Language function in the brain in adults with neurodevelopmental disabilities
What is the purpose of this study?
The right and left sides of the brain look similar, but have different functions. We can see this by measuring blood flow to the brain when people do language activities, such as naming pictures or generating words. In most people, the left side has more blood flow than the right during language activities, but this can vary. Some people have more blood flow to the right side for some language activities.
We are investigating whether people with neurodevelopmental conditions affecting language, reading and communication are more likely to use different sides of the brain for different aspects of language processing. We will test this idea by comparing student volunteers who have been diagnosed with dyslexia, autism spectrum disorder, or related conditions, with a ‘neurotypical’ group who do not have any diagnosis.
Who is this study for?
We are looking for student volunteers aged 18-30 years, both with a recognized neurodevelopmental condition, such as dyslexia or autism spectrum disorder, and volunteers who are not affected by such conditions. All participants should be native speakers of English, and should not have significant hearing loss, history of neurological disease, head injury or epilepsy.
What will happen if I take part?
If you decided to take part in the study, you would be invited to come to the Department of Experimental Psychology on two separate occasions, each lasting around 2 hours. The interval between sessions would be between 1 day (on consecutive days) and 3 months apart, depending on your availability.
In the first session, we would use different tests to assess the pattern of strengths and weaknesses in your language and literacy skills, and ask you to complete a self-assessment questionnaire to rate your communication skills. For some of the assessments, your speech would be audio recorded, to help with scoring.
We would then invite you back for a second session, where you would be asked to do some language tasks while blood flow in the brain is measured using a procedure called functional Transcranial Doppler Ultrasound. You can see a demonstration of this simple procedure in the video above.
This procedure for measuring blood flow in the brain is harmless and painless and carries no significant risk to participants. We first place a headset on the person’s head and adjust it to give a snug fit. A small amount of gel is placed just in front of each ear, and an ultrasound probe is held in place over this. Positioning of the probes to find the best signal from the arteries can take 10-15 minutes. The gel used to make the electrical contact is water based and can be wiped off easily with tissues or wet wipes.
Once the set-up is completed, you would be given two to three computer-based tasks that involve generating words, reading, or judging the meanings of sentences. Each task lasts around 20 minutes, followed by a 5 minute break. We would then remove the headset and give you a longer break. Lastly, you would be asked to do two other tasks, each lasting about 10 minutes: one involves reading words which are flashed on a screen, and the other involves repeating words that you hear through headphones.
We would ask you to let the researcher know if at any time you become uncomfortable. In that case, we would stop the study, without this having any negative consequences for you.
In around one in twenty people, it is not possible to get a good signal from the arteries because the bone in this region of the skull is thick. If this occurred, you would be paid for your participation in this session but not asked to continue.
What are the possible disadvantages and benefits of taking part?
There are no known or anticipated risks involved in taking part. There are no direct benefits to volunteers, but you would be helping advance scientific knowledge of how the brain works. If you come into the University, we will reimburse your travel expenses.
What will happen at the end of the study?
Once we have seen all the participants and gathered the information we will write about the results in the OSCCI newsletter, which is circulated among schools and families who have shown an interest in our projects. We will not report on the results of individuals. All data will be kept confidentially and anonymously. We will write our findings up for a scientific journal and present the findings to other researchers at conferences.
Funding and approval of this research
This study is part of an ERC funded project called ‘Cerebral Asymmetry: New Directions in Correlates and Etiology’. The study has been given ethical approval by the Central University Research Ethics Committee (MS-IDREC-R40410/RE001).
What to do next
If you would like to take part in this project, please fill in the response form here and we’ll get in touch with you. Also, if you have a question, please feel free to email firstname.lastname@example.org.