Why A Study On Yawning May Lead To A Tourette’s Syndrome Treatment
Most people know that yawning is contagious, but even the top neuroscientists have struggled to understand automatic mimicry, known as echophenomena. In a new study, scientists pinpointed the region of the brain responsible for mimicry, and they may have found a tool that could calm that area, which could result in more effective treatments for echophenomena conditions such as Tourette's syndrome and autism.
Echophenomena describes an automatic and subconscious imitation of someone else’s behavior, whether mimicking body language or their actual speech, The BBC reported. We all do this to a certain degree, whether we're mimicking a yawn or mirroring someone else’s stance. However, for some, this imitation can interfere with regular life. It’s here where the ability to prevent echophenomena would be useful. Trouble is, doctors haven't known how to do this.
Researchers at the University of Nottingham in the UK discovered the area of the brain responsible for these automatic acts of mimicry. It's known as the primary motor cortex, and unsurprisingly, it also plays a role in Tourette's syndrome. Better yet, the team may have discovered a technique with the power to calm this part of the brain, and potentially prevent it from prompting mimicry.
They used a tool known as an external transcranial magnetic stimulation (TMS) to increase the excitability in the motor cortex, which resulted in an increase in people’s susceptibility to mimicking yawns. They believe that decreasing the excitability may have the opposite effect.
"In Tourette's, if we could reduce the excitability we might reduce the tics, and that's what we are working on,” explained study researcher Georgina Jackson, The BBC reported.
According to the National Institute of Neurological Disorders and Stroke, Tourette Syndrome is a neurological disorder where individuals have repetitive involuntary movements and vocalizations known as tics. Although it's hard to accurately measure how many people have Tourette’s Syndrome, since the condition can vary in severity, the Centers for Disease Control and Prevention estimates that about one in every 360 children is diagnosed with the condition.
Symptoms include uncontrollable tics which are often sudden, brief, and repetitive movements. These can include eye blinking or facial grimacing, shrugging, or shoulder jerking. Individuals can also experience vocal tics, such as repetitive throat clearing, sniffing, or other noises. These tics can be random, but can also be triggered by excitement or anxiety.
Currently there is limited treatment for Tourette's syndrome. Sometimes neuroleptic drugs can be successful in suppressing tics or reducing tic severity, but overall the condition can only be managed, not cured, NINDs reported.
Next steps will include looking for possible ways to incorporate TMS into a treatment for certain patients to help them control imbalances in this brain circuit.
"If we can understand how alterations in cortical excitability give rise to neural disorders we can potentially reverse them,” Stephen Jackson, another study researcher, told The BBC.
Source: Brown BJ, Kim S, Saunders H, et al. A Neural Basis for Contagious Yawning. Current Biology . 2017