Matematiska färdigheter hos elever med lässvårigheter i årskurs 4

Sammanfattning: Reading difficulties is the most common learning difficulty in the western world and it is common that people with reading disabilities also exhibit arithmetic difficulties. Different theories about the cause of the relationship exists, one theory describes the importance of good phonological ability in reading as well as in arithmetic, while another theory describes the importance of a reliable number system and that only a subgroup of students with reading disabilities also have difficulties with arithmetic. The purpose of this study is to investigate how students with reading difficulties (RD), without any known mathematical difficulties, perform on mathematical tasks relative to a control group. The study was theoretically grounded on the Triple code model (Dehaene, 1992), which is a model for numerical information processing that describes how various numerical and arithmetic tasks are processed through three distinct representation systems in the brain, a verbal and a visual representation system and a quantity system. Reading skills, phonological skills, arithmetic skills and number processing skills were examined in 61 students through a variety of tests. After examination of reading ability, the participants were split into two groups, students with RD and a control group. Statistical comparisons were calculated by one-way analysis of variance between the two groups on each task, and for some tasks one-way analysis of covariance were used. The results provided partial support for the present hypotheses. The main findings showed that students with RD have difficulties within the verbal and visual representation system but exhibit an intact quantity system. Within the verbal representation system, students with RD performed significantly worse in retrieval of arithmetic facts (addition, subtraction and multiplication), they retrieved fewer established answers from long-term memory on all of the three arithmetic operations compared to the control group. The students with RD also made more errors regarding subtraction and multiplication and within the visual representation system they had significantly fewer answers that were correct on written arithmetic calculation and was significantly slower in symbolic number comparison, compared with the control group. It is discussed whether a connection difficulty, namely difficulties in linking a particular symbol with a semantic content, is the cause of the exhibited arithmetic difficulties in students with RD.