The impact of vision loss on the development of children from birth to 12 years: A literature review
Executive Summary
I. Introduction
The visual system's immediate and simultaneous processing of extended spatial information affords fundamental information of depth, object
permanence and constancies, brightness, and color. Loss of vision requires the successful integration of successive stimulus information from
intact sensory systems, primarily touch and hearing. Such loss impacts negatively on perceptual, motor, cognitive, as well as
social-interpersonal behavioral development.
This review summarizes major empirical findings relevant to developmental and educational issues for those Canadian children who are blind or
visually impaired and with no additional disabilities. The first part is devoted to infants and preschool-aged children up to six years of age.
The second part covers school ages from six to twelve years. Benchmarks in development for sighted children and associated issues for children
who are blind or visually impaired are discussed. The paper includes discussion of needs of these children and their families, outlines some
implications of the findings for parents, and includes suggestions for future research.
It must be noted at the outset that for a variety of reasons there is an unfortunate sparsity of formal scientific investigations specific to
children who are blind or visually impaired. Furthermore, owing to the inability of researchers to apply truly comparable and controlled
conditions of observation and experimentation, findings can be difficult to replicate. Hence one must proceed cautiously and interpret the
findings of specific reports in terms of the parameters within which they worked. To generalize too broadly in many instances would be both
inappropriate and counterproductive to developing a clear and well-founded understanding of the "world" of children who are visually
impaired or blind.
II. Studies of Developmental Norms
There have been several efforts in the past to determine developmental norms for children who are blind; however, applying findings from older
studies to the current population of children with visual impairments is often questionable. This is largely because of problems associated with
small sample sizes and a heterogeneous population, due to such factors as onset of blindness (i.e., acquired vs. present from birth), level of
vision, etiology of eye condition, and presence-or-absence of additional disabilities. Other mitigating factors include differences in
educational opportunities and family support. All of these can undermine attempts to establish developmental norms and it is not surprising that
there have been mixed findings with respect to identifying when developmental milestones are reached. Whereas some researchers have found a
general delay across all measures, others have reported only slight delays or findings within the normal range for certain milestones.
It has been argued that the frequency of disabilities additional to blindness is so high that a sample of children with no disabilities other
than congenital blindness might not represent the general population of children who are congenitally blind. For example in one study, the
frequency of language disorders among preschoolers who were blind or visually impaired was reported to exceed 80%. Hence, it is easy to see how
either unidentified disorders or non-representative samples might compromise generalizations to the overall population of children who are
blind.
Performance on spatial tasks has been related to the type of vision condition (i.e., etiology). Such findings show that unless individual
differences due to etiology are considered, strong conclusions regarding effects of visual impairment per se are compromised and can be
misleading. Although the importance of considering etiology as an independent factor has long been recognized, researchers have often failed to
dissociate etiology from vision level.
A recent major long-term study compared the motor, cognitive, personal-social, and communication development of children from 1 to 6 years of
age as a function of level of vision. Findings were lower developmental ages across all domains and slower rates of growth in motor and
personal-social domains for children whose vision ranged from nil to 20/800 compared to children whose vision was between 20/500 and 20/200.
Children with lower visual function were found to be much more likely to be diagnosed with cortical visual impairment, retinopathy of
prematurity and optic nerve hypoplasia than were children with higher visual function.
It has been argued that more would be learned if research focused on the variation within the population of children with visual impairments
rather than comparing this group with the sighted population. One example that underscores this point is the finding that a group of children
who were congenitally blind performed better on certain number-memory tests than those who were adventitiously blind, visually impaired, or
sighted. This study demonstrated the impact of congenital and adventitious blindness need to be differentiated, and that qualitative differences
between levels of vision are not fully understood.
III. Preschool Children
1. Sensory discrimination
An important question is whether or not vision impairment has an impact on the way other senses function, in particular, whether blindness could
result in improved auditory or tactile sensory discrimination (i.e., sensory compensation). Until recently it appeared that no consistent
pattern of findings supported either a notion of sensory compensation or its alternative. Other than general improvement as a function of age,
it had been generally concluded that auditory and tactile development of children who are blind are not influenced by vision loss.
However, researchers have recently found that some persons who were totally could localize sounds more accurately than could persons with
some residual vision. Accurate sound localization is an important skill for using hearing to explore the environment. The researchers suggested
that ability to utilize aural cues more efficiently than sighted persons might be explained by cortical reorganization. For example, it is
plausible that certain brain structures, which could be left otherwise "unused" because of a lack of visual input, might be recruited
to process auditory information.
Moreover, findings from recent neurological research suggest that there can be cortical reorganization when vision is impaired, and that this
reorganization might facilitate or enhance tactile discrimination capabilities. Further research is needed to investigate implications of
cortical reorganization and the conditions that facilitate compensation at a perceptual, experiential level.
2. Gross-motor development
Generally, either no delay or only slight delays have been reported in motor-skills of blind children that require stable, in-place movement
(such as sitting, rolling, and standing alone). However, more severe delays have been reported for those associated with locomotion (holding-up
head, crawling, creeping and walking). There can be a longer delay between crawling and walking for children who are blind relative to their
peers with vision. However, the published literature shows considerable lack of agreement in this area. For example, one long-term study found
that every gross-motor skill was acquired at a lower median age than was reported in a previous study.
