University of Edinburgh

Tactile Graphics

CHAPTER NINE: The importance of these observations for education

9.1 Recommendations for the design and use of tactiles

For ease of storage, durability, and freedom from floppiness during use, thermoformed diagrams should have as shallow relief as possible, given the demands of the subject matter. Nevertheless, many diagrams will need a bolder, multi-layer treatment in order to carry the desired picture content.

The diagram formal should be uncluttered. All unnecessary detail should be omitted, but where less important material has an educational or informative value, the possibility of conveying the information through more than one diagram should be considered. For example, in a histological illustration some secondary detail may put the tissue which is the main purpose of the illustration into a more realistic context, and to omit it altogether would be misleading. In such a case a second illustration showing the main subject in bolder detail or more magnification may be advisable.

In all types of diagram the writer has often observed that blind users are helped by the presence of more frequent points of reference than would be necessary for a sighted person. Examples of this would be the scale markings on a graph, or grid markings on a map. If these are too widely separated from the operative part of the diagram it becomes difficult for a blind reader to correlate the two features accurately. On the other hand, it is important that extra information like this should not add to the general clutter or distract the reader from the primary purpose of the diagram.

Applied textures should be natural and appropriate to the subject, since the blind person may need to relate the picture to something experienced in real life.

The spacing of diagram components should be adequate for discrimination unless different textures reinforce this. It is not helpful to lay down hard and fast rules for the spacing of components as some map-makers have been inclined to do, because the resulting perception is shaped by the overall context of the display, and the way the various components interact. 

Since Braille is a major limiting factor on any diagrams which are intended to carry Braille annotations, such designs must be worked out with the space required for the Braille and the need for unobstructed Braille reading kept firmly in mind. Whenever complex Braille labelling, supplementary notes or scanning directions are required, the provision of such instructions via supporting audio files should be considered. (Hinton, 1988a, p 13)

For more advanced work, great care should be taken when a tactile diagram or flow chart spreads over to several pages. There is great danger of disjunction of information when this happens, and students using this kind of diagram may find effective study difficult. To counteract this, the related pages should be carefully cooordinated, with all interrelated information being adequately cross-referenced. Particular care should be taken with mathematical information in such circumstances, because this may be misread or overlooked by the student in making calculations.

Microcapsule paper diagrams have a valid educational use, and their effectiveness should not be underrated, but it is vital that they are only used in conditions where educational considerations, and not convenience, dictate their use (as with all diagrams).

Satisfactory microcapsule diagrams can be produced with an ordinary photocopier, followed by radiant heat treatment, for which the author's research unit usually employs a Ricoh fuser which originally, from an off-set lithography installation.

There is clearly the potential for more widespread use of the more pictorial forms of tactile display, and with these any suggestion that can be given of 'the third dimension' will help the blind user to understand the message of the picture, Where scenic types of picture are transcribed into tactile form, perspective phenomena will be encountered, and these are outside the direct experience of congenitally blind people. Where perspective can be avoided in teaching diagrams it is better omitted, but where it is necessary for a blind reader to come to terms with it, this can be accomplished initially within a meaningful picture context. Auditory analogues which the blind person will have experienced are useful in explaining perspective effects. (see Section 5.3) Only at a later stage, depending on the maturity of the student and future study needs, is it wise to embark upon an academic explanation of perspective geometry.

9.2 Educational environments which engender success

It is especially important that blind pupils encountering tactile diagrams should be at ease and should not feel threatened by the experience. Such students often feel that features of their lessons are set up with the intention of testing their intelligence. They may have experienced failure on previous occasions, and do not want to find themselves in any situation where they do not feel entirely in control. Rather than be speculative, they would prefer to wait to be told the 'correct' answer, which they are happy then to remember and reiterate. If the above sentences sound condescending to the pupils concerned, this is unfortunate, because they are intended to criticise the educational environment in which they are often reared, and not the pupils who have to endure it.

Tactile diagrams, maps and pictures do not always have to be presented in this didactic fashion. They can be an important extension of the outside world, waiting to be explored. It is this exploratory attitude to diagrammatic material which needs to be fostered. Wherever possible, the pupil should be encouraged to search for the available information within the diagram or picture. If this is not apparent, the pupil should feel free to ask for help and further information from the teacher, without feeling a sense of failure. Indeed, older pupils should be aware of the possibility of an inadequate diagram. (Hinton, 1988a, p 15) Knowledge gained in this way can generally be remembered, and experience with this way of studying will not only have its immediate reward in terms of what is understood from the diagram under scrutiny, but every diagram experienced in this way helps the pupil's preparation for more advanced material later in life, and lays a good foundation for secure independent study and personal research. The writer has seen ample evidence of this in working with individual children over periods of several months and in some cases for two or three years during research described in this book.

