A New Zealand researcher is challenging the notion that stuttering in children could be linked to personal anxiety.
Bianca Phaal, a masters student in the Department of Communication Disorders at the University of Canterbury, has just completed a study looking at the anxiety levels of a group of three and four-year-olds who were at the onset of stuttering and compared this with a control group of non-stuttering children.
Working with biochemist Dr John Lewis (Steroid and Immunobiochemistry Laboratory, Canterbury District Health Board), Bianca found no higher anxiety levels in children who stutter compared to non-stuttering children.
'There were no significant differences between the children who stutter and those who don't according to either of the measures of anxiety or the communication apprehension measure, neither was there any relationship between stuttering severity and anxiety or communication apprehension,' Bianca said.
'Results of this study suggested that generalised anxiety and communication apprehension are not associated with early childhood stuttering, therefore it is unlikely anxiety is the root cause of stuttering.
'However, should early childhood stuttering persist, negative experiences in speaking situations could lead to the development of communication apprehension and perhaps generalised anxiety. Early intervention for stuttering may thus be crucial in preventing this development.'
She had examined anxiety by collecting saliva samples from each child and measured the steroid levels of a substance called 'cortisol.'
Cortisol is a hormone released during periods of heightened anxiety, and can be measured in saliva by chewing on a dental roll. She also conducted communication apprehension tests with the children and surveyed their parents, asking them to rate their children's anxiety levels in different situations.
Professor Mike Robb (Communication Disorders) said the study's findings were important in better understanding the condition that affeceds about 1 per cent of New Zealanders.
'There is a long history of research in stuttering and its relationship to personal anxiety, with some theorists believing that anxiety 'causes' stuttering or that anxiety is an 'outcome' of stuttering. In any event, people feel as though anxiety is a core feature of stuttering.
'In this particular case, accepting the null hypothesis has important theoretical and clinical implications concerning the aetiology of stuttering. To my knowledge, this study is the first of its kind to quantitatively examine the role of anxiety in children who are at the cusp of developing this particular communication disorder.
'Bianca has also demonstrated how biochemistry can serve a role in research examining communication disorders,' Professor Robb said.