A recent study found that the sequence of development differed between blind and sighted children. For example, the median age for
"rolls over intentionally from back to stomach" appeared to be younger than that indicated for non-handicapped children (5.0 vs. 6.4
months), but "rolls over intentionally from stomach to back" appeared to be older (6.0 vs. 4.0 months). Interestingly, the sequence of
these two milestones was reversed between the two groups. It should be noted that the infants in this particular study were receiving early
intervention, which might account for some of the findings.
Although most researchers report that locomotion is delayed for children who are blind, the reported ages for attaining these milestones
varies. For example, the median age for standing alone has been reported at both 13 and 25 months. Similarly, the median age for walking has
been reported to be just over 19 months in one study and from 25 to 36 months in another. Recent findings from one long-term study are median
ages of 10.0 and 15.0 months for "crawls forward" and "walking 10 feet alone without support" respectively. Interestingly,
the same study found that "walks up and down stairs alternating feet" was attained at a median age of 24.0 months compared to the
reported sighted norm of 30.0 months. Therefore, not all locomotion milestones are necessarily delayed for children who are blind.
Possible reasons for delayed locomotion for infants who are blind include overall motor slowdown, muscular readiness, the possibility that
vision is more important than other senses (e.g., sound) to motivation, and restricted opportunity. Parental attitude can either enhance or
restrict opportunity for motor development; it is possible that overprotection might contribute to delayed development. One researcher pointed
out that intervention such as experience in the prone position reduced or eliminated delays in locomotion, and concluded that the likely cause
of delayed locomotion was restricted opportunity. It has also been reported that although the prone position is important for muscle, posture,
and balance development, children who are blind seem to avoid this position. Therefore, it has been suggested to encourage the prone position as
a means of facilitating motor skills. This suggestion merits further examination.
The quality of movement is also affected by visual impairment. For example, children who are visually impaired often develop a wide and
awkward gait, outward-turned toes, and also tend to exhibit poor posture. It has been suggested that children who are blind need to be taught
about posture in order to develop walking ability and enhance quality of movement. There are several approaches used to teach posture and
gross-motor skills, but there is insufficient empirical data to clearly indicate which are best.
3. Reaching
Reaching, grasping, and throwing have been reported to be problem areas for children who are blind, and delays might be exhibited in midline
skills and transferring. However, although some researchers have reported apparent delays, others have found little or no delay in
reaching/grasping by children who are blind. Sighted children can usually see what they reach for, and standard milestones such as "reaches
persistently" and "unilateral reaching" can be credited for unsuccessful reaching for objects that are in view. Therefore,
researchers have a difficult problem deciding what tasks might be equated to draw comparisons between blind and sighted children's acquisition
of reaching.
Skills such as reaching, grasping, transferring, and throwing are typically associated with ball activities which are common for sighted
children, but are seldom part of life experiences of young children who are blind. Therefore, it has been argued that delays in associated
skills might be experiential, reflecting sensory or educational deprivation rather than motor deficit.
Children observed in long-term studies have typically received early intervention. Therefore, differences in findings might be partly due to
different kinds of intervention programs. Until there is more evidence dissociating differences in findings due to tasks, experience, and
intervention, strong conclusions cannot yet be made whether or not reaching behaviors are delayed.
One issue being investigated is the sequence of reaching and crawling for blind infants. Whether or not reaching is acquired before crawling,
delays in either can have an impact on purposeful use of the hands and related fine-motor development. Therefore, both reaching and crawling are
important milestones that need to be monitored, and blind infants can likely benefit from encouragement and promotion to facilitate both
activities.
4. Impact of blindness on fine-motor development
Some delays in fine-motor development have been reported and a greater range in the age of acquisition has been observed among children with
visual impairments than is usually observed among their sighted peers. Reasons for the delays and greater range of acquisition are not yet
clear. Fine-motor skill is crucial for accessing braille and for keyboard technology; therefore, the possibility of delays in fine-motor
development is a major concern. It is an unfortunate possibility that fine-motor issues might be overshadowed by issues associated with mobility
and orientation
5. Impact of blindness on cognitive development
It is generally agreed that vision is likely the most important modality for knowledge acquisition. Properties of objects such as color,
contour, size, and motion are essentially immediately accessible through vision. Other senses utilize successive sampling to acquire knowledge
about objects in the environment. Different senses also provide different kinds of information. For example, sound is fleeting and not typically
strongly associated with most defining properties of objects. Touch can be useful only for experiencing non-dangerous objects that are within
reach, and can be usually used for experiencing only part of an object at a time. Therefore, a child who is blind needs considerable guidance
and varieties of experiences in order to understand information that can be available to the sighted child with a glance. In particular, infants
and young children who are blind need considerable experience with objects and the external physical world in general in order to achieve
appreciable competence and confidence in dealing with their physical environment.
6. Object permanence
Object permanence is the concept that objects continue to exist even after they are removed from perception. Sighted children are typically
believed to demonstrate object permanence by searching for a toy that is first shown them, and then hidden from view (for example, under a
blanket). There are some reports that children who are blind are delayed relative to sighted children in reaching or searching for hidden
objects. However, there are a number of issues that require further research before conclusions can be drawn regarding influences of vision
impairment on object permanence or other areas of conceptual development.