The word 'diagram' in this instance is intended to include the whole integrated package of picture, Braille caption and supplementary text.

9.3 What kind of educational programme is required as a preparation?

This section describes some ways in which the element of the child's educational programme can be developed and the implications of some of its components. These are suggestions which are not intended to be prescriptive, but can be adapted to fit individual learning needs, or the individual teaching styles of teachers. They can also be taken out of order in response to a particular learning need, as long as the general progression of activities is preserved.

Firstly, the blind child needs active exploring and handling experience from infancy. The live experience illuminates the diagram; the diagram may later help to explain the live experience. This activity is particularly important if the child shows a tendency towards undue passivity when young. It may be necessary to provide extra encouragement and stimulus to break out of this state in an environment which feels safe.

Parents and teachers need to communicate some of the excitement and interest of finding out things, and sharing experiences. Most teachers who are trained as visual impairment specialists will do this as a matter of course, but some have greater success than others. It is perhaps another example in education where it is better to drink from a running stream than a stagnant pool; teachers who are prepared to learn and discover for themselves, far from losing face in front of their pupils, often teach best. Their attitude is apparent even to the very young child.

It is important for teachers to make every possible use of analogies meaningful to a blind child in discussing everyday phenomena which are visible to the child with full sight, but outside the blind child's direct experience. To take as an example: A six-year old anophthalmic child in a mainstream primary class had been discussing falling rain and its importance as a source of streams and rivers with the members of her class. The child had, of course, never seen raindrops coalescing on a window-pane to produce a trickle, which was the starting point of the discussion for the other children. In this case the following 'model' was devised from apparatus already in the classroom:

A large bean-bag type cushion was rested partly across the child's knee with the child squatting on the floor. Under one side of the cushion a large plastic tray was placed. The child was then provided with a container of glass marbles which were to be used as 'raindrops'. The child was encouraged to drop the marbles slowly, one by one, onto the nearest half of the cushion. Each marble fell with an audible thump onto the fabric of the cushion.

At first the 'raindrops' were isolated, so no further sound was heard. However, after a while one of the marbles eventually hit another with a glassy click, and this soon became a frequent occurrence. (In fact it was possible for the child to say from the sound whether the marbles bounced apart or remained in contact.) At each stage careful exploration with the fingers would verify the arrangement of the marbles, taking care not to cause a disturbance. The teacher/researcher then suggested that a similar fate would befall a succession of raindrops. Eventually little rows or 'trickles' would be formed.

Sooner or later a long trickle would weigh the filling of the cushion down, forming a tiny valley, and this would eventually cascade off the side of the cushion with a vigorous rattle into the plastic tray.

The marble analogy was reinforced by running water from a beaker into a sloping tray of sand. The blind child could now follow this as well as a sighted child would, but was able to feel damp patches and hollows in the sand and to feel the tiny valleys and meanders created by the water flow. It was necessary for the child to explore this with care and delicacy to avoid destroying the evidence.

Tactile presentations on the page can include both pictorial and map-like formats from an early stage. Pictures should be bold, simple and in fairly deep relief to begin with, so that the comparison with the object portrayed is obvious. With increasing experience the relief can be reduced a little.

Mapwork should begin on a scale which allows the environment depicted to be encompassed by the child's two hands so that there is no abrupt change of scale in moving from environment to map. This has been discussed in more detail in Chapter Four and in the simple introductory strategy described in Yngstrom's writings. (Yngstrom, 1988) From these early beginnings maps can increase in size and complexity, but should always be backed up by on-site experience so that the child builds up an understanding of how things are depicted on a map. The 'site' can of course be a model if this is more convenient. Simple spatial exercises are helpful in developing directional sense and an understanding of the relationships of objects in space. As pupils reach the stage of predicting the environment from a map, Yngstrom's strip method for orienteering maps (Ibid, p 11) seems an appropriate way of providing a clear linear pathway which minimises distractions, and focuses attention on the essentials.

Pupil drawing on German film or Melinex is a helpful way of developing skills with maps, (Ibid, p 2,3, & 5) geometrical diagrams and life drawings. In geometry, finger tracing should be encouraged before pen drawing is attempted. In the absence of visual feed back the blind pupil needs to develop a repertoire of kinaesthetic shape drawing experience to be able to draw fluently. This approach is also important when moving on to solid shapes. In order to understand the idea of drawing a single 'viewpoint' the congenitally blind child needs to outline with a finger the shape which corresponds to a particular sight line. A blind child of average intelligence in Year 2 can understand the aspects of simple shapes like a rectangular box or a cylindrical cocoa tin.

