DESIGNING WITH AND FOR THE VISUALLY IMPAIRED:

VOCABULARY, SPELLING AND THE SCREEN READER

∗

Verena Stein, Robert Neßelrath, Jan Alexandersson and Johannes Tr¨oger

German Research Center for Artiﬁcial Intelligence - DFKI GmbH, Saarbr¨ucken, Germany

Keywords:

User-centered design, e-Inclusion, Computer-assisted vocabulary learning, Visual impairment, Auditory feed-

back, Vocabulary acquisition, Orthography.

Abstract:

For visually impaired people it is both usable and effective to study foreign language vocabulary and spelling

with an auditory e-learning device. Amongst visually impaired computer users there is a growing preference

for the screen reader over the braille line. Unfortunately, this exposes them even less to the written word.

However, spelling is considered one of the biggest challenges for visually impaired people who study a foreign

language. Existing computer-assisted vocabulary learning software is often designed for sighted users and

information is lost when they are accessed with a screen reader. This paper discusses the successful evaluation

of a prototype of an auditory vocabulary and spelling trainer (AVoS) and explains how essential it is to involve

the target group in the development process. The paper presents the results of an online survey amongst 88

adults with visual impairments in Germany. The survey clearly indicates who would beneﬁt from an auditory

vocabulary and spelling trainer and which features would make it usable.

1 INTRODUCTION

Reading text on the screen is not the same as having

it read aloud by text-to-speech technology. While the

content is available in both cases, orthographic infor-

mation is lost when text is read by a screen reader.

This is disadvantageous to visually impaired people.

In the second language (L2) classroom, especially

spelling is often challenging for the visually impaired

(Couper, 1996), (Moodley, 2004), (Nater and Th¨ale,

1994). For sighted people it is easy to encounter writ-

ten words in a foreign language. A learner of En-

glish, for example, can choose from a great selection

of printed learning materials, they can read newspa-

pers and books, and have access to English websites.

For the visually impaired, however, this is a differ-

ent story. Materials in braille are expensive as they

need to be printed with special printers. Due to the

limited demand, not everything can be converted to

braille. When it comes to language learning, Bogus-

law speaks of a “great shortage of materials suitable

for learners requiring non-visual methods” (Bogus-

law, 2000, p. 1). Computer technologies are hence

∗

This work has been funded by Kohlpharma GmbH. The

opinions herein are those of the authors and not necessarily

those of the funding agency.

a true blessing for those with vision problems. With

assistive technologies such as a screen reader or a

braille line (device displaying embossed writing), vi-

sually impaired people can access a great deal of

internet content and software applications just like

sighted users. However, the screen reader is com-

monly perceived as more usable than the braille

line because it is faster and requires no extra hard-

ware (Moodley, 2004). This creates a dilemma:

visually impaired users have difﬁculties spelling in

a foreign language yet they often access foreign

language in a way that hides spelling. What is

more, computer-assisted vocabulary learning (CAVL)

software—as a way to speciﬁcally address ortho-

graphic shortcomings—is often designed for sighted

users. So whether CAVL programs are accessed with

a screen reader or a braille line, the user experience

for the visually impaired is altered. Shinohara has

analysed how blind persons interact with technology

and ﬁnds that “[...] functional equivalence might not

account for the meaning of the mode of interaction

for particular users of speciﬁc contexts.” (Shinohara,

2009, p. 66).

This explains the need for a customised CAVL

software that focuses on two important aspects for

visually impaired language learners: (1) usable ac-

462

Stein V., Neßelrath R., Alexandersson J. and Tröger J..

DESIGNING WITH AND FOR THE VISUALLY IMPAIRED: VOCABULARY, SPELLING AND THE SCREEN READER.

DOI: 10.5220/0003480804620467

In Proceedings of the 3rd International Conference on Computer Supported Education (ATTeL-2011), pages 462-467

ISBN: 978-989-8425-50-8

 2011 SCITEPRESS (Science and Technology Publications, Lda.)

cess mode, that is, have a primarily auditory output

and an optional braille output, and (2) efﬁcient learn-

ing strategies, that is, focus on L2 vocabulary and or-

thography. Just how would a CAVL program teach

spelling via the auditory channel? Is this perceived

as usable by the target group? Following a user-

centered design approach, AVoS, an auditory vocabu-

lary and spelling trainer, has been developed, yielding

very promising results in a ﬁrst prototype evalution

(Stein et al., 2010). It highlights orthographicalerrors

through means of prosodic enhancement. To ensure

usability for the target group, they have been involved

in the design process.