It is important to note that tasks typically used to measure object permanence are mainly visual. Apparent deficits in object search could be
due to the impoverished information afforded when only sound cues are used. A related issue is the need to define behaviors relevant to
indicating object permanence. For example, whereas visual tracking and visual search is an active process, appropriate behavior when tracking by
sound alone is to remain perfectly still and quietly attentive. Therefore, sighted children and children who are blind might be expected to
exhibit markedly different behaviors to demonstrate an equivalent level of interest and awareness of objects.
Another important issue is the way in which children's understanding of their spatial environment might affect reach-and-search behavior.
That is, a child's understanding to reach for something is entwined with knowing where to reach. How a young child's understanding of spatial
layout might be influenced by auditory and tactile information in the absence of visual cues is an important issue underlying current
investigation.
7. Impact of blindness on language development
Reports have been mixed whether or not language milestones are delayed for children who are blind. Some researchers have reported that first
words could be delayed by 8 months to as much as 12 months relative to sighted peers. Others have reported findings within the range of sighted
norms.
One source of difficulty is that different researchers use different criteria. For example, one group of researchers interpreted "first
words" to mean "a 2-syllable repetition of the same sound ... not necessarily intended by the child as meaningful," which is
usually achieved around 8 months of age. However, some other researchers interpreted "first words" to mean "use of one clear
word," which is typically achieved at 10 to 11 months of age. The use of different criteria makes it difficult to compare findings in this
area.
Another potential source of problems is language disorder. The frequency of language disorders among preschoolers who are blind or visually
impaired has been reported to be over 80%, compared to less than 25% among sighted peers. Among with high incidence of disorder is an increased
likelihood for undiagnosed disorder and/or inadequately screened samples to confound language differences, caused by lack of vision, and
language disorders, which might have other causes. Language disorder is one contributor to the general issue of heterogeneity, which can be
problematic for an area of research in which sample sizes are often unavoidably small.
Despite these and other problems, researchers have provided evidence for language differences between blind and sighted children in the areas
of expressive language, comprehension, and parent child interaction. However, these differences were not simply in terms of ages in which
milestones are attained.
Expressive language
The first 50 words acquired by children who were blind were compared with those acquired by sighted children. The age and speed of acquisition
was parallel between the groups. In addition, the early words of both groups labeled things or events that acquired meaning in infancy. However,
there were differences in what qualities were salient for each group, and how the two groups of children used language. The children who were
blind labeled items that produced auditory, tactual or olfactory sensations (e.g., music, powder, basement) but sighted children's early words
included many names of objects that were primarily visually experienced (e.g., moon). Thus, both blind and sighted children's early words were
related to their perceptual experiences, but their experiences differed.
Children who are blind have been observed to use fewer modifiers (e.g., big, hot), fewer words used in social interaction (e.g., no, thank
you), and fewer function words (e.g., what, is) but more action words (e.g., up, go) than sighted children. It has also been observed that
children who are blind use words mainly to express their own actions or desires, whereas sighted children are likely to refer to actions
involving others. The last observation is not surprising, because children without vision are less likely to perceive actions that are not their
own.
Children's first words are mostly names of things. Names can be either specific (i.e., names of particular objects) or general (i.e., names
of classes of objects), depending how they are used. For example, "puppy" might be used to refer either to any dog or only to a
particular dog. Early vocabularies of children who are blind contain more specific names than do vocabularies of sighted children. One reason
might be that children who are blind don't have the opportunity to experience (and hence, label) more than one instance of most objects, but
sighted children experience seeing many different examples in real life and in pictures. In general, the vocabulary of children who are blind
includes more restricted meanings, narrower definitions, and different meanings than sighted children's vocabulary.
Children who are blind are reported to have difficulties using personal pronouns appropriately, and a one-year delay has been observed as the
median age for "uses first-person pronouns appropriately" (36 vs. 24 months), but considerable variation has also been observed. The
impact of language environment on language acquisition is not yet well understood.
Reports that children who are blind or severely visually impaired use words for which they have no sensory experience (verbalisms) have
provoked considerable discussion. Major issues here are whether or not such words were meaningless, and whether verbalism might be associated
with "loose thinking" or might be otherwise detrimental. These notions have not withstood critical review. Critical researchers have
argued that there was neither evidence that such words were meaningless, nor empirical support for the notion that there were undesirable
consequences if children who are blind use language that is visually based. Although verbalism is still discussed, the term appears less often
in the literature.
Comprehension
Research with respect to language comprehension of children who are blind is inconclusive. In one example, a median age of 24 months for
"follows two step directions" was observed relative to a sighted norm of 36 months, but the researchers involved in this study did not
suggest reasons for the apparently precocious performance. Another study examined verbal comprehension and expressive language of children
between 13 and 24 months of age who were blind or severely visually impaired. For some children, early expressive language developed in advance
of comprehension, but for others, it was delayed. Outcomes on later assessments were mixed.
Parent/child interaction
An important source of language differences between children who are blind and those who are not blind is their differing language environments.
A main component of a child's language environment is parent/child interaction. Two important factors for healthy parent/child interactions to
promote children's language development are the child's "readability," which facilitates parent involvement, and the parent's
responsiveness, which serves to acknowledge and extend the child's interests.
