What is Tourette Syndrome?

Jul 29

Does your child experience unwanted and repetitive outbursts of sounds or movements? Does this cause significant stress for them in social situations? Your child may be struggling with Tourette’s syndrome.

How Common is Tourette Syndrome?

Tourette syndrome generally presents in early childhood, usually around the age of 6. The onset can be earlier or later, and tend to affect more boys than girls. The CDC has estimated that 1 out of 162 children have Tourette’s Syndrome (1).

What is a Tic?

A tic is a repetitive movement or unwanted vocalization that is difficult to control. Tics may be mild or severe, and can significantly interfere with communication and optimal quality of life. Simple motor tics include sudden, brief and repetitive movements that involve a small number of muscle groups. These are often behaviors such as eye blinking or facial grimacing. Simple vertical tics include repeated barking or throat clearing. Complex motor tics include coordinated patterns of movements involving several muscle groups, such as gesturing or repeatedly perform certain tasks or actions (8). Complex vocal tics include repeating one’s own words or phrases. Sometimes complex motor tics can involve self-harm behavior.

Tics may vary in frequency and severity over time and in varied circumstances. Anxiety, stress, illness, excitation and fatigue may make tics worse. They may become worse during puberty, and often improve into adulthood. There is typically an urge to perform the tic and, if suppressed, anxiety and discomfort produced by the attempt to hold it back. It can take a great deal of effort to suppress a tic.

What are Symptoms of Tourette Syndrome?

The inability to suppress tics are the primary feature of Tourette syndrome. A diagnosis of Tourette syndrome requires both a motor and vocal tic. To meet Tourette criteria, tics must occur several times per day, nearly every day, for over a year, in varying frequencies, originating before the age of 18.

The most common vocal tics include throat clearing, grunts, groans, clicking or other sounds. Motor tics are also common, involving spontaneous movements of the nose, mouth, head, neck, shoulder, or eyes. People living with Tourette syndrome typically repeat the same type of tic over and over. It is possible to have a tic without a Tourette diagnosis, as tics can be caused by medications, head injuries, and other syndromes. The media tend to portray Tourette syndrome as involving corprolalia, which is the involuntary and repetitive use of obscene language. While this can occur, it is rare, and the vast majority of people living with Tourette syndrome never demonstrate corprolalia (9).

How Does Tourette Syndrome Affect the Brain?

Tics are produced in response to an urge. The urge has been described as motivational anxiety. Imagine you are in a conversation with someone, are just about to make a critically important point, and right at the moment you are about to speak the other person cuts you off. This leaves you stuck in a motivational loop, with a degree of stress that will continue to cycle until you are finally able to make your point and diffuse the stress. This is the urge that people living with Tourette syndrome feel almost all the time. The urge develops because of dysfunction in dopamine pathways in the brain, including the frontal lobe and the basal ganglia.

Dopamine is a neurotransmitter involved in many varied functions. It is involved in the brain’s reward cascade. When we perform an action successfully, the brain releases dopamine to reinforce the successful action pattern.

Research demonstrates that Tourette syndrome is the result of a dysfunctional dopamine system (2,3). The theory assumes that total dopamine is low in the brains of those living with Tourette syndrome. This makes their dopamine receptors become HYPER sensitive, as they scramble to take any dopamine they can get. When a tic is expressed, the brain receives a dopamine hit from an abnormal source. This nevertheless reduces the urge, the brain feels rewarded, and over time it reinforces the tic.

Tic disorders and Tourette syndrome also appear to involve dysfunctional interneurons. These are neurons that are involved in modulation function between other neurons and pathways. They modulate the magnitude of pathway output and information processing. Interneurons appear to be both depleted and dysfunctional in Tourette syndrome (10).

Dopamine is a critical neurotransmitter in the basal ganglionic system. The basal ganglia network is one of the main modulating pathways in the brain. The frontal lobe and basal ganglia work together in the frontostriatal circuit, which functions as both the gas pedal and brake pedal for motor behavior and emotional regulation. The frontostriatal circuit appears to be dysfunctional in tic disorders and Tourette syndrome (11, 12).

How is Tourette Syndrome Usually Treated?

