Chapter 47: Tic Disorders

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Welcome to the Deep Dive.

Today we're tackling a subject that's often, well, misunderstood.

Techic disorders.

This includes Tourette Disorder, or TD.

We've gone deep into the core psychiatric literature to give you a clear, high -level picture moving past the common myths.

You know, when people hear Tourette's, they often jump straight to the most dramatic symptom coprolalia, the involuntary swearing, which, by the way, was first described way back in 1885 by Georges Gilles de la Tourette.

But focusing only on that really misses the point.

It absolutely does.

That historical view, almost a caricature, is something modern understanding is working hard to correct.

Techic disorders aren't these super rare, bizarre conditions.

They're complex neurodevelopmental disorders, and they vary a lot between people.

And here's the really crucial insight, especially for treatment.

Often it's not the tics themselves that cause the most problems.

It's the other psychiatric conditions that frequently come along with them, like ADHD and OCD.

These comorbidities often cause the biggest functional issues and, well, they really drive the treatment plan.

Right.

So this Deep Dive is basically our roadmap to understanding all that complexity.

For you listening, we're going to pin down what a ticic actually is, walk through the diagnostic criteria, explore what might cause them the neurobiology, and then really focus on today's treatment strategies, especially why behavioral therapy is often step one.

OK, so let's really unpack the definition.

What is a tic?

We're talking about rapid recurring motor movements or vocalizations.

Those are called phonic or vocal picks.

They're sudden, not rhythmic.

But here's a key technical bit.

They're considered semi -voluntary, not purely involuntary.

Exactly.

That's a critical distinction.

Semi -voluntary means you can often suppress them, at least for a short while.

But it takes effort.

Right.

There's a cost.

Definitely.

It often increases an internal tension.

Now, we classify them based on complexity.

Think of it like a scale.

And we start with simple tics.

These are pretty basic, just one muscle group or a single simple sound.

The classic example is eye blinking.

That's actually the most common first acidic people notice.

OK.

Like eye blinking, maybe a shoulder shrug, sniffing, precisely.

Throat clearing is another common simple vocal tic.

Then you have complex tics.

These are, well, more involved.

They can be slower, look more deliberate, almost purposeful sometimes.

They involve coordinated groups of muscles or sequences of sounds.

So like touching things or jumping.

I've heard of imitating gestures too.

Yes.

Touching objects, jumping, twirling, those are complex motor tics.

Imitating gestures is echopraxia.

Repeating words is palalia.

And the one everyone knows, coprolalia, is a complex vocal tic.

And kick tics aren't constant, are they?

They fluctuate.

Oh, absolutely.

They're known to wax and wane.

The frequency, the severity, even the type of a late tick can change over weeks or months.

It's very dynamic.

OK.

So if I can sort of stop it, if I really try, how is that different from, say, a compulsion in OCD that feels like an urge to?

Ah, that's where this promotory sensation comes in.

It's really fascinating and key to understanding kick tics.

Most people with tic kicks describe this uncomfortable feeling, like a tension or an itch or just something not right that builds up before the tic happens.

An urge.

A physical or mental sensation.

And the tic itself is experienced as this almost irresistible but still voluntary response to relieve that sensation.

Got it.

So it's not random.

It's like scratching an itch.

The movement is the answer to the feeling.

Perfectly put.

And often there's this just right phenomenon linked to it.

They might need to repeat the tics, sometimes multiple times, until that premonitory urge feels completely satisfied, until it feels just right.

So how does that contrast with an OCD compulsion, then?

It's subtle, especially with complex detrics that can look like compulsions.

But the core difference is the driver.

Compulsions generally are performed to reduce anxiety or prevent some feared outcome.

Think checking the stove to prevent a fire.

Tics, on the other hand, are typically performed to satisfy that internal, often localized premonitory sensory urge to get rid of that specific uncomfortable feeling.

That's the primary driver.

OK.

That urge is a really important distinction.

So how does the official rulebook, the DSM -5 -TR, take this and formalize it into diagnoses?

Right.

So the DSM -5 -TR puts these under the neurodevelopmental disorders umbrella.

And the diagnosis really boils down to two main factors.

First,

the type of tics the person has.

Are they motor, vocal, or both?

And second, the duration.

How long have they been present?

OK.

Type and duration.

Let's break that down.

Sure.

If someone has syntax, it could be single or multiple, motor and or vocal, but they've been there for less than one year.

That's classified as provisional tic disorder.

Provisional.

Makes sense.

What if they stick around longer than a year?

Then we look at the type again.

If it's only motor tics persisting for more than a year, or only vocal tics for more than a year, but critically, not both, then it's persistent motor or vocal tic disorder.

Got it.

Either, but not both, for over a year.

Exactly.

And that leads us to the diagnosis most people associate with the name.

Tourette disorder, or TD.

For TD, the criteria are specific.

The person must have multiple motor tics, A and D, at least one vocal tic.

They don't have to happen at the same time, but both types must have been present at some point.

And for TD, they also need to be there for more than a year.

Multiple motor tics and one or more vocal tics, present for more than one year.

Are there other rules that apply across all these categories?

Yes, a couple of important ones.

The onset, the start of the tics, must be before age 18.

And crucially, the symptoms can't be because of, say, substance use or another underlying medical condition, like Huntington's disease or post -viral encephalitis.