An early finding was that caregivers tended to talk considerably less to infants who were blind than they did to infants who were not blind.
One reason was that infants who were blind did not use the same non-verbal language as infants who were not blind. For example, it was observed
that blind infants didn't engage in eye contact, their smiles were neither automatic nor regular, and they didn't exhibit the same repertoire of
facial expressions as sighted infants. Thus, it was difficult for babies who were blind to initiate parent involvement.
It has been reported that mothers' voices don't necessarily evoke infant smiles, but that bouncing, tickling, and nuzzling almost always do.
This observation reinforces the value of physical contact between parents and blind infants. It was also noted that blind infants' hand behavior
indicated a range of wants, needs, and emotions. However, hand behavior can be more difficult to interpret than facial expressions. Thus,
mothers have been observed to misinterpret their infants' facial expressions as expressing disinterest, and to not recognize the ways that their
infants' hands showed clear interest and preferences.
There appears to be a general tendency for caregivers to supply early language to blind children instead of encouraging the children to
generate their own language. One example is how children name objects. Sighted children have many opportunities to see things and try to label
them, but children who are blind usually need to touch things to experience them. Rather than allowing their children to handle an object and
try to label it themselves, parents of blind children most commonly tend to supply labels.
In addition to being inclined to provide labels, parents whose children were blind frequently provided language that encouraged responses
(e.g., to answer a question, carry out a response, etc.) and provided fewer descriptive statements compared to parents of sighted children.
Sighted children often initiate topics, and exchanges frequently are about other persons or events in the environment. Compared with mothers of
sighted children, mothers of blind children have been observed to provide more topics, and most mother/child exchanges were focused on the child
rather than the environment. Suggestions for parents of children who are blind to facilitate expanding their children's language include
informing the children about what others are doing, expanding children's messages (e.g., Child says "blanket;" mother says
"Here's the blanket you asked for, isn't it soft?"), and including children who are blind in everyday routines.
8. Impact of blindness on social and emotional development
Neither infants who are blind nor their parents have the same access to the non-verbal communication that is common between parents and their
sighted infants. Therefore, it is possible for difficulties in mother/child interactions to put a child who is blind at risk emotionally. In
addition to possible difficulties in parent/child interaction, blindness can affect children's peer relations. Preschool peer-interactions are
mainly observed during play, and play is thought to enhance emotional health and most aspects of development. Therefore, several researchers
have studied play in order to investigate social and emotional development of children who are blind.
Social interaction
Several researchers have noted that whereas sighted children spend most of their playtime interacting with other children, children who are
blind spend about half their time in solitary play. Children who are blind are also more likely to choose to spend playtime with adults than
age-peers.
Blind children in nursery school were observed to have severe difficulty in social interactions with sighted peers. In particular, children
who were blind did not know the non-verbal rules including gestures and body movements that regulate inter-personal communication. They also had
problems taking part in dialogues, interpreting the meaning of other people's reactions, and expressing emotions. Although sighted children
initially showed interest and tried to engage the blind children in play, most later withdrew, because the children who were blind either showed
little interest or refused contact. Therefore, it is likely that early intervention is needed for preschool children who are blind to interact
effectively with sighted peers.
Researchers have observed older children who are blind to be very interested in interacting with other children who are blind, and have
argued that children who are blind need opportunities to interact with blind peers with whom they could identify and share experiences. In one
series of studies, all of the children observed who were blind had severe problems taking part in free-play. Reasons included that few of the
toys stimulated senses other than vision, sighted children used much non-verbal communication, and free-play situations were often noisy and
boisterous. Researchers suggested that children who were blind had difficulty following the meaning of the play, and therefore withdrew. In
contrast to free-play, children who were blind enjoyed structured activities such as listening to stories or playing games. Teachers took an
active part in structured activities by explaining rules and elaborating meaning. Participants remained in one place for the activity, children
took turns, and only one child would talk at a time. Thus, it was easier for children who were blind to follow the conversation and participate
in structured activities.
Shared teacher-child play intervention has been investigated as a means of enhancing play behavior of children who are blind. An adult can
provide a controlled environment with skill-specific support, modeling, and practice, and adults can help maintain play-themes while children
develop their skills.
Play behavior and symbolic play
In comparison to sighted children, children who are blind are reported to explore less often, exhibit less spontaneous play, rarely imitate
their caregiver's routine activities, and frequently engage in solitary play that is repetitive and stereotyped. It has also been suggested that
children who are blind exhibit delays in functional and symbolic play. It has been argued that either fine-motor difficulties or sensory
restriction or both of these might account for apparent delays in developing appropriate play behavior.
Stereotypical play such as mouthing, fingering, waving and banging can sometimes be normal exploratory behaviors for children with little or
no vision, and as such, don't necessarily indicate a problem. In contrast to normal exploration, behaviors such as eye-pressing, body-rocking,
and head-nodding can present serious problems. Such behaviors, which are described as "stereotyped behaviors", "blindisms,"
or "mannerisms," are prevalent among children who are blind or visually-impaired, although they are not found only in this population.
The behaviors usually decrease with age, but can persist to adulthood. Possible reasons for these behaviors include monotony, boredom, stress,
and excitement.