Pupil drawing is also beneficial in dealing with items drawn from life (eg; objects from 'the nature table' and other found objects). Although the teacher may draw for the pupil so as to demonstrate the style of line drawing and its use for illustrations of this kind it is important that the pupil's final drawing is made from the object itself.

With such subjects and with environmental layouts all possible transcriptions of the subject should be experienced. For example: From the explored environment the pupil should try to produce a model in some suitable medium such as Lego bricks, cardboard boxes or clay. From the model a map can be drawn. Later, perhaps, the map can be drawn directly from the environment, initially from general impressions and later from measurements. Conversely a model could be built from the map, or the environment could be predicted and explored with the aid of the map. It should always be the aim of the teacher to offer a stimulating context for the task which is being proposed. For example, the task may be presented in the form of a puzzle which may require the pupil to rearrange components according to a given plan.

It is found that drawing and modelling exercises are not just an end in themselves, but that the pupil is stimulated to explore the real object or environment more carefully and critically in order to produce an accurate model or drawing.

At appropriate stages more and more detailed information can be sought from the maps and diagrams so that the pupil accumulates greater skill. The significance of viewpoint for the sighted person should emerge in a natural way early in the blind child's learning with pictures. It should certainly not be taught in an academic fashion even at the secondary school level except where this information is required for the pupil in a technical subject.

9.4 Measuring and mathematics

Measuring has already been mentioned and should begin in a simple way in year 1, with techniques being gradually extended as understanding grows. It must be noted, though, that tactile measuring devices in some cases have weaknesses and inaccuracies which are built in to the apparatus. These not only create problems for the pupil, but also place restrictions on the tasks which the teacher can prescribe. With blind pupils it is especially important to develop skills of rapid measurement. Pupils must be taught to read along the largest possible units as quickly as possible and only at the end to count the finer graduations for an accurate measurement. For example, when making length measurements with a metre stick, there is a tendency for the blind pupil to count laboriously every centimetre, instead of rapidly scanning the decimetre and 5 cm graduations as far as possible. Failure to use the latter strategy makes a slow task even slower.

There are problems for blind children in dealing with the measuring tasks found in mainstream maths books when the tactile measuring devices available to them may not have the finer graduations. For examples, a tactile protractor commonly measures to the nearest 5 deg and a tactile ruler to the nearest 5 mm and not to 1mm. This means that a lesson development that may seek to integrate the pupils knowledge of units of length with developing knowledge of decimal place may be impossible. Individual millimetres are not available to the pupil and metres are so large as to be difficult to manage.

The writer has taught the beginnings of decimal place notation to 6-7 year-olds by using an invented unit of length (named after one of the children). Not only could several of the 'whole units' be kept within the span of two hands, but the 1/10 unit tactile division was large enough to be detectable. This kind of strategy may sometimes be necessary to overcome some of the practical manipulative problems. At the same time much of the standard apparatus for practical maths at Primary level can also be used by blind children.

In mathematics and in dealing with all quantitative information, pupils should experience all the usual forms of graphic display such as histograms, line graphs and pie charts, and should learn how to read quantities and coordinates from these. As has been mentioned before, blind users often need more points of reference than a fully sighted person would, in order to orientate themselves. Some information will be better presented in a model or a microcapsule diagram.

With all types of tactile diagrams and pictures it is important that users learn scanning techniques, beginning with a light, cursory sweep before more detailed examination. When diagrams fail for a blind student it is important that the diagram itself should be examined critically to see if it is deficient in any respect, but it is also vital to consider whether the student's preparatory experiences were lacking in any detail.

9.5 Educational provision for advanced study

In secondary and further education it is important that blind students have tactile versions of anything shown on the blackboard or overhead projector. This needs to be provided at least when the visual presentation is made, and preferably before the lesson to give the student an opportunity to preview the tactile presentation so that the lesson points can be followed with reasonable fluency.

At this educational level there must be very close cooperation between course lecturers and those responsible for the provision of tactile resources, or the resource staff must have an intimate knowledge of the content and intentions of the course.

The provision of tactile resources is never adequate if the resource staff are relegated to the role of 'jobbing printer', merely transcribing into strict tactile copy every feature of print handouts without question.

9.6 Introductory material for older students

One of the problems with adult blind students is that their educational experiences will have been very varied and particularly where tactile diagrams are concerned, their previous experience may be very limited or non-existent. However adequate it may have seemed at the time it may have happened before recent developments of relevant technology and its application.

