an additional 300 myopic individuals using traditional metrics alongside the estimated axial length vs age relationship. Linear regression and receiver operator characteristics (ROC) curves were used for statistical analysis. The contribution of the effective crystalline lens power to error in axial length estimation was calculated to define the latter's physiological limits., Results: Axial length estimation models were applicable across all testing regions (p ≥ 0.96 for training by testing region interaction). The linear regression model performed best based on agreement metrics (mean absolute error [MAE] = 0.31 mm, coefficient of repeatability = 0.79 mm) and a smooth, monotonic estimated axial length vs age relationship. This model was better at identifying high-risk eyes (axial length >98th centile) than SER alone (area under the curve 0.89 vs 0.79, respectively). Without knowing lens power, the calculated limits of axial length estimation were 0.30 mm for MAE and 0.75 mm for coefficient of repeatability., Conclusions: In myopic eyes, we demonstrated superior axial length estimation with a linear regression model utilising age, sex and refractive metrics and showed its clinical utility as a risk stratification tool., (© 2024. The Author(s), under exclusive licence to The Royal College of Ophthalmologists.)

Cerebral Visual Impairment (CVI) is a common condition in the UK. Patients with conditions associated with CVI are frequently seen in paediatric ophthalmology clinics offering eye care professionals an opportunity to identify children proactively. In most cases CVI occurs as part of a neurodevelopmental condition or as a feature of multiple and complex disabilities. However, CVI can also be seen in children with apparently typical development. In some cases, high contrast visual acuity is normal and in other cases severely impaired. As such, identification of CVI requires evaluation of aspects of visual performance beyond high contrast acuity and consideration that visual function of those with CVI may fluctuate. Few paediatric ophthalmologists have received formal training in CVI. The detection and diagnosis of CVI varies across the UK and patients report hugely different experiences. A diagnosis of CVI is made based on professional clinical judgement and it is recognised that individual perspectives and local practice in the specific methodologies of assessment will vary. A systematic review and survey of professionals is underway to attempt to reach agreement on diagnostic criteria. Nonetheless, established pathways and published protocols can offer guidance on how a paediatric ophthalmology service can approach assessment of the child with suspected CVI. The purpose of this paper is to present a summary of research and clinical practice methods for detecting and diagnosing CVI in a paediatric ophthalmology outpatient setting. It represents current understanding of the topic and acknowledges the evolving nature of both practice and the evidence-base. A rapid literature review was undertaken to identify articles relating to clinical investigation of children with CVI. A focus group of QTVI and subject matter experts from sight loss charities was undertaken to address areas which were not covered by the literature review., (© 2022. The Author(s).)

Significance: Pupillometry protocols evaluating rod/cone- and melanopsin-driven responses often use mydriatics to ensure maximal stimulus exposure; however, retinal effects of mydriatics are not fully understood. We demonstrate that dilation with either atropine or phenylephrine results in similar enhancements of rod/cone- and melanopsin-driven pupil responses., Purpose: The purposes of this study were to compare the effects of atropine, a muscarinic antagonist, and phenylephrine, an adrenergic agonist, on consensual pupil responses and to assess the repeatability of pupil metrics without mydriasis., Methods: Right eye pupil responses of 20 adults aged 21 to 42 years were recorded before and 45 minutes after instillation of 0.5% atropine or 2.5% phenylephrine in the left eye. Stimuli were presented to the left eye and included six alternating 1-second 651-nm "red" and 456-nm "blue" flashes. Metrics included baseline pupil diameter, maximal constriction, 6- and 30-second post-illumination pupil responses, and early (0 to 10 seconds) and late (10 to 30 seconds) areas under the curve., Results: Dilation of the stimulated eye with either mydriatic significantly increased the 6-second post-illumination pupil response and early and late areas under the curve for blue stimuli, and early area under the curve for red stimuli (P < .05 for all). Melanopsin-driven post-illumination pupil responses, achieved with either phenylephrine or atropine, did not significantly differ from each other (P > .05 for all). Without mydriasis, intersession intraclass correlation coefficients for pupil metrics were 0.63 and 0.50 (6- and 30-second post-illumination pupil responses, respectively) and 0.78 and 0.44 (early and late areas under the curve, respectively) for blue stimuli, with no significant difference between sessions (P > .05 for all)., Conclusions: Dilation with phenylephrine or atropine resulted in similar enhancements of the rod/cone- and melanopsin-driven pupil responses, despite differing mechanisms. Early pupil metrics without mydriasis demonstrated moderate to good intersession repeatability.