Symbolic play includes pretend play (e.g., pretend eating) and representational play (e.g., using a stick for a spoon). Apparent delays in
development of symbolic play in blind children might be linked to language and cognitive development, or might reflect restricted opportunities
for natural experiences in the world. Many symbolic toys, such as dolls and autos, don't sound or feel the same as the real objects. Thus,
traditional symbolic toys might not be symbolic for children who are blind. Similarly, children typically learn how to pretend by watching
others, but children who are blind are not able to observe how others carry out pretend play-themes. Therefore, it is possible that children who
are blind do not show the same kinds of symbolic play as children who are not blind for reasons other than cognitive development per se.
Intervention and play environment
Interventions suggested to increase functional play and decrease stereotypical behavior (e.g., waving and banging) include teaching different
uses of toys in order to expand the repertoire of children who are blind. It has been suggested that selection of play materials and play
activities should be based on auditory and tactile information. Among recommended playthings are real-world objects such as doorknobs, sponges,
and household items that have tactile appeal and can be manipulated.
Several researchers have suggested modified play environments to enrich experiences and promote learning of children who are blind.
Suggestions include planning play environments to focus on auditory and tactile stimulation, large soft areas so that children who are blind can
tumble about safely, and incorporating tactile maps and cues to facilitate orientation. Some strong cases have been made in favor of specially
designed play areas.
9. Daily-living skills
Self-help
Self-help includes self-care routines such as eating, dressing, toileting and grooming, and also includes skills such as language that are
associated with self-sufficiency. Many self-care skills that are usually learned by observation need to be taught to children who have visual
impairments.
Fine-motor development can affect self-help; for example, self-feeding and buttoning involve fine-motor skills which might be delayed.
Language and social skills are important for self-advocacy and these also might be affected by blindness. Thus, increased opportunity and
intervention to remedy possible delays in fine-motor development, language, and social skills might also enhance acquisition of certain
self-help skills.
Orientation and mobility
Orientation is a process by which position is established within the environment, and mobility is the capacity to move about. It has been argued
that instruction in orientation and mobility does not have a commonly agreed upon foundation. One area reported to illustrate the lack of
agreement is instruction in long-cane technique. Long-cane technique has a history of more than 40 years, and the cane is likely the most common
mobility aid. However, the scientific basis of long-cane technique is poorly developed, there is no systematic theory on which to base training,
and approaches to training in long-cane technique vary considerably.
Although orientation and mobility training for preschool-aged children typically includes basic skills, pre-cane devices and the long-cane,
researchers are also exploring alternatives such as echolocation, sonar-based aids and tactile vision-substitution. Main findings are summarized
below.
a) Basic skills: Basic skills include sighted guide, protective use of arms, methods to travel in straight lines (e.g., trailing techniques),
and ability to orient in the environment. There is general agreement that instruction should begin when children are very young. However, there
seems to be little empirical work regarding teaching methods, sequence if instruction, or developmental expectations.
b) Pre-cane and long-cane: It has been observed that young preschoolers might not have the maturity to handle a long-cane, yet two-handed
self-protection can be inadequate for obstacles below the waist. Therefore, pre-cane devices such as push brooms, push-broom-shaped devices with
wheels, and hula-hoops have been suggested to facilitate safe mobility for very young children.
c) Pre-cane techniques include basic orientation and mobility skills such as using a sighted-guide, protective techniques, trailing (i.e.,
following a surface such as a wall), and search methods. At one time the cane was only introduced after basic skills were taught. More recently
it has been argued that basic skills should not be considered prerequisites, but should be taught in conjunction with cane instruction.
d) Echolocation and sonic devices: People who are either blind or blindfolded have demonstrated the ability to use natural sound cues to
detect obstacles or to walk parallel to a wall (i.e., echolocation). It is possible that echolocation has under-utilized potential, and
researchers have emphasized its importance to mobility. Findings have been mixed regarding the utility of sonic devices as sensory-aids. Some
electronic travel-aids have proven useful for older children and adults, but the utility of such aids for preschool children is yet to be
established.
School readiness
Researchers have suggested several school-readiness skillsthat are important for children with visual impairments.
a) Body awareness: Body awareness includes knowing parts of the body and concepts associated with body position such as front/back,
left/right, and up/down. By school-age, children who are blind should be able to understand their body position in relation to the environment.
For example, a school-entry skill is to identify location of sounds as front/back, left/right, and near/far, relative to oneself.
b) Listening skills: School-readiness listening skills include ability to follow rules for routine conversation; for examples, turn-taking
and staying on topic. Children who are blind should be able to follow simple oral directions and carry out oral directions using a brailler or a
paper and pencil.
c) Travel competency: The ability to orient and travel in a familiar environment is a general requirement for school. Indicators of this
ability include demonstrations of knowledge of concepts such as in-front, behind, left, and right, with respect to the self and to other
objects, (e.g. being able to locate and use a water fountain.) By about school-age, children who have visually-impairements can be expected to
walk independently to a school or playground within two blocks of home. A school-ready child who is blind should also be able to demonstrate
correct use of sighted-guide technique.
d) Concept development: Six-year-old children who are blind should be able to name shapes, label tastes, and demonstrate basic counting and
sequencing skills (e.g., ordinal positions: 1st, 2nd, 3rd) School children should also be able to name coins and the days of week. In addition,
there are a number of important concepts associated with understanding body-position, orientation, and mobility that are considered important
for school readiness.
e) Competence levels with particular technology: Independent use of a tape-recorder should be demonstrated by the age of school-entry.
