An international research group, led by researchers from the University of Turku and Turku University Hospital in Finland, has successfully pinpointed the likely source of stuttering in the brain. Stuttering, a speech rhythm disorder, is defined by involuntary repetitions, prolongations, or pauses in speech that disrupt typical speech production. It affects approximately 5-10% of young children, and an estimated 1% continue to stutter into adulthood. Severe stuttering can have a significant impact on daily functioning and quality of life.
Stuttering can have a significant negative impact on the life of the person experiencing it.
“Stuttering was previously thought to be a mental health issue. However, research has shown that it is actually a brain disorder related to speech production regulation,” explained Professor Juho Joutsa from the University of Turku.
Stuttering can also be acquired due to certain neurological conditions like Parkinson’s disease or a stroke. However, the neurological mechanisms of stuttering are not fully understood, and its origin in the brain is still uncertain. The results from brain imaging studies only provide partial information.It is difficult to determine which changes are the main cause of stuttering and which are just associated phenomena.
A new study found that regardless of the cause, stuttering is localized in the same brain network. The research, conducted by a team of scientists from Finland, New Zealand, the United States, and Canada, focused on individuals who had experienced a stroke, some of whom developed a stutter immediately after. Despite the strokes occurring in different areas of the brain, they all localized to the same brain network.the strokes that did not cause stuttering.
Furthermore, the scientists utilized magnetic resonance imaging (MRI) to examine the brains of 20 people who had developmental stuttering as well as those who had suffered a stroke. They found that the individuals with developmental stuttering exhibited structural changes in the brain network nodes that were previously associated with causal stroke lesions. The more severe the stuttering, the greater the changes in these brain network nodes. This discovery suggests that stuttering may be linked to a common brain network, regardless of whether it is caused by developmental or neurological factors.
The researchers identified the key nodes of the network as part of their study.Within the brain, the putamen, amygdala, and claustrum are deep-seated structures. The study’s findings shed light on well-known aspects of stuttering, such as the challenges in speech production and the variation in severity of stuttering based on emotional states. The putamen and amygdala play crucial roles in regulating motor function and emotions, respectively. Additionally, the claustrum serves as a hub for multiple brain networks and facilitates the exchange of information between them. This research offers a distinct understanding of the neurological foundation of stuttering.New research on the brain could lead to improved medical treatments in the future, including targeted brain stimulation for conditions like stuttering. This could be a game-changer for people with speech disorders. The study, published in the journal Brain, identified specific brain networks related to stuttering and the potential for treating it with brain stimulation. The researchers are hopeful that this could lead to more effective treatment options for stuttering.