Significance: This study highlights potential differences that can arise in gaze-position estimates from first Purkinje image-based eye trackers based on how individual Hirschberg ratios (HRs) are calculated., Purpose: The purpose of this study was to evaluate the accuracy and repeatability of eccentric-viewing, prism-based, and theoretical techniques that are routinely used to calibrate HR in first Purkinje image-based eye trackers., Methods: Hirschberg ratios of 28 participants (18 to 40 years old) were obtained using the PlusOptix PowerRef 3 photorefractor and eye tracker. In the gold standard eccentric-viewing technique, participants viewed eccentric targets (±12°, 4° steps) at 2 m. In the prism-based technique, 4 to 16Δ-D base-out and base-in prisms were placed in 4Δ-D steps before an eye occluded with an infrared filter; the fellow eye fixated a target at 1 m. Each participant's HR was calculated as the slope of the linear regression of the shift in Purkinje image relative to the pupil center for each target eccentricity or induced prism power. Theoretical HR was calculated from the participant's corneal curvature and anterior chamber depth measures. Data collection was repeated on another visit using all three techniques to assess repeatability. Data were also obtained from an Indian cohort (n = 30, 18 to 40 years old) using similar protocols., Results: Hirschberg ratio ranged from 10.61 to 14.63°/mm (median, 11.90°/mm) in the eccentric-viewing technique. The prism-based and theoretical techniques demonstrated inaccuracies of 12 and 4% relative to the eccentric-viewing technique. The 95% limits of agreement of intrasubject variability were ±2.00, ±0.40, and ±0.30°/mm for the prism-based, eccentric-viewing, and theoretical techniques, respectively (P > .05). Intraclass correlation coefficients (95% confidence interval) were 0.99 (0.98 to 1.00) for eccentric, 0.99 (0.99 to 1.00) for theoretical, and 0.88 (0.74 to 0.94) for prism-based techniques. Similar results were found for the Indian cohort., Conclusions: The prism-based and theoretical techniques both demonstrated relative inaccuracies in measures of HR compared with the eccentric-viewing technique. The prism-based technique exhibited the poorest repeatability.

Significance: Accommodative responses were significantly poorer in individuals with autism spectrum disorder (ASD) compared with age-matched typically developing control subjects, and hypoaccommodation was associated with reduced near visual acuity (NVA) and convergence., Purpose: Autism spectrum disorder is a neurodevelopmental disorder with a reported prevalence of 1.1 to 1.5%. Accommodative dysfunction has been noted in other developmental conditions including cerebral palsy and Down syndrome. The aim of this study was to investigate how accommodative accuracy and near visual function in ASD compared with typically developing control subjects., Methods: This study investigated accommodative function in children with ASD, in conjunction with other vision measures with habitual refractive corrections. Accommodative accuracy was assessed using modified Nott dynamic retinoscopy. Individual accommodative demand and response were calculated incorporating residual refractive error (difference between cycloplegic and habitual refractive state). Near visual measures included NVA, near point of convergence, fusional reserves, and stereoacuity. Cycloplegic autorefraction confirmed refractive error., Results: Accommodative responses were measured from 124 participants with ASD (6 to 17 years old) and 204 age-matched control subjects. There was no significant difference in the magnitude of residual refractive error between groups (P = .10). The prevalence of a clinically significant lag of accommodation was greater in the ASD group compared with control subjects (ASD = 17.4%, control subjects = 4.9%, χ = 13.04, P < .0001). Near visual acuity was significantly reduced in the ASD group with a clinically significant lag of accommodation (P < .01). A few participants (n = 24 control subjects, n = 14 ASD) had uncorrected or undercorrected refractive errors (spherical equivalent refractive error ≥+2.00 D, >1.00 DC), and when these were removed from analysis, there was still an increased prevalence of hypoaccommodation in ASD (14.7%)., Conclusions: Children with ASD were significantly more likely to have accommodative deficits (and associated near visual deficits) in their presenting refractive state than typically developing children. Appraisal of refractive error, accommodation, and NVA should be considered in visual assessment of children with ASD.