Tourette syndrome is typically treated with medications that modulate the dopamine system. These often include antipsychotics such as Haldol and Risperidone. In other cases, ADHD medications and antidepressants may be employed. It is common for Tourette syndrome to come hand in hand with other conditions such as ADHD and obsessive-compulsive disorder, and the presence of these other conditions can guide medication management. These may help control the symptoms, but do not directly address the dysfunction within the frontostriatal system. As with all medications, side effects are possible. These include weight gain, fatigue, restlessness, and social withdrawal. Behavioral therapies may also be helpful for children to learn more appropriate forms of expression to suppress their urge and break their patterns of tic reinforcement.

There is no gold standard of treatment for Tourette syndrome, and many children grow out of their tics in late adolescence. Unfortunately, by that time the stress and embarrassment a child has experienced can be life changing and crush their self-esteem.

How is the NeuroRescue Program Different?

The brain’s frontostriatal circuit is of critical importance in Tourette’s syndrome. This is a pathway involving the frontal lobe and the basal ganglia. Collectively they form one of the brain’s primary inhibitory systems. They work to suppress unwanted behavior and involuntary responses such as tics. Research shows that they become increasingly activated during the suppression of tics. As test subjects increased in age, greater activation was seen in the dorsolateral prefrontal cortex, a specific aspect of the frontal lobe that functions in response inhibition (4).

When our dopamine system is dysfunctional, our ability to inhibit unwanted responses is decreased. The ability to ignore the shiny object, the “squirrel” moment, or in this case, the urge, is reduced. The parts of the frontal lobes and basal ganglia involved in response inhibition are also directly involved in the production of specific classes of eye movements. We use advanced neurodiagnostic technologies to measure the function of these inhibitory systems. We can not only use these types of eye movements to measure the level of dysfunction in these pathways, but can also use them as a means to rehabilitate the system.

We have our patients perform Videonystagmography testing (also known as VNG), wherein we precisely measure a host of different eye movements with infrared tracking, and compare their results to those from normal subjects. One important eye movement that requires a great deal of inhibitory control is a saccade, which is a fast jump of the eyes from target to target. A prosaccade is when you quickly jump your eyes to a target. An anti-saccade involves jumping the eyes away from a presented target. Anti-saccades are harder to perform, as they require inhibiting the reflex that tries to make the eyes jump towards the newly presented target, and involve a conscious choice to move the eyes in the opposite direction.

Anti-saccades are produced directly from the dorsolateral prefrontal cortex, the important modulation center for response inhibition that becomes more active as the brain matures. We use anti-saccade exercises all the time in treating our Tourette syndrome patients, to activate the dorsolateral prefrontal cortex and enhance its ability to inhibit tics.

Jeter et al (5) studied prosaccades, anti-saccades, and saccades to remembered targets, which requires spatial memory in addition to eye movement accuracy. They found that Tourette syndrome patients had more frequent errors on their prosaccades, slower reaction time on anti-saccades, and had higher error rates on memory saccades.

Jung et al (6) studied saccades and anti-saccades with Tourette syndrome patients. They found that when provided an easy task of performing saccades to targets, Tourette patients had worse reaction times and velocity of movements compared with normal subjects. When saccades and anti-saccades were combined in the same test, the Tourette subjects performed BETTER than everyone else. They were worse at easier tasks than control subjects, but better at the harder tasks than control subjects. This implies that when someone living with Tourette syndrome has more challenging work to do, they perform better than they do with less stimulating, repetitive tasks. It also implies that by activating the dorsolateral prefrontal cortex, their ability to modulate is greatly enhanced.

Anti-saccade therapies are extremely effective, but are only one of myriad ways to activate the brain’s inhibitory networks. We use a wide variety of technologies and therapies to help build function in these pathways to help bring tics under control. These include rhythmic entrainment therapies to build modulation within the basal ganglia network. Motor timing has been shown to be impaired in children with Tourette syndrome and other associated basal ganglia disorders (13). We use a therapy system called the Interactive Metronome to rehabilitate these systems, which has been shown to be very effective (14).

Another secondary issue seen in people with Tourette syndrome is decreased balance and postural stability. Children with Tourette syndrome have been compared to healthy children under a variety of postural stability challenges. The children with Tourette syndrome showed greater deficits in maintaining stable upright posture, especially when undergoing challenges to their sensory systems (7). Deficits in posture increases a person’s fall risk, and therefore increases their risk of sustaining concussion.

