Clinical evidence for the compensatory role of the right frontal lobe and a novel neural substrate in developmental stuttering: A single case study

The neural substrates of stuttering have been a topic of extensive debate in the field of both neuroscience and communication disorders. Although a consensus on this issue is yet to emerge, the recent neuroimaging studies have shown consistent neural over-activations in the right hemisphere suggestive of its possible compensatory role in stuttering. In this context, we report on a 51-year-old, right-handed male subject with a history of resolved developmental stuttering who presented with sudden onset stutter speech and left hemiparesis following an episode of right frontal stroke. The speech and language evaluation revealed apparently dysfluent speech. Unlike the people with neurogenic stuttering, our subject revealed clinical features suggestive of developmental stuttering. Combining our observations with the evidences from the previous neuroimaging studies of developmental stuttering as well as clinical studies of both neurogenic and (post-stroke) reappeared stuttering, we support the hypothesis on the compensatory role of the right frontal lobe in developmental stuttering. In addition to this, we extend the currently known neural substrates of stuttering to a novel area - the right frontal parafalcine region.