Persistent error patterns sometimes develop when teaching new discriminations. These patterns can be adventitiously reinforced, especially during long periods of chance-level responding (including baseline). Such behaviors can interfere with learning a new discrimination. They can also disrupt already learned discriminations, if they re-emerge during teaching procedures that generate errors. We present an example of this process. Our goal was to teach a boy with intellectual disabilities to touch one of two shapes on a computer screen (in technical terms, a simple simultaneous discrimination). We used a size-fading procedure. The correct stimulus was at full size, and the incorrect-stimulus size increased in increments of 10 %. Performance was nearly error free up to and including 60 % of full size. In a probe session with the incorrect stimulus at full size, however, accuracy plummeted. Also, a pattern of switching between choices, which apparently had been established in classroom instruction, re-emerged. The switching pattern interfered with already-learned discriminations. Despite having previously mastered a fading step with the incorrect stimulus up to 60 %, we were unable to maintain consistently high accuracy beyond 20 % of full size. We refined the teaching program such that fading was done in smaller steps (5 %), and decisions to "step back" to a smaller incorrect stimulus were made after every 5-instead of 20-trials. Errors were rare, switching behavior stopped, and he mastered the discrimination. This is a practical example of the importance of designing instruction that prevents adventitious reinforcement of maladaptive discriminated response patterns by reducing errors during acquisition., Competing Interests: This research was funded by grant no. P01HD055456 from the National Institute of Child Health and Human Development to the University of Kansas. Ethical Approval/Human Rights All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki Declaration and its later amendments or comparable ethical standards. This work was approved by the University of Kansas Institutional Review Board. Animal Welfare This article does not contain any studies with animals performed by any of the authors. Informed Consent Written informed consent and behavioral/verbal assent were obtained from all individual participants included in the study. Because the participant was not capable of giving written informed consent, the parents or legal guardian provided written consent, and the participant provided verbal and behavioral assent.

Anomalous visual processing has been described in individuals with autism spectrum disorder (ASD) but relatively few studies have profiled visual acuity (VA) in this population. The present study describes presenting VA in children with ASD (n = 113) compared to typically developing controls (n = 206) and best corrected visual acuity (BCVA) in a sub-group of children with ASD (n = 29). There was no statistically significant difference in presenting VA between groups (z = -1.75, p = 0.08); ASD group median VA (interquartile range, IQR) -0.05 logMAR (IQR: -0.125 to 0.025 logMAR) and typically developing control group -0.075 logMAR (IQR: -0.150 to -0.025 logMAR). Median BCVA was -0.175 logMAR (IQR: -0.200 to -0.125 logMAR) for the ASD sub-group. Clinicians should not anticipate reduced VA when assessing children with ASD.

Purpose: We explored risk factors for myopia in 12- to 13-year-old children in Northern Ireland (NI)., Methods: Stratified random sampling was performed to obtain representation of schools and children. Cycloplegia was achieved using cyclopentolate hydrochloride 1%. Distance autorefraction was measured using the Shin-Nippon SRW-5000 device. Height and weight were measured. Parents and children completed a questionnaire, including questions on parental history of myopia, sociodemographic factors, childhood levels of near vision, and physical activity to identify potential risk factors for myopia. Myopia was defined as spherical equivalent ≤-0.50 diopters (D) in either eye., Results: Data from 661 white children aged 12- to 13-years showed that regular physical activity was associated with a lower estimated prevalence of myopia compared to sedentary lifestyles (odds ratio [OR] = 0.46 adjusted for age, sex, deprivation score, family size, school type, urbanicity; 95% confidence interval [CI], 0.23-0.90; P for trend = 0.027). The odds of myopia were more than 2.5 times higher among children attending academically-selective schools (adjusted OR = 2.66; 95% CI, 1.48-4.78) compared to nonacademically-selective schools. There was no evidence of an effect of urban versus nonurban environment on the odds of myopia. Compared to children with no myopic parents, children with one or both parents being myopic were 2.91 times (95% CI, 1.54-5.52) and 7.79 times (95% CI, 2.93-20.67) more likely to have myopia, respectively., Conclusions: In NI children, parental history of myopia and type of schooling are important determinants of myopia. The association between myopia and an environmental factor, such as physical activity levels, may provide insight into preventive strategies., (Copyright 2015 The Association for Research in Vision and Ophthalmology, Inc.)

In addition to the discrimination of individual printed letters, beginning readers must learn to perceive individual letters within complex, whole-word stimuli. The present study shows that the discrimination of letters presented individually does not automatically entail the discrimination of 3-letter printed words that differ only in the first letter (e.g., sat, mat). Thirty-two children ranging in age from 3½ to 5½ years participated in two studies. All showed highly accurate discrimination of individual letters in identity matching-to-sample procedures before being exposed to the word-matching task. On the word-matching task, 21 of the 32 children showed accuracy of less than 85%, and 11 of these showed accuracy of 65% or less. Word-discrimination accuracy did not improve in retests of a subset of children after periods ranging from 3 weeks to 3 months. In Study 2, six children who initially showed relatively low word-matching accuracy were taught using fading procedures. Moreover, generalization to untaught words was shown. These results extend basic laboratory studies that have shown difficulties discriminating multi-element stimuli despite the discrimination of the individual component elements.