Impaired reading and writing ability due to aphasia caused by stroke or by low-grade glioma

Research project
Active research
Project owner
Institute of Neuroscience and Physiology at the Sahlgrenska Academy

Swedish Research Council Swedish Stroke Association Swedish Aphasia Association

Short description

Writing is a complex and cognitively demanding activity, which is why brain damage often affects writing ability. The research project aims to add knowledge about how aphasia – language impairment due to acquired brain damage caused by e.g. stroke or tumours – affects written language. The focus is on writing skill, but reading skill is also studied. Findings so far include that spelling tests say little about the ability to produce coherent texts, that the type of writing task influences results, that careful analysis of the writing process can yield key information about writing ability, that a book club can be very rewarding even for those who find it hard to read, and that those undergoing surgery for low-grade glioma (a type of tumour) write more slowly and need longer to find the right words when writing than before their surgery.


Aphasia is a multimodal language disorder affecting spoken and written language which is the result of acquired brain damage. The most common underlying cause is stroke. Those who have aphasia know exactly what they want to say but have difficulty finding the right words, may have difficulty putting the words together into grammatically correct sentences and may also have difficulty understanding what someone else is saying. The ability to write and read is usually affected as well. Another cause of aphasia including impairment to the ability to read and write is surgery for low-grade glioma, a type of brain tumour. This typically has a less pronounced effect. Research and clinical work have traditionally focused on rehabilitation strategies aiming to improve spoken language. However, given the increasing importance of written language in present-day society, there is need for more detailed knowledge about how writing and reading ability is affected and how it can be improved. The research project is divided into four parts, of which two focus on aphasia and writing ability, one focuses on reading ability and one focuses on writing in people with low-grade glioma. The research is based on careful analyses of the participants’ writing and reading as well as on the participants’ own reported experiences. All data have been collected and the analytical work is ongoing.


The overall aim is for the project to help improve the care of people with aphasia or other cognitive impairments due to brain damage. A more specific aim is to investigate what cognitive processes interact when a person is writing, how those processes are affected by aphasia and how the ability to write and read can be improved.

Research questions

• What cognitive processes interact when a person with aphasia is writing a text?

• What effect does training to use spell-checking software have on the writing ability of persons with aphasia?

• What were the experiences of the people with aphasia who participated in a book club?

• How is writing affected in people who undergo surgery for low-grade glioma?


The first part of the project is a group study where 16 people with aphasia were given the task of writing stories on a computer and performing a number of linguistic and cognitive tests on three different occasions at one-year intervals. Their stories were compared with corresponding stories written by a reference group of people without known neurological disease. The second part is an intervention study with a single-case experimental design (SCED) using multiple baselines. Seven participants with aphasia were given training in how to use spell-checking software over an eight-week period. Writing data were collected and analysed using keyboard logging, which records all keyboard and mouse actions performed by the writer, making it possible to analyse edits and pauses. The third part is a pilot project where four people with aphasia attended a book club for ten weeks. They were then interviewed individually about their experiences, and conversations at their group meetings were analysed. In the fourth and final part of the project, 20 patients with low-grade glioma were asked to write texts using keyboard-logging software before and after undergoing surgery for their tumours.


The results of the first part of the project showed that a spelling test does not say much about how a person writes a coherent text. Further, the people with aphasia made many edits in their texts, which greatly affected their productivity. They wrote stories with a less varied vocabulary than the reference group, often misspelling long and unusual words. The most common type of misspelling made by people with aphasia was the omission of letters. There are also misspellings that are specific to people with aphasia. The analysis of the edits made while the participants were writing their stories showed that what is decisive is not the amount of editing but the strategies used for editing. Long and unusual words are more difficult to edit, and there was found to be a relationship between knowledge of how the different letters sound and the ability to make correct changes. Further, results were partly dependent on story genre. The results from the intervention study (second part of the project) showed that the participants scored higher on a dictation test after receiving training (analysis of other results is ongoing). The findings from the book-club study (third part) showed that the participants saw reading together in groups and then discussing what they had read as a positive experience but considered that the structure of this activity had to be flexible and based on each individual’s needs. Conversational topics dealt with at meetings often took the book and its characters as their starting point but then led on to other interesting discussions. In the fourth part of the project, writing was found to be affected by surgery for low-grade glioma: after the operation, participants wrote more slowly and it took longer for them to find words as they were writing.


Traditionally, writing ability in aphasia has been examined using dictation tests with a focus on the spelling of single words. This provides some information about how a person with aphasia writes, but the present results clearly show how important it is to take a much broader perspective, examining text writing in different genres but above all also analysing the writing process and not just the final text. The work of writing a text includes putting ideas into words which are then to be committed to paper (or screen), but also planning the content, reading the text, changing its wording, adjusting sentence structure and correcting spelling errors. Writers typically do all of these things as an integral and necessary part of the writing process, but if too much energy has to be devoted to spelling and the editing of spelling – which was the case for the participants in the present project, especially those with aphasia after stroke – other aspects or (sub-)processes (including productivity) are negatively affected. It was found that writing was less affected in the people who underwent surgery for low-grade glioma than in those who had post-stroke aphasia. The changes observed post-surgery related mainly to temporal aspects such as writing speed and pausing. The experiences from the book club showed that the participants experienced the meetings as very rewarding and that the key aspect was the shared reading experience rather than individual reading ability.



Åsa Wengelin

Charlotte Johansson-Malmeling

Lena Hartelius

Katja Laakso

Malin Antonsson
Francesca Longoni