Because of this, adult blind students may be offered tactile presentations which they find impossible to understand. The conclusions most frequently drawn in these circumstances are either (a) the diagram is no good, or (b) the student is incapable of using such material. In fact, the most likely explanation is that the student has not had the benefit of appropriate introductory material to develop skills of exploration and interpretation.

In these circumstances, students may be inclined to 'switch off' mentally when first presented with tactile diagrams. It is therefore important that an appropriate introductory study pack is provided when required. This would cover the various kinds of mathematical representation which may be important (eg; line graphs, histograms, pie-charts etc) and common map and diagram types in simple form. It should also present simple exercises in obtaining information from such displays.

The student also needs experience of the likely position of Braille titles, labels and other instructions, and practice in the use of Braille and textural keys. 

9.7 Scenic presentations

Tactile depictions of scenes, as distinct from isolated objects, arc still comparatively rare, and greater use of these could be made in the future. Congenitally blind users will not have had prior experience of any of the phenomena of visual perspective. They will not have experienced the occlusion of one object by another standing in front of it. They will not have experienced the apparent upward movement of an object in the visual field with increasing distance, and the way this affects groupings of people and objects in pictures. They can learn to understand these phenomena, but not usually in the vivid way in which the TVSS subjects experienced them in controlling their own camera. (Guarnerio, 1974, p 103) An older user of scenic tactiles can go on to understand perspective phenomena in a more precise way, and begin to appreciate them as a source of absorbing interest and challenge to many visual artists.

When attempts are made to transcribe visual art into tactile form for the enjoyment and education of interested blind users, it is the writer's strongly held belief that the tactile pictures should at least hint at style differences between one artist and another.

The blind person would get a very false impression if human figures by, say, Gainsborough, Monet and Stanley Spencer appeared to have the same solidity. This intention is undeniably problematic, but if it cannot be attempted, then the tactile page remains as a very superficial kind of map, and it would perhaps be preferable to rely on the evocative power of words instead.

9.8 The overall picture

Tactile diagrams and pictures are still sorely underused in the education and leisure pursuits of blind people. It is true that first hand experiences are vitally important wherever they can be provided, but tactile pictures fill in many unattainable gaps. Many things are too large, too small, too fragile, or too dangerous to be touched and it is in situations like these that models and tactile pictures come into their own. Tactiles provided in early life also prepare the user for later, more detailed material. There is a need for home-based activities which contribute to the developing corpus of understanding.

Media like German films need to be more generously provided for the child to experiment with, for 'practice makes perfect' and only by experimenting and making mistakes in solitude will the blind child acquire fluency in reading and drawing tactile pictures.

It is also possible to create diagrams and pictures which have a game or puzzle element and can be used as the starling-point for practical activity. There are many possible uses for such things as tracking and discrimination tasks, counting and shape matching games, and so on.

One congenitally blind six-year old in a mainstream class needed some kind of apparatus to give her some idea of snow-crystal forms when her sighted peers were looking at photographs etc. She was provided with a six-fold star-like shape of thin rods spaced at 60 deg intervals. This was then thermoformed in heavy grade pvc and used as the basis of a snow crystal shape which she built for herself out of small rod-shaped or v-shaped sub-units of white plasticine. She was told that any unit which she added to the first rod (generally the top one) should be matched by identical additions to the other five arms as in the diagram opposite. She in fact prepared six identical pieces of plasticine which she rolled and shaped before laying them in position on the matrix provided. The finished model exhibited the six-fold symmetry which is characteristic of snow crystals, and formed an acceptable alternative to the visual experiences and drawings of her peers.

9.9 The future for tactile illustrations

With present knowledge and equipment it has to be admitted that the available tactile illustrations fall woefully short of the capabilities and variety of visual illustrations. Despite this, the various sorts of tactile presentation have advanced greatly in the past two decades, and teachers and others working with visually impaired children and adults are learning how to make better use of them.

In an era when the world of technology becomes more and more complex, and where communication, whether for education, information or entertainment, becomes more visual, it is vital that the means are found to make as much of this material available to visually impaired people as possible. This is particularly so where visually impaired people are supported in a setting where they are integrated with sighted people. A failure to do this would further handicap them in education and career opportunities and in leisure and entertainment. Fortunately for the future, even the present methods of provision have not yet been fully exploited, and some present work gives hope of imminent advance

The research of the present writer has made it clear that even congenitally blind people can learn to use tactile graphics, and that their responses can be quicker and more complete than some teachers have suggested. Their enthusiasm and enjoyment in doing so is likewise heartening.

Ron Hinton
First published 1996
ISBN: 0901580775