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Web Posted on: December 17, 1998


COMPUTER ADAPTIVE REMEDIAL-TREATMENT OF LOW-VISION CHILDREN SPELLING DIFFICULTIES - "PUPIL" SYSTEM

D. Mioduser
O. Lahav
Tel Aviv University
School of Education
Israel
E-mail: lahavo@post.tau.ac.il

Introduction

The acquisition process of correct spelling by low-vision children is affected by factors which can be referred to as cognitive consequences of their physical impairment. Ehri (1980) suggests that a word stored in the long-term memory holds a number of identities, i.e., acoustic, visual, syntactic, semantic, contextual, kinesthetic. Since visual information plays a central role in the consolidation of linguistic identity, the lessened performance of the visual channel affects negatively the construction process of the syntactical properties of the stored word and consequently, the stored word's value as referential model for correct spelling (Ehri, 1980; Wohl, 1984; Perfetti, 1991). Low-vision children learn to read complete configurational units (e.g. words), and whatever the visual channel gets in incomplete or unclear form, the mind completes by using additional external and internal information.

The work reported is an attempt to support low-vision children in coping with spelling mistakes, by means of a diagnostic and remedial adaptive computer tool. Our work is guided by three main assumptions: (a) Low-vision children's should be compensated by alternative information-input channels; (b) The support to be given should build upon the children's spontaneously activated "completion strategy"; (c) The support should be highly individualized. Based on these assumptions we developed "Pupil", a computer adaptive remedial system.

The "Pupil" System

The "Pupil" system diagnoses misspelling by categories of mistakes and by spelling rules. One main component of the system is the diagnostic module, and the other is the remedial module. The unit of work in "Pupil" is the task, a set of 15 exercises composed by the system on the basis of diagnostic data. A typical exercise presents a sentence in which the target word is missing, and it has to be typed in by the student.

The catalog of words and sentences from which the exercises are composed was the result of a previous study which mapped the low-vision students' most frequent spelling mistakes in the Hebrew language (Lahav, 1997). The resulting, catalog of 523 words was indexed according to two criteria: the syntactic rule and degree of difficulty of each word.

At the beginning of each session student have the possibility to adjust basic layout features (e.g., font size, font and background color, sound) to their needs and preferences.

The first session with "Pupil" is a diagnostic session, as a result of which the subject's spelling difficulties are modeled and located within a space of grammatical and intuitive rules (Lahav, 1997). Following come the treatment sessions, during which the student model is continuously updated. This model guides the generation of the subsequent tasks by the system. A detailed report is generated for the teacher, who can review all information in varied configurations. Different support tools are offered to the student, e.g., perceptual support , conceptual support, or syntactic information. The content of the tools at any given time corresponds to the actual exercise (or target word), and can be activated by the student at her or his own pace.

Figure 1

Figure 1 - Example of sreen layout for a spelling exercise, support tools (e.g., spelling, sound, image, rule)

A Case Study

A case study focusing on one student's remedial work with the system is described in this paper.

Subject

The subject, H., is an eighth grader. For reading and writing purposes she requires Closed Circuit TV in class and at home. Her work in class is based on auditory information or the use of the enlargement CCTV system. She does word processing by blind typing.

Method

The case study consisted of three stages:

Pre-assessment diagnostic session: At the beginning of the diagnostic session the subject received a short explanation about the system's features and operation and about its diagnostic tasks. The diagnostic session lasted about two hours.

Treatment sessions: Based on the diagnostic results a treatment plan was generated by the computer system focusing on the spelling rules on which the student showed poor performance. The treatment consisted of 13 sessions (31 tasks, total practice on 394 words).

Post-assessment diagnostic session: Similar in structure and number of tasks to the pre-assessment session. At the end of this session an interview was conducted.

Two data-collection instruments were used in this study. The first was a log mechanism built-in in the computer system which stored all subject/system interactions. This material was used for updating the student model. The second data collection procedure was non-structured and non-interventional observation. In the pre- and post-assessment sessions data were collected for the following variables:

  1. correctness of the answer;
  2. response time,
  3. reading out loud of the sentence by the subject before typing the target word;
  4. request for repeated dictation of the exercise by the system.

