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Significance\ud The development of visual acuity has often been looked upon as a function of age. This study considers whether cognition might also be a predictor of acuity in children. The results indicate that cognition is a predictor of acuity and therefore should play a role in vision evaluations and developmental research.\ud \ud Purpose\ud Prior studies have shown that changes in visual acuity in typically developing children occur beyond primary school age. However, these studies almost exclusively use chronological age as the sole predictor for visual development. Since many of the tasks used to measure acuity have a cognitive demand, it is possible that age is not the best predictor for changes in this function. The aim of this study was to explore the effect of cognition on the development of visual acuity, and to compare this predictor with age.\ud \ud Methods\ud The predictive ability of chronological age and cognition on acuity were assessed in a group of 81 typical children between five and eleven years old.\ud \ud Results\ud Analysis of resulting trajectories show that while age indeed was a good predictor, development of visual acuity was equally well predicted by cognition. Moreover, partial correlations showed a strong correlation between cognition and acuity when controlling for age but no significant correlation between age and acuity when controlling for cognition.\ud \ud Conclusions\ud These results suggest that age alone is not the optimal determinant for the development of visual acuity in typical school age children, as cognition was also found to be an important predictor.

This article provides an overview of research on social contagion in the context of education. We highlight the importance of students' social interactions in school, considering contagion between peers and contagion from teachers to students, using a motivation perspective. The framework of contagion is introduced broadly, followed by a focused review on social contagion in school environments, both peer and teacher related. Then we introduce methodology for mapping behavior change to networks that are a direct representation of school cohorts. We argue that these different lines of research can be coherently interpreted from a motivation perspective, suggesting the critical role of motivation in social contagion, in the context of education. We highlight the limited amount of research on positive contagion effects and we call for further investigation into ways in which to increase the contagion of positive, academic behaviors. Finally, the neuroscience behind social contagion, both for the mechanisms and the interactions, is discussed.

Background: Previous research indicates that a significant proportion of children underaccommodate\ud at 1/3 m. Accommodation may vary with task demand, so children may accommodate\ud appropriately if required, for example, when reading small print. This study explores the range\ud of accommodative responses elicited in typical children, under naturalistic conditions, to a range\ud of targets.\ud Method: We identified 24 typically developing children from the University of Reading Child\ud Database. Primary-school children attending UK Year 2 (age 6-7 years) or Year 6 (age 10-11\ud years) with minimum distance visual acuity of 0.200 logMAR and near visual acuity of 0.100\ud logMAR were recruited for participation. A remote haploscopic photorefractor was used to assess\ud naturalistic, sustained, binocular accommodative responses to a variety of targets. At 33 cm,\ud accommodative targets included individual letters, age-appropriate text in large print equivalent\ud to early primary-school books, small N5 equivalent print, a visual search task (“Where’s Wally?”), a\ud clown picture containing a range of spatial frequencies, and a children’s cartoon. Participants were\ud given minimal instructions for task completion. The target presentation order was counterbalanced.\ud The results reported in this study were obtained during a longer testing session involving\ud different target types and fixation distances.\ud Results: The accommodative response observed with each target varied across participants to\ud both the clown target and single letters of a size used in school reading books the accommodative\ud responses were 2.4±0.48 D (range 0.85-2.97 D) and 2.47±0.37 D (range 1.48-3.09 D), respectively.\ud The accommodative response to N5 print (3.06±0.52 D) was statistically better than all\ud other targets other than the visual search and larger print tasks (P

In this invited commentary, the authors discuss whether the use of minus lenses to aid control of intermittent exotropia has an alternative method of action. Conventional theory suggests that the lenses induce accommodation and therefore accommodative convergence to reduce the angle of deviation. We discuss evidence which suggests that convergence is induced to control the primary deviation and that the minus lenses allow this control by correcting refractive blur caused by additional vergence accommodation.

Purpose This study investigated whether vergence and accommodation development in pre-term infants is pre-programmed or is driven by experience.\ud Methods 32 healthy infants, born at mean 34 weeks gestation (range 31.2-36 weeks) were compared with 45 healthy full-term infants (mean 40.0 weeks) over a 6 month period, starting at 4-6 weeks post-natally. Simultaneous accommodation and convergence to a detailed target were measured using a Plusoptix PowerRefII infra-red photorefractor as a target moved between 0.33m and 2m. Stimulus/response gains and responses at 0.33m and 2m were compared by both corrected (gestational) age and chronological (post-natal) age. \ud Results When compared by their corrected age, pre-term and full-term infants showed few significant differences in vergence and accommodation responses after 6-7 weeks of age. However, when compared by chronological age, pre-term infants’ responses were more variable, with significantly reduced vergence gains, reduced vergence response at 0.33m, reduced accommodation gain, and increased accommodation at 2m, compared to full-term infants between 8-13 weeks after birth. \ud Conclusions When matched by corrected age, vergence and accommodation in pre-term infants show few differences from full-term infants’ responses. Maturation appears pre-programmed and is not advanced by visual experience. Longer periods of immature visual responses might leave pre-term infants more at risk of development of oculomotor deficits such as strabismus.