Competency with a means of writing braille (e.g., braillewriter, slate and stylus) is necessary for braille users.
There are several optical and environmental (e.g., contrast) aids suitable for preschool aged children that can facilitate effective use of
low-vision. By school age, children should probably be familiar with aids that have been deemed appropriate for them; however, this is not
always a simple problem. Issues include what ages are appropriate for which aids, the need to match aids appropriately to individual needs and
capabilities, and ways to introduce and facilitate their use. e.g., closed-circuit television) Research is needed to investigate the
effectiveness of low-vision aids as a function of vision disorder, and to determine prerequisites for different aids in areas such as attention
control, language, and non-verbal understanding.
f) Braille readiness: Children demonstrating school-ready competency with print or braille should show an interest in books, an awareness of
left-right progression of print, and be able to write their first name, upper- and lower-case letters, and numerals 1-10.
Recommendations to enhance braille readiness include exposure to braille symbols in the everyday environment, practice in tactual
discrimination, and exercises to develop finger and hand dexterity. Practice is needed for skills such as tracking braille dots, handling pages,
and writing braille. As braille reading involves fine-motor skills, early intervention programs need to emphasize fine-motor development.
IV School-Aged Children
The number of children who are congenitally blind is small, and many people have had no contact with students who are blind; thus there is a
typical lack of knowledge of blindness and its implications. The issue is illustrated by a mother's comment that the "difficulties she
encountered in [her son's early grades] ... had less to do with his blindness than with his being the only blind person whom anyone has ever
known." Possible consequences if a teacher lacks knowledge or experience with students who are blind or visually impaired include either
low expectations or no expectations of student performance relative to sighted peers.
It is now generally recognized that students who are blind or visually impaired have unique educational needs. These have been identified as:
concept development and academic skills, communication, social/emotional, sensory/motor, orientation and mobility, daily-living skills, and
career and vocational skills. It is generally recognized that these skill areas are important but there is no consensus regarding the most
appropriate way to meet them.
It has been argued that some needs such as social/emotional and daily-living skills are disability specific, not because of content, but
because of the teaching methods needed. Other needs such as communication and mobility skills involve unique content (e.g., braille, long-cane
technique). Recently, the term "core curriculum" has been used to describe a curriculum to address education needs of students who are
blind or visually impaired. Issues include appropriate school setting (e.g., residential school, day-program, or regular class), ways to ensure
appropriate instruction, and standards for teacher training. National guidelines for education of children who are visually impaired are
available in the United States; however, Canada has no national standards for education in skills specific to blindness. Education in Canada is
provincially based, and Canadian guidelines for education of children with sensory impairments vary according to province.
In the following section, some main areas of need for school-aged children (6 to 12 years of age) are discussed. These are: daily-living
skills, mobility, social/emotional needs, communication, concept development, and academics.
Daily-living skills
The term "daily-living skills" is used here to include skills needed for day-to-day independence, personal care, and self-help skills.
Daily-living skills are involved in routine activities such as dressing, food-preparation and time-monitoring. Self-help involves self-advocacy,
such as being able to ask for assistance when needed. Concern has been expressed that people who are blind or visually impaired can graduate
from high-school with apparently good academic skills yet be unable to carry out everyday routines or care for themselves.
It has been argued that education should prepare students to live as adults; therefore, dressing, handling currency and other daily-living
skills should be included in education programming. In addition to learning functional skills (e.g., signing a name on a credit card), education
needs to ensure that the skills can be applied in real-life situations (e.g., when to use the credit card). Instruction must be carefully
organized so that skills are not learned in isolation but rather in context.
An important part of self-advocacy is ability to describe needs and respond to other's questions. In one study of 6-16 year old children with
visual impairments, less than half could name their visual impairment, and few could state which part of their visual system was affected.
Researchers recommended encouraging conversations among children, parents and doctors, and preparing children for questions about their eyes
from classmates and strangers. It has been suggested that children should be given factual information in age-appropriate vocabulary and that
children be instructed so that they can assume full responsibility for accurately answering questions.
1. Mobility
The variety of possible travel-aids that might be appropriate for school includes trailing techniques, the long-cane, sighted-guide, and
electronic travel-aids. A hula-hoop has been suggested as a pre-cane mobility-aid for kindergarten and first-grade. There appears to be little
or no empirical evidence relevant to determining which aids are most appropriate for particular age groups. Neither does there appear to be much
empirical investigation pertaining to possible instructional methods; however, the ability to use and direct a sighted guide is likely
indispensable for integrated activities.
It has been suggested that balance activities might be important for promoting gross-motor development in children with impaired vision, and
the importance of balance instruction likely increases as vision impairment increases.
2. Social/emotional needs
Peer-interaction and play-behavior
Preschool children with visual impairments have been observed to be segregated and socially isolated from peers. Researchers suggest that
intervention is needed for school-age children so that these patterns don't continue at school. There is speculation that social isolation is a
function of delayed development of those aspects of social understanding that enable social inferences, perspective taking, and problem solving.