Sometimes children or adults develop normally until they sustain a traumatic brain injury and their lives are forever changed. We know that Tourette syndrome is due in part to genes and how they interact with certain environmental factors. Unfortunately, traumatic brain injuries are known to alter gene expression, by turning on genes that code for the expression of tics.

There are a series of reflexes that we are all born with, called primitive reflexes. These help the brain develop, by creating specific motor patterns in response to sensory input. These reflexes are normal in infants, but should be all fully attenuated by the first birthday. There are direct associations with neurodevelopmental conditions and retained primitive reflexes. Children with Tourette syndrome often demonstrate a series of retained primitive reflexes. Exercises to attenuate primitive reflexes have been shown to be very helpful in a wide variety of neurodevelopmental disorders (15).

Non-invasive neurostimulation techniques have shown good promise in resolving Tourette syndrome and associated tic disorders. Transcutaneous direct current simulation (tDCS) is one such therapy, which involves a safe, gentle electrical current applied to the scalp. This helps improve function and integration between frontal and basal ganglia pathways, and has shown to be effective in reducing tics (16).

Another advanced technology shown to help people living with Tourette syndrome is transcranial magnetic stimulation (TMS). This involves an MRI-strength magnet with a focused beam of magnetic energy applied to the forehead. It stimulates the dorsolateral prefrontal cortex directly through the skull. As we have already seen, the DLPFC is a primary center involved in executive function and inhibitory control. TMS therapy can produce significant improvement in behavioral modulation, including the suppression of tics (17). We reserve tDCS and TMS therapy for people over the age of 18. Unfortunately, the effects of Tourette syndrome often persist into adulthood.

Every NeuroRescue Program is different, with your therapies chosen based on your diagnostic testing and the realities of your condition. It is impossible to take a cookie-cutter approach to the treatment of a condition as complex as Tourette Syndrome. No two brains are alike, and nor are any of our NeuroRescue Programs.

How Does the NeuroRescue Program Work?

We design your unique NeuroRescue Program to be among the most comprehensive diagnostic and therapeutic protocols available today. We create individual NeuroRescue Programs based on a comprehensive analysis of every relevant neurological system and pathway, using gold-standard, cutting edge neurodiagnostic technologies and examination procedures and state-of-the-art therapies.

We begin with your Discovery Day, wherein we perform a comprehensive history of not only your child’s condition, but your life on a timeline. This allows us to dive deeply into their case and see all of the factors that led to where they are now. It helps us uncover hidden problems and associated conditions that may be making it difficult for you to move your child’s recovery forward.

Our examination allows us to identify the areas and pathways of the brain that are involved in their tic disorder. We do this by precisely quantifying the function of the visual, vestibular, and proprioceptive systems through computerized analysis of eye movements, inner ear reflexes, and balance in a host of different sensory conditions.

We employ technologies including Videooculography and Saccadometry to measure several classes of eye movements. We use Video Head Impulse Testing to measure the function of the inner ear, and Computerized Dynamic Posturography to assess your balance in different sensory conditions.

We use NeuroSensoryMotor Integration testing to evaluate hand-eye coordination and cognition, and Virtualis testing to assess dynamic eye tracking and perception of vertical in a virtual reality environment.

We combine all of this with a comprehensive physical and neurological examination of your child’s sensory, motor, autonomic, and cognitive systems. We review any relevant laboratory testing, radiological imaging, and prior neurodiagnostic testing, and integrate that information with our findings.

We use this information to identify which parts of your child’s nervous system are working properly, which systems are struggling, and the precise point at which their systems fatigue.

We can then design a NeuroRescue Program that is unique and specific to your child’s brain, and theirs alone. The NeuroRescue Program works to rejuvenate and reintegrate the involved neurons and pathways in your child’s nervous system. It works to improve energy, endurance, and functional capacity within their fragile systems.

We use our technologies and procedures to not only see what we need to address, but also when it is time to stop and let your child rest. We address impaired neurological function from multiple angles of therapy, and provide metabolic support to improve neurological recovery.

While we cannot bring back neurons that have been lost, the NeuroRescue Program allows us to take the pathways that remain and maximize their efficiency and endurance. And by focusing on the integration of systems, we can do more than just get pathways working better, we can get them working together again. This gives us our best opportunity to return your child to living a healthy, vibrant, and fulfilling life.