Researchers at the Vrije Universiteit Brussel suspect there is a link between stuttering and the quality and quantity of sleep in children aged four to 13. Previous research has shown that sleep problems can cause drowsiness, fatigue attention disorders, anxiety and depression symptoms and, the VUB researchers believe, the intensity of stutters.
"Children often show ’unfluency’ in their speech around the age of two to five," says VUB sleep expert Professor Olivier Mairesse. "After that, around age seven, the problem resolves itself for about 75% of children. For some, it may persist into adulthood. We are mainly interested in the experience of parents of primary school children regarding sleep, wakefulness and stuttering behaviour. Through network analysis, an innovative method that allows us to uncover complex relationships between symptoms, we are looking at what other symptoms occur with the issue and how they may affect each other."
The idea of linking sleep and stuttering comes partly from earlier experiments, in which adolescents who stutter were given hypnotic medication to see if the intensity could be reduced. Today, stuttering is also linked to ADHD. Again, there is a link with sleep behaviour: lack of sleep can cause ADHD-like symptoms, possibly including speech impediments. "The intention is to eventually identify therapeutic targets through network analysis, as we expect that sometimes a limited number of symptoms can cause or explain a whole range of other symptoms," Mairesse says.
The big challenge for the study is to find enough subjects. "Analysis like this requires as many as hundreds or thousands of participants," says Mairesse. "We have already contacted nearly 80 speech therapists asking if they have potential patients in their practice who could fit into our study. We want to include both stutterers and nonor ex-stutterers. So far, there are 436 participants, of which only 18 are Dutch-speaking and seven are French-speaking. There are also significantly more boys than girls in the study group, which is normal: there are more boys who stutter than girls."
Anyone who thinks they may be a suitable participant can contact Prof Mairesse or see.