Teachers also might inadvertently contribute to segregation by arranging classroom seating in ways that discouraged peer interaction, and by
removing students from regular classroom activities to provide special education services.
Studies have shown that students with visual impairments initiated and participated in interactions less frequently than their peers with no
visual impairment. Interestingly, 15% of the classroom teachers perceived that the students with visual impairments interacted with peers more
frequently than other students did. Social interaction should be explicitly encouraged through cooperative learning activities, and by providing
special education in ways that includes participation of students with and without impairments. Research suggests that play-environments be
designed to increase activity of children who are blind, thereby increasing learning experiences. Some suggestions are to include real-world
things suitable for tactile exploration (e.g., doorknobs, turnstiles), large soft areas for safe gross-motor play, and to incorporate complex
designs in the play-environment.
Self-esteem
Research in the area of development of self-esteem is controversial. Some researchers argue that children who are blind or visually-impaired
have either normal or high self-esteem, and that there is little evidence that children who are blind have consistently lower self-esteem than
sighted children. Others take a different stance.
3. Communication
Reading and writing
There is evidence that children with visual impairments were disadvantaged in reading when compared to their sighted age-mates, and that the
visually-impaired children's disadvantage in reading increased with age. Choices of media for reading and/or writing include large print,
braille, modified print or braille, and magnification devices (e.g., CCTV). Factors that can influence which media are selected include eye
condition, physical dexterity, availability, and teacher attitudes. Researchers suggest that either braille or large print might be dismissed
too quickly when one could be a viable option. Current research is examining the selection of appropriate media, and exploring options and
issues in a context of ever-changing technological advances.
Braille
Reports show a range in speed of braille reading with good comprehension. In one example, the average high-school-aged braille reader was found
to read about 100 words per minute (wpm) compared to an average sighted reading rate of more than 250 wpm; however, the rate was less than 40
wpm. for 40% of the group of braille readers
It has been suggested that braille letters have fewer distinguishable features than print counterparts; therefore, braille letters might be
more easily confused than print which might contribute to apparently slow braille-reading rates. Factors associated with relatively faster
braille-reading rates include two-handed reading, light pressure, and smooth horizontal hand movements.
The prevailing view is that braille skills should be introduced in preschool. Researchers have pointed out that braille is increasingly
under-utilized, and that relatively little time is devoted to braille instruction and practice. Findings from applied research could contribute
to developing standards for braille learning. In particular, research is needed to establish what should be expected with respect to braille
acquisition and competency.
4. Cognitive development
Vision provides an important context for interpreting information from other senses; therefore, lack of vision also means a lack of relevant
contextual information. An important implication for parents is to provide both a context for sounds and a description of related events for
children who are blind. For example, if a parent hammers a nail into a wall a child who is not blind might see the hammer, the nail, the wall,
and observe an entire series of inter-related events, but a child who is blind might only hear the sound of a hammer striking a nail. It is
suggested that adults provide descriptions of events to help a child who is blind gain meaning from what might be otherwise chaotic sensory
experiences.
A general issue relevant for school aged children is the possible impact of vision impairment on areas of cognitive development that are
associated with interpreting information available to the senses. Examples of such areas are classification, conservation, spatial knowledge,
and memory.
Classification
Research using classification tasks found that children who were blind showed a delay in acquiring relational concepts (e.g., in-front-of,
behind, beside, and between) and had difficulty with abstract concepts (e.g., tall, colored). The reason might originate in limitations of
tactile experience, which can impact development of classification skills for blind children.
Conservation
The term "conservation" refers to the understanding that properties of matter such as mass, number and volume are retained (i.e.,
conserved) despite changes in appearance. An example is knowing that water can maintain the same volume even if the shape of its container is
changed. Findings have been mixed with respect to whether or not there are delays in conservation.
Spatial knowledge
Spatial knowledge includes concepts such as in-front-of, between, behind, above and below as well as knowledge about environmental layout and
object structure. Spatial knowledge and spatial reasoning are important for tasks such as way-finding, map-tracing, and putting together
multi-piece objects.
Researchers investigating effects of vision loss on spatial knowledge have generally found that children with visual impairments do not
perform as well as their sighted peers. Performance improves as a function of increasing age, delayed onset of vision loss, familiarity, and
proximity (near-space tasks are easier than far-space tasks). Children who are blind have been found to exhibit delay in acquisition of
relational concepts, such as in-front-of, behind, beside, and between. However, not all researchers have found performance decrements across all
tasks.
A general issue in explaining performance deficits associated with children who are blind or visually impaired is whether they represent
spatial knowledge differently than children with good vision, or whether their knowledge is simply manifested differently as a function of
limited visual experience. If a performance deficit were due to limited experience, an implication would be that facilitating or increasing
relevant experiences could remediate the deficit. If knowledge is represented differently, an implication is that the same kinds of errors would
be maintained whether or not tasks or environments were familiar.
There is some evidence that people who have no vision develop ability to use sound cues more accurately than people who have partial vision.
Such ability is important for localizing and using landmarks. However, stable landmarks are fewer and landmark information is generally less
reliable for persons who are blind relative to those who are sighted. Thus, in general, children who are blind experience more difficulty than
sighted in learning both Euclidean (i.e., straight line) and Route knowledge. Therefore, although children who are blind might be able to
navigate accurately within a familiar environment, their knowledge of the relations among objects and landmarks might be less precise than that
of their sighted peers.