This paper motivates the development of AVoS by

providing a clear proﬁle of the needs of the target

users. Section 2 describes the situation of visually

impaired CAVL users from a didactic and usability

point of view. Section 3 discusses the methodology

adopted in the development of AVoS in which the tar-

get users play a central role. Section 4 presents the

results from a ﬁrst prototype evalutation and from an

online user survey conducted amongst 88 visually im-

paired adults. Section 5 concludes the paper by sum-

marising the main results and providing insights for

future research.

2 MOTIVATION

This section describes which features make a CAVL

program successful for language learners, especially

when they are visually impaired. It further discusses

didactic and usability aspects, hence justifying the

central importance of involving target users in design

process of an auditory CAVL tool.

2.1 Computer-assisted Vocabulary

Learning for the Visually Impaired

Explicit vocabulary study is an efﬁcient way of in-

creasing proﬁciency in a foreign language (Laufer,

1997), (Nation and Newton, 1997). It allows to

study form and meaning of words simultaneously.

This method allows to deﬁne a clear learning goal

and measure progress—two features that keep the

learner’s motivation high, as demonstrated in various

studies (Bandura and Cervone, 1983), (Lord, 1982).

Moreover, explicit vocabulary study allows to repeat

words in spaced time intervals in order to ensure long

term retention (Ebbinghaus, 1885), (Pimsleur, 1967).

A model that allows for this type of explicit vocabu-

lary study is Leitner’s “hand-computer”, a comparted

box with ﬂash cards. The target language is written on

one side of the card, the deﬁnition on the other side

(Leitner, 1972). This model works well for all lan-

guage learners and there are various CAVL programs

that make use of this system such as Phase 6 (Gorin,

2011) or Vokker (Vokker, 2010). There are even pro-

grams that are speciﬁcally designed to be used by vi-

sually impaired users such as the vocabulary trainer

recommended by the German braille line manufac-

turer Papenmeier (Papenmeier, 2011). However, all

programs that have been reviewed by Stein (Stein,

2010) have one of two shortcomings. (1) Contents

and learning strategies: spelling—as an integral part

of vocabulary study—is not addressed adequately. (2)

Navigation and usability: the program is not screen

reader friendly or not usable when the output mode

auditory. Subsections 2.2 and 2.3 discuss these issues

in more detail.

2.2 Didactic Aspects

Learning vocabulary requires mastering a word’s

meaning, form and use (Nation, 2001, p. 27). As

was discussed earlier, especially learning the ortho-

graphic form of a vocabulary item can be problem-

atic for visually impaired people. First, they are not

exposed to the written word as much as sighted lan-

guage learners. Second, CAVL tools do not ade-

quately address the issue of spelling. There is a ten-

dency to relate orthography to reading and approach

the spelling task from a visual point of view. This

is reﬂected in the visual nature of orthographic feed-

back in many CAVL applications. Speciﬁc errors are

usually pointed out visually (Stein, 2010). There is

evidence that this might not always be the best way.

Shuren found that “written and oral spelling share the

same central processes [...]” (Shuren et al., 1996, p.

52). This means that whether one reads a word or has

is spelled out orally, the same parts of the brain are

activated. Bosman et al. suggests that oral spelling

might be superior in the spelling acquisition process

(Bosman and Orden, 1997, p. 10). Arter et al., who

more speciﬁcally discuss the issue of spelling for chil-

dren who have visual impairments, come to a similar

conclusion, stating that “[f]or blind children and audi-

tory approach would be more appropriate” (Arter and

Mason, 1994, p. 20). Other studies discovered that

spelling and phonetical awareness are closely related

(Bosman and Orden, 1997), (Katz, 1989). This means

that spelling errors are usually phonetically plausi-

ble. Moreover, in order to spell correctly in a foreign

language, one needs to have phonetical awareness in

that language. A study by Thomas and Dieter reveals

that the best practice for acquiring good orthographic

knowledge is writing correct words (Thomas and Di-

eter, 1987). The interactive nature of a computer pro-

DESIGNING WITH AND FOR THE VISUALLY IMPAIRED: VOCABULARY, SPELLING AND THE SCREEN

READER

463

gram allows to practice writing words and can give

immediate feedback in terms of orthographic errors.

From what has been discussed above, it seems sensi-

ble for this feedback to be delivered via the auditory

channel, if visual is not an option.

