**Abstract**

This chapter adopts an integrative literature review to describe and analyze theories and empirical research on visual development, impairment, screening, and intervention. The purpose is to inform teachers on how to influence students' education and social growth through understanding vision. Vision is especially essential for reading, accessing classroom materials, and learning. Yet, in many countries, vision problems in children are not assessed and thus not treated. The negative consequences for individuals and society are often significant. Though there is an abundance of eye health specialists in developed countries, not all visual problems that influence learning and reading are screened or treated effectively. This is worse in developing countries where eye health infrastructure often is lacking. Even screening and treatment given through the eye healthcare system is not always sustainable, since regular follow-up is lacking. The literature review shows that vision is a developing sense important for learning and that teachers can screen children's vision and support visual development. It can be concluded that every child in the twenty-first century school should have teachers with knowledge in vision. An example of a higher education initiative is presented to illustrate possible further education for teachers in the area of vision.

**Keywords:** visual development, stimulation, learning through vision, vision screening, teacher education

## **1. Introduction**

The world is changing rapidly, and the necessity for good functional vision is greater than ever. Education is essential for the individuals' overall life quality and for personal, social, and occupational development. Societies depend on it for economic growth and democracy. Recent research revealed how important good vision is in all learning- and for all academic-related tasks. In classrooms around the world, visual inputs are involved up to 70% of the time [1], so even tiny disturbances can result in a lack of important information.

Unfortunately, not much has changed since Rogers, in 1924, claimed that the importance of vision in reading and writing is often overlooked [2, 3]. Even today few teachers have any special knowledge about the visual functions and vision disturbances [4] or how they affect learning, the development of motor skills and cognitive capacities. Reading is a particularly significant vision task depending on good visual acuity (VA) for detecting all the tiny details in a text. In addition,

it relies upon an intact functional visual attention span in the visual field (VF) for getting an overview of the next letters, the words to come, the end of line, and from where to continue reading the next text line. Vision is not a passive sensory system that is only receiving inputs; it is also an active and complex motor system that is continuously moving. The eyes must coordinate to fixate on the same spot, move around to different areas for searching, while the lenses adjust to the ever-changing locations. The goal is to give the brain clear inputs, no matter the distance. During reading, the gaze must jump precisely and should be coordinated from one fixation point to the next and adjust to the light level of the actual surrounding. This complexity indicates why vision must be considered in teaching [5–7]. There is no doubt that literacy is the foundation of almost all education and probably the most important skill to have in the twenty-first century, and this skill starts as a visual process. Thus, when children have problems with their vision, they may not be able to succeed in school [8].

Visual impairment is classified extensively by the International Classification of Diseases, ICD-11 [9]. Although the criteria are health classifications, many countries use them very strictly as eligibility criteria for educational services by the teacher for the visually impaired or blind. In most cases, only a significantly reduced VA and/or a VF loss after correction of refractive error will lead to services [10]. What is often not understood is that vision plays such an enormous role in learning, that even milder problems, which are frequent among children and youth must be considered in school. These problems will be the focus of this chapter. Several vision disturbances, not just decreased VA and VF, have a negative influence on the academic work, sports and leisure activities, and general learning. Such "milder" visual problems are often not addressed even in countries with a highly developed eye health-care system, although many children exhibit them [11]. If these problems are not identified, the children are left without treatment and sometimes even the wrong explanations are given for their learning problems. This may result in frustration, low school results, and a reduced self-esteem. Thus, regular vision screenings may be necessary in finding out whether children have the visual capacity to learn. Screenings are done by eye health professionals, but school-based vision screenings by trained teachers have shown to be effective [12–14].

In this chapter, we will describe and analyze the relationship between vision and learning, the implication of visual problems on reading, and how teachers can screen their students' vision more comprehensively and make interventions as necessary. It begins with (1) an introduction and the description of the methodology we adopted. This is followed up with (2) our inquiry about the relationship between vision and learning, (3) the impact of visual disturbances on reading, and (4) screening and intervention of visual functions through teachers. The chapter concludes with the description of a Continuing Professional Development (CPD) course based on the theoretical framework and results of this literature review.

#### **2. The integrative literature review methodology**

The theoretical framework of the literature review is based on teachers' understanding, identification, and intervention of children's vision and vision screening. Literature sources from various disciplines such as neuroophthalmology, ophthalmology, optometry, education, visual impairment, vision sciences, and vision rehabilitation were used. A thorough integrative literature review approach [15] was conducted to explore the relationship between vision and learning, the impact of

#### *Learning Is Visual: Why Teachers Need to Know about Vision DOI: http://dx.doi.org/10.5772/intechopen.93546*

impaired visual functions on learning, and the reasoning for visual screening and interventions conducted by teachers. In general, a literature review is well suited to review the theories and evidence that exist in a very specific area, such as the role of vision in learning. In addition, a literature review is helpful to provide an overview of the topic. This also seems important since there appears to be a knowledge gap about the relevance of intact visual functions in learning. A literature basis can also be a foundation for the development of a model for new theories and practices. It will be investigated in this chapter whether a new model of teachers' screening and intervention can be derived from the literature review. However, in order to be more specific, it was necessary to narrow down the very broad method of a "literature review." An integrative literature is described as.

*Most integrative literature reviews are intended to address mature topics or new, emerging topics. In the case of mature topics, the purpose of using an integrative review method is to overview the knowledge base, to critically review and potentially re-conceptualize, and to expand on the theoretical foundation of the specific topic as it develops ([15], p. 336).*

The new emerging topic that we would like to address is the greater emphasis that schools and teachers may possibly have in the area of prevention, screening, and intervention of vision problems. We altogether viewed 65 sources, from the years 1901–2020 using various databases and search engines, using keywords such as vision, visual development, visual stimulation, vision screening, and vision screening in schools. The sources were analyzed by the themes established in the introduction, namely, the relationship between vision and learning, the impact of vision problems on learning, and screening and intervention.