Researchers have suggested that tactile maps could assist blind children to better understand their environment. One implication is that maps
should be used in mobility training, for which landmarks and knowledge of environmental layout are important. Research in the area of map usage
is sparse; however, some findings indicate that effective use of tactile maps might help compensate for limitations of visual experience.
Effective tactile-map training, applications of maps for enhancing spatial understanding, and investigating the kinds of haptic information and
haptic exploration patterns that are most useful to replace visual information about objects are all areas for further study.
Perspective taking
Lack of vision can result in impaired understanding that an object will appear the same to another person if viewed from the same position, but
can appear differently to a person viewing from a different side. Therefore, children who are blind might have great difficulty inferring what
another person can perceive. By school age, children with and without visual impairments know that others have internal experiences of seeing
that are independent from their own. School-aged children who are blind know that sighted persons do not have to touch things to see them, but
have difficulty determining what sighted persons can or can't see.
V Needs of families
Congenital blindness is a low-incidence condition, causes of blindness and visual impairment are numerous, and there is a high incidence of
concomitant disabilities. Thus, the population of preschool children who are either blind or visually impaired is both small in number and
heterogeneous. One implication of the small number is that parents might have little or no prior exposure to visual impairment. Moreover, they
might have no contact with other parents whose children have the same vision condition. Therefore, it is very likely that parents will be unable
to rely on their experience to guide their expectations of their child's development. An implication of the heterogeneous nature of the
population is that the impact of visual impairment and associated issues differs markedly between families. Difficulties experienced by parents
whose babies are congenitally blind can differ considerably from those of parents whose young children or infants become blind from injury or
disease. It has been argued that is not possible to provide clear-cut guidelines regarding what might arise, or how to deal with the effects of
visual impairment on either the child or family. Nevertheless, some generally defined issues can be addressed.
A general need for families of children with visual impairments is information. This includes information about their child's vision
condition, general information regarding blindness, and ways to promote and enhance their child's development. Other main needs are emotional
support and guidance, assistance with learning about and accessing resources, and advocacy.
Information about their child's particular vision condition
Parents need information so that they can understand their child's particular vision condition, its prognosis, and its implications.
Understanding is important so that parents can deal with their children's individual needs, help their children achieve to potential, and be
effective advocates in order to maximize opportunities for personal and educational growth. It has been suggested that support and services must
start before an accurate diagnosis or assessment is finalized in order that children who are blind or visually impaired do not lose out on the
benefits of early intervention.
General information regarding blindness
Parents need information to deal with issues associated with their child's development, orientation and mobility, short- and long-term plans,
and integration in the school and community. Among other issues, it appears that general information regarding blindness and visual impairment
remains an outstanding need for parents.
Information regarding how to promote their child's development
Parents need information and assistance to help their children compensate effectively for the limitations on experience imposed by blindness.
Issues for parents include communication with their infants, and ways to enhance experience and promote development. Unlike sighted children,
who communicate with eye contact and smiles, children who are blind have been observed to use hand-movements and other body-cues to indicate
what they noticed and where their attention was focused. Parents whose children are blind need guidance as to how to interpret their children's
body-language.
A number of sources discuss issues and suggestions regarding areas such as early development, early-intervention, daily-living skills,
language development, and school readiness. One suggestion is to explain context and antecedent events for children who are blind or visually
impaired. Thus, rather than announcing "Here's juice," parents might say, "Hear this? I'm pouring juice in cup, now I'm putting
it on table in front of you." Providing a context provides a child with an opportunity to understand what otherwise might be available only
through vision.
Those who stress early intervention warn that children who are blind or visually impaired could lose out on opportunities and exhibit
developmental delay if parents do not receive appropriate support from qualified child development specialists with expertise in blindness.
Information regarding educational needs and educational expectations
It has been recommended that parents take an active role in monitoring academic progress and be child advocates. Parents need information with
respect to their children's unique educational needs, performance benchmarks and guidelines so that they can be effective participants in their
children's education and make informed decisions regarding their children's educational services.
Emotional support and guidance
Researchers point out that although certain issues are specific to individual situations, most parents undergo similar experiences with respect
to adjusting to their child's visual impairment. Parents can experience emotions which need addressing such as grief, guilt, denial, and anger.
In addition, parents and children need guidance to deal with their own and others' expectations, attitudes, and knowledge gaps. It appears that
many parents are not receiving necessary emotional support and guidance, and many parents might benefit from referral to counseling, peer
support, or resources to assist them with dealing with their child's diagnosis.
Advocacy and assistance in accessing resources
There have been several efforts to compile information and list resources to assist families; however, many families are not accessing necessary
information and resources. Clarification of specific services available, the participation in support groups, needs for advocacy, and assistance
in accessing resources for support and education recur as themes, and these remain among the most important needs for families.
More generally, normalization, empowerment, and enablement must be the goals of advocacy, which directs the provision of equitable services,
experiences, and opportunities in order to empower and enable people who are blind or visually impaired to live self-directed, meaningful lives
of independence. It is critical that these goals are introduced into the lives of children who are blind or visually impaired children early as
possible in order to ensure maximally effective patterns of adjustment to their sensory impairment.