2.3 Usability Aspects

E-learning devices can add to the learning task the

dimension of interactivity while the learner can still

proceed studying at their own speed. In order to truly

beneﬁt from an e-learning program, it must be consid-

ered usable, that is, “useful, efﬁcient, effective, learn-

able, satisfying, and accessible” (Rubin and Chisnell,

2008, p. 4ff.). The most important aspect is probably

usefulness since no one will engage with a program

that does not help them achieve a relevant goal. How-

ever, if any of the other aspects is not in place, the user

experience is not likely to be a good one. The pro-

gram must be both efﬁcient and effective. That is, it

must keep its promise and help the user with their task

but must do so in a reasonable amount of time. All

the while, the program should be learnable and satis-

fying, i.e. focus on key elements in a simple and en-

gaging way. The aspect of accessibility is especially

important when designing software for users who are

visually impaired. They have three access modes to

the computer, namely, (1) screen magniﬁer, (2) braille

display, and (3) screen reader. A screen magniﬁer

can only be used by those who have some vision left,

a braille display only by those who are braille liter-

ate, and a screen reader can be used by all visually

impaired users. Many who know braille choose to

use braille and text-to-speech technology together,i.e.

they navigate with a screen reader and read words

words with a braille display. Thus, screen content is

available to the visually impaired with the help of as-

sistive technology. However, as Shinora (2009) notes

“[s]imply replacing one interaction mode, such as the

display of text on a screen with a functionally equiv-

alent mode as in speaking text aloud, is not necessar-

ily equivalent from the point of view of user experi-

ence.” (Shinohara, 2009, p. 66). Hence, navigation

and contents of a CAVL application for the visually

impaired should ideally be designed for the intended

output mode. “[E]xcept for a very limited range of

products, ‘design for all’ is a very difﬁcult, if not of-

ten impossible task” (Newell and Gregor, 2000) as

cited in (Shinohara, 2009, p. 61). Since the screen

reader is experienced as usable by the majority of vi-

sually impaired people, it can then be concluded that

e-learning navigation and content should be adapted

primarily for auditory output.

2.4 Problem Formulation

For CAVL programs to be usable for visually im-

paired users, they should be fully accessible with a

screen reader and still focus on the orthographic form

of words. It is didactly plausible to deliver ortho-

graphic feedback via the auditory channel. To ﬁnd

out which feedback works best and which additional

features render a CAVL application usable for the vi-

sually impaired, target users must be involved in the

development process. This is why a user-centered-

design approach has been adopted in the development

of AVoS.

3 METHODOLOGY

In order to address the needs of the visually impaired

target group, the primary output mode of CAVL pro-

grams should be auditory but still be able to teach

orthography. It is important to involve the users in

the design process to make sure the solution is for

them. How can an orthographic error be corrected

via the auditory channel? Is this as efﬁcient as the vi-

sual highlighting of errors is for sighted users? More

importantly, is this option usable? Who would bene-

ﬁt from an auditory vocabulary and spelling trainer

and how? Answers to these questions can best be

found in collaboration with the target users. There are

two strands of research that require user involvement.

First, the target user must be adequately described.

Second, the program must be evaluated in terms of

its usability aspects. We have adapted a user-centered

design approach following the suggestions by Rubin

at al. (Rubin and Chisnell, 2008, p. 12ff.). One cy-

cle in the design process describes the following four

steps:

Step 1: deﬁne goal / concept.

Step 2: implement the idea.

Step 3: conduct user test.

Step 4: evaluate the results.

In the development of AVoS, the cycle has been

completed one and a half times already. The remain-

der of this paper reviews the ﬁndings from the ﬁrst

cycle and describes the transition between steps 1 and

2 of the second cycle.

CSEDU 2011 - 3rd International Conference on Computer Supported Education

464

4 USER-CENTERED DESIGN IN

THE DEVELOPMENT OF AVoS

The goal is to design a usable CAVL software for the

visually impaired. This means that the primary output

mode should be auditory. In terms of content, there

should be a good balance between addressing vocab-

ulary items with regard to their meaning and their or-

thographic form.

4.1 First Cycle (Completed)

The key objective of the ﬁrst cycle in the develop-

ment of AVoS was to evaluate the basic concept of an

auditory CAVL application for the visually impaired.

Details of this study can be found in (Stein, 2010).

The evaluation of an AVoS prototype took place

under controlled testing conditions at the Carl-Strehl

Gymnasium in Marburg, Germany. 15 visually im-

paired pupils from levels 6 to 9 participated in the

study, aged 12 to 16. The evaluation was divided

into three parts. (1) The subjects were asked to com-

plete a questionnaire to enquire about their vocabu-

lary study and computer usage habits. (2) Test per-

sons worked with the AVoS prototype and completed

a pre-test and a post-test to measure their progress.

