Research in to Stammering

Research on Attention and stammering in adults

Researcher Silviya Doneva has recently completed a year-long research project investigating the links between attention and stammering in adults, funded by the Trust and supervised by Dr Penny Cavenagh at University Campus Suffolk. This builds on earlier work undertaken at UCS which found that children who stammer may also experience difficulties with sustaining attention. Silviya has been testing the hypothesis that stammering interferes with control of processing information and thereby affects the performance of everyday tasks.

Silviya has found a difference in attention between people who stammer and people who are fluent speakers and that people who stammer have more difficulty in sustaining attention when undertaking tasks. Although her research suggests a link between the severity of a stammer and difficulties with attention, it is not clear which is cause and which is effect.

Screening school-aged children for stammering

Avin Mirawdeli, supervised by Professor Peter Howell of UCL, is nearing completion of her PhD at UCL, which is co-funded by the Dominic Barker Trust and UCL. Entitled “Screening school-aged children for fluency problems : an investigation in Suffolk Schools”, Avin has been working to develop a universally-applicable screening tool to identify children in Reception class who have speech difficulties. Her work has received positive reactions from the schools where she undertook her research. The work identifies children in schools who stutter (in Ipswich and London) and following identification, schools have also asked that in-school interventions be conducted for children who either: 1) stutter; or 2) show word-finding difficulty that can sometimes sound like stuttering. The latter affects children who do not speak English as their native language in schools. Four papers are at different points in the publications process. Further details can be found at

Building on Avin’s work, researchers at UCL, funded by the Trust, are developing an intervention for in-school use with children who stutter. This study first validated Avin’s procedure by applying the screen on 170 reception class children. The effectiveness of the newly-designed two-week working memory intervention was investigated, testing the hypothesis that working memory training would lead to short- and long-term improvements in speech fluency and non-word repetition (NWR) ability. As predicted, results showed immediate improvements and long-term retention in effects for both speech fluency and NWR ability. Schools now have a package that allows them to identify and perform a preliminary intervention for speech difficulties among reception class children.

Brain imaging research into stammering and speech mechanisms

Thanks to a very generous donation from the Mackie Foundation, the Trust is delighted to be co-financing a PhD with UCL which is investigating the Impact of Transcranial Direct Current Stimulation (tDCS) on Speech Fluency. Researcher Naheem Bashir, supervised by Professor Pete Howell, is investigating the effect of stimulating the brain with transcranial direct current stimulation (tDCS) in conjunction with the use of conventional treatment for stammering. He has so far shown that this combination does seem to work to improve speech in fluent speakers, so providing proof of the principle that tDCS can have a positive effect on speech mechanisms. There are several lines of research that Naheem is following. One study involves tDCS as an adjunct to conventional therapy. Another study currently being planned aims to assess if tDCS is more effective when delivered during or before an assessment. A further study will involve using a brain imaging system (NIRS) to look at assessing brain activity in real-time in social situations, as well as fluency enhancing situations, in people who stammer. Naheem hopes this will give an insight into the mechanisms of stuttering, as well as fluent speech production in people who stutter, and an insight into variations in speech fluency levels experienced by people who stutter in various different situations, for example high fluency when speaking alone as compared to low fluency when introducing oneself to a stranger. This could possibly provide new neural targets for treatment and have exciting implications for use in therapy.