During the treatment stage data were collected regarding the following seven variables:

  1. number of spelling mistakes;
  2. kinds of spelling mistakes;
  3. consistency of mistakes;
  4. stabilization point of correct spelling;
  5. response time in solving an exercise;
  6. changes in writing tactics;
  7. changes in use of the visual and auditory channels.

Results

The results will be presented a selected samples:

  • spelling performance - The results show a significant increase in grade (correct /incorrect) (18%) and in number of times the subject read the sentence before answering (66%). A significant decrease was registered in mean response-time (23 seconds) and in number of repeated dictations of the exercise the subject requested (25%).
  • correct spelling - Two variables supply relevant information for this question: response time and correctness of the answer. The results show that for which H's spelling improved between the pre- and post-assessment, response time decreased. For correctly spelled by H. in the post-assessment response time decreased.These data can be considered in line with the assumption that improvement in spelling performance together with decrease in response time implied an automation trend in H's spelling skills.
  • supporting tools - The data suggest a two-stage pattern. First there is a correspondence between misspelling and recurrent use of a support tool. Following the use of a tool after misspelling, the word is then correctly spelled.

Discussion

Saimon and Saimon (1973, 1979) suggested three operational spelling modes, in correspondence with the amount and quality of knowledge a subject owns about a target word: (a) automatic retrieval, (b) spell-and-check cycle, and (c) phonetic writing (based on sound mimicry). The last mode has the highest potential for misspelling, particularly for letters with phonemical similarity. It is also the most frequently used by low-vision children, who do not rely on reference information from the visual channel but on incomplete (and often incorrect) word models stored in memory. The detailed data obtained in this case study show a clear evolution path in the student's performance. From phonetic writing in the first sessions the student moved to process-writing, typing the word and checking it. Initially the student typed the word using her partial spelling knowledge, then she looked for help from the system's support tools, and finally evaluated the result according to correctness criteria stored in her memory. In the advanced stages of learning H. was able to automatically retrieve the spelling of the word.

Another central issue concerns the role of the support tools in the system. The tool most frequently used by H. was "spelling" (literal auditory spelling of the target word), which she considered the fastest help. This tool seemed to have a twofold effect. The first and most obvious was that of supplying immediate help in solving the task. But in addition it served H. to develop models of the words by relating auditory information to visual information about particular letters and letter configurations. As H's work advanced she started to replicate the system's spelling by herself before and during the actual typing of the target word, in the process of the cognitive assimilation of the word as automatically-retrievable unit.

H's use of alternative information channels deserves special attention. As could be expected, support relying on the auditory channel was of great use. But as the work proceeded the use of the visual channel increased. The student spent increasing time reading the sentence before typing the target word. At the same time the demand for auditory support (e.g., repeated uttering of the target word by the system) decreased.

A final remark should be made about our research agenda. We have already collected additional case-study information, as well as started a systematic study with a larger group of low-vision children.

Bibliography

Ehri,L.C. (1980). The Development of Orthographic Images.In U. Frith (Ed.), Cognitive Processes in spelling. London: Academic Press, (p. 311-338).

Lahav, O (1997). Computer Assisted Treatment for Spelling Difficulties Among Low-Vision Children. Unpublished M.A. Thesis, Tel-Aviv University, (Hebrew).

Mak, Z. (1993). Writing Path : Spelling Mistakes, Diagnostics and Remedial Treatment. Jerusalem: Z. Mac (Hebrew).

Perfetti, C. (1991). The Psychology, Pedagogy and Politics of Reading. Psychological Science, 2(2).

Saimon, D. P., & Saimon, H. A. (1973). Alternative uses of phonemic information in spelling. Review of Educational Research, 43(1), 115-137.

Saimon, D. P., & Saimon, H. A. (1976). A task analysis. Instructional Science,5, 277-302.

Wohl, A. (1984). Writing Skills - Psychological and Didactic Aspects. Psychology & Education Consulting. Tel-Aviv: Otzar Amore, 139-153 (Hebrew).