This served to measure both spelling and vocabulary

performance objectively. To this end, a randomised

and controlled [2 x 2] factorial between-groupsdesign

was adopted. The subjects were assigned randomly to

one of two orthographic feedback conditions: simple

auditory feedback (S-AF) and prosodically enhanced

auditory feedback (PE-AF). In the S-AF condition,

words were spelled aloud in the case of a spelling er-

ror. In the PE-AF condition, words were also spelled

aloud in the case of a spelling error but the errors were

located by prosodically enhancing their position. (3)

The students ﬁlled in a questionnaire to report their

user experience.

The following gives an overview of our ﬁndings

from the evaluation upon the completion of the ﬁrst

cycle in the AVoS development.

(1) What are Typical Vocabulary Study and Com-

puter Usage Habits among Visually Impaired Lan-

guage Learners? The test subjects of this study

relied extensively on braille reading and list learn-

ing when studying foreign vocabulary and orthogra-

phy. They did not beneﬁt from index cards in braille

script or from the auditory output of the PC. Further,

subjects singled out spelling as their biggest handi-

cap in the L2 classroom. In terms of mental ortho-

graphic representation, they indicated that they pic-

ture spelling both haptic and auditorily. When us-

ing the computer, the test subjects relied on both the

screen reader and the braille display but prefered the

screen reader. Spelling errors in computer documents

were commonly corrected using the spelling option of

the screen reader or the brailler display, again with a

preference for the screen reader.

(2) Do Test Subjects Improve their Vocabulary

and Spelling Performance when They Use AVoS?

Does the Prosodically Enhanced Feedback Have

any Effect on Performance? Working with AVoS

improvedboth vocabularyperformance(Pillai’s trace:

F(1;9)=129.452, p<0.001 (two-sided)) and spelling

performance(Pillai’s trace: F(1;9)=129.898, p<0.001

(two-sided)) signiﬁcantly between the pre-test and

the post-test. The prosodically enhanced audi-

tory feedback (PE-AF) contributed to a signiﬁcantly

larger learning gain for spelling performance than

the simple auditory feedback (S-AF) (Pillai’s trace:

F(1;9)=5.030, p=0.026 (one-sided)). For vocabulary

performance no difference between the two condi-

tions was found. Subjects who received the prosod-

ically enhanced feedback were able to correct their

mistakes faster. However, this result was not signiﬁ-

cant.

(3) Which Features of AVoS Work Well and which

Could be Improved? The test subjects classiﬁed

the design of the feedback generally as usable, irrel-

evant of which testing condition they were assigned

to. 14 out 15 test subjects indicated that they would

like to work with such a tool to study vocabulary and

spelling. They pointed out that they found it helpful

that the entire word was spelled after a mistake, that

words were repeated until they were known, that they

had access to several control options, and that they

could only move on to the next word once the correct

word had been entered. In terms of the general sys-

tem design, most subjects commented positively on

the diversity of the feedback utterances, while some

found this feature somewhat annoying. The missing

braille line was not a problem, it was rather seen as

a beneﬁt by some subjects. The speech synthesis that

was adopted received largely negative comments and

should ideally be replaced by better voices.

4.2 Second Cycle (Partially Complete)

The key objective of the second cycle in the devel-

opment of AVoS is to improve the protoype and al-

low for more sophisticated user interactions. Again,

before doing any implementation work, it is impor-

tant to re-assess the needs of the target group. From

the evaluation in cycle 1, there are indications as to

DESIGNING WITH AND FOR THE VISUALLY IMPAIRED: VOCABULARY, SPELLING AND THE SCREEN

READER

465

which improvements of AVoS are desirable. How-

ever, the evaluation has been conducted among only

15 school children. This explains the need to evalu-

ate a more global demand of an auditory vocabulary

and spelling trainer. To this end, an online survey has

been conducted, using the barrier-free tool soscisur-

vey.com. The survey has been completed by 88 vi-

sually impaired adults out from which 77 sets of data

could be evaluated. The youngest test participant was

10 years old, the oldest was 74 years old and the mean

age was 38.4 (SD=13.794). The majority of test sub-

jects had achieved a university degree (29.5 %) or

completed high school (16.7 %). Also, most partic-

ipants speciﬁed their braille literacy as “very good”

(67.9 %). Test subjects were asked to answer a total

of 18 questions concerning their vocabulary learning

and computer usage habits, and their usage of vocab-

ulary learning software. Further, in an open-ended

question, the subjects could indicate which features

were important to them in a CAVL application.