We have to rule those out.

And the waxing and waning is recognized, too.

Yes.

The criteria acknowledge that tics naturally fluctuate in frequency, severity, type, and location over time.

That's just part of the picture.

So how common are these disorders, actually?

We mentioned they're maybe not as rare as people think.

That's right.

The numbers might surprise you.

Provisional tic disorder, those shorter term tics, might affect as many as 20 percent, or one in five school -aged children at some point, though obviously most of those resolve on their own.

Wow, one in five potentially having transient tics.

What about the chronic ones?

For the full range of chronic tics disorders, including persistent tic disorder and TD,

the estimate is around one in 200 people, so still quite common.

And there's a gender difference.

Yes, a pretty noticeable one.

Males are diagnosed with Tourette's disorder about three to four times more often than females.

What about the typical course?

If a child is diagnosed, what can they expect?

Generally, the onset is around age six.

Tics tend to peak in severity between ages 10 and 12.

So early adolescence is often the toughest time.

But here's the encouraging part.

For most people, the tics significantly decrease during adolescence.

By the time they reach their early 20s, maybe 80 percent or even more find that their tics are much milder or don't cause significant functional problems anymore.

That's actually quite hopeful, but for those currently dealing with it, especially during those peak years, what's the real burden?

You mentioned comorbidities earlier.

Yes, and functionally, this is often the biggest piece of the puzzle.

The comorbidity is incredibly common and often causes more impairment than the tics themselves.

One recent estimate suggests that a staggering 86 percent of people with Tourette's disorder will have at least one other psychiatric condition during their lifetime.

86 percent.

That's huge.

What are the main ones we see?

The two big ones are ADHD and OCD.

ADHD is the most frequent partner, you could say.

It co -occurs in up to 70 percent of individuals with TD.

70 percent?

Wow.

Yeah, and what's really interesting is that the ADHD symptoms, the inattention, hyperactivity, impulsivity often show up before the tics even start, and clinically, the ADHD often predicts more overall difficulty problems in school, social issues, anger outbursts, more so than the severity of the tics is alone.

Okay, ADHD is number one.

What about OCD?

OCD, obsessive compulsive disorder, is also very common, affecting up to 50 percent of people with TD.

And there's strong evidence, especially from family and genetic studies, suggesting a shared biological vulnerability between TD and OCD.

They seem to travel together genetically.

Are there others besides ADHD and OCD?

Definitely.

We also see higher rates of mood disorders like depression and particularly anxiety disorders.

Things like separation anxiety or generalized anxiety are common.

And of course, anxiety and stress tend to make your six worse, so it can become a bit of a cycle.

It really paints a picture of complexity.

I'm thinking of a case, maybe a kid, let's call him Jeffrey, five years old.

His parents bring him in, worried about his tics.

Maybe he's blinking, shrugging, clearing his throat, maybe even making a little yelping sound.

Multiple motor, one vocal.

But when you talk to them and observe Jeffrey, yes, the tics are there.

But what's really causing chaos is his ADHD.

He can't sit still, he's not paying attention in kindergarten, he's impulsive.

In that scenario, even though the referral might have been for the critics, the treatment priority immediately shifts to managing the ADHD.

Because that's what's causing the most significant impairment for him and his family.

That's a perfect illustration.

You target what's most impairing, often that's the ADHD or the OCD.

Not necessarily the tic itself, especially if the tic is relatively mild.

Okay, let's shift gears and talk about why.

What's actually causing these critics?

We know it runs in families.

Yes, genetics play a huge role.

Tret disorder is definitely considered an inherited neurodevelopmental disorder.

Twin studies are pretty compelling here.

If one identical twin has TD,

the chance of the other twin also having it, the concordance rate, is incredibly high, somewhere between 89 % and 94%.

That's entirely genetic, then it sounds like.

So if it's genetic, what's going on in the brain?

Which circuits are involved?

The core pathway we focus on is called the corticostreatothalamic cortical circuit.

You can shorten that to CSTC circuits.

CSTC.

Think of these circuits as complex loops connecting the outer layer of the brain, the cortex, especially the frontal lobes, involved in planning and control with deeper structures called the basal ganglia.

The basal ganglia.

Those are involved in movement control, right?

Exactly.

Key parts are the caudate nucleus and the putamen, together often called the striatum.

And the thalamus acts like a relay station in this loop.

Normally, these CSTC loops help regulate and filter movements, thoughts, and urges.

They inhibit unwanted actions.

In ticcate disorders, the thinking is that these circuits are, well, dysregulated or hyperactive.

There's faulty inhibition, unwanted signals, the promontory urges, and the ticcates kind of leak through when they shouldn't.

Faulty wiring in the CSTC loops.

What about the brain chemistry?

Is it all about dopamine?

We hear that a lot.

Dopamine is definitely a key player.

There's a lot of evidence for that.

Studies have shown things like increased dopamine activity or signaling, particularly in that striatum region within the basal ganglia.

And then that fits with treatments, right?

Because drugs that block dopamine often help.

Precisely.

The fact that dopamine -blocking medications, the neuroleptics, are effective eicosuppressors, strongly supports the dopamine hypothesis.

So are there visible changes in the brain?

Can you see this on scans?

Sometimes.

Structural MRI studies have found some subtle differences, like changes in the volume of areas within