(1) What are Typical Vocabulary Study and Com-

puter Usage Habits among Visually Impaired Lan-

guage Learners? The results from the online sur-

vey show that language learners with visual im-

pairments struggle signiﬁcantly more with acquiring

spelling of an L2 vocabulary item than with acquir-

ing its meaning. Consultation of the chi-square dis-

tribution χ

(df=1)=12.737 shows that the probability

of observing this difference is signiﬁcant on a level

of p<0.01. In terms of ﬁnding spelling mistakes in

a text on the computer screen, more test participants

indicated that they ﬁnd the mistake from the mispro-

nounciation of the text-to-speech synthesis rather than

ﬁnding it with the braille display. On a scale from

1 (never) to 7 (always) of how often they apply ei-

ther method, the mean for the screen reader was 4.59

(SD=1.814) and for the braille display it was 4.19

(SD=2.134). Tested against the middle value 4 (some-

times), the deviation was signiﬁcant in the case of

the screen reader (t(67)=2.674, p<0.01 (two-sided)).

Further, there is a statistically signiﬁcant correlation

between how well visually impaired people know the

braille script and how much they like to engage in for-

eign language study F(1;72) = 4.052, p<0.05 (two-

sided).

(2) Which Features are Desirable in an Auditory

Vocabulary and Spelling Trainer among Adult

Learners? 68 test subjects answered this question

and mentioned the following features as making a

CAVL application usable for them: pronounciation

help 48.5%, orthographic feedback 30.9%, screen-

reader friendly 25%, context of the vocabulary item

20.6%, ﬂash card method 23.5%, simplicity of the

program 19.1%, braille line access 17.6%. Further,

some test participants noted grammar help, display of

progress, online dictionary, free of charge, and rich

contrast for the display.

(3) How can the Findings from the User Survey be

Implemented into the AVoS Prototype? Based on

the results from cycle 1 and the results from the on-

line survey, the following additional features should

be included in the next prototype of AVoS:

Pronounciation Help. Provide formant text-to-

speech synthesis in the according language to al-

low a more natural pronounciation.

Intermediate Pronounciation. Include a func-

tion to listen to the word ‘so far’. Visually im-

paired people can easily pick out spelling er-

rors from the misprounounciation of their screen

reader. This feature could help them to verify their

input easily before submitting their answer.

Braille Line Access. Usability for screen reader

and braille display. While the screen reader is of-

ten prefered, good accessibility via braille line is

also needed.

Context. Present vocabulary in the context of a

sample sentence. This could be achieved via ex-

ternal links to online dictionaries.

4.3 Next Steps

The results of the online survey give some great in-

sights about the vocabulary learning and computer us-

age habits of visually impaired adults. Moreover, it

provides some valuable information about what fea-

tures are needed within a CAVL application in order

to render it usable to the target group. This shows

how important the interaction between the developers

and the end users is. It is simply not enough to have

theoretical knowledge about the target group.

Following the survey among adult language learn-

ers with visual impairments, a survey among visually

impaired children and youth will be conducted. This

should identify whether their needs in terms of vo-

cabulary learning and computer usage differ. Once

the new features are implemented in the next AVoS

prototype, it will again be evaluated with visually im-

paired users. In order to reach a larger group of test

subjects, the evaluation would ideally be carried out

online. Moreover, it would beneﬁcial to conduct a

longitudinal study and compare the effect of AVoS to

that of traditional CAVL software.

CSEDU 2011 - 3rd International Conference on Computer Supported Education

466

5 CONCLUSIONS

It has been discussed that for visually impaired lan-

guage learners, it is both usable and effective to

learn vocabulary and spelling via the auditory chan-

nel within a computer-assisted vocabulary learning

(CAVL) application. Auditory is the prefered access

modality to the computer screen for manyvisually im-

paired people. Unfortunately, this makes spellings of

words invisible. Yet orthography is a major challenge

for many visually impaired people in the L2 class-

room. This explains the need for a CAVL tool which

is designed speciﬁcally for auditory output and can

still provide adequate orthographic feedback. In or-

der to design a program that truly reﬂects the needs of

the target users, they must be involved in the devel-

opment. A prototype of an auditory vocabulary and

spelling trainer (AVoS) has been evaluated with 15 vi-

sually impaired pupils yielding promising results in

terms of the usability of the program. Further, an on-

line survey amongst 88 visually impaired adults pro-

vided insights about the vocabulary study and com-

puter usage habits of the target group. It has been

found that many people ﬁnd spelling errors in texts

on the computer screen due to mispronounciations of

the screen reader. Finding such as these can be used

in the further development of AVoS. The overall goal

is to provide a CAVL software for visually impaired

users that allows them the same beneﬁts sighted users

receive from traditional software. This e-inclusion

technology could potentially bridge the gap the two

user groups in the realm of computer assisted vocab-

ulary and spelling learning in the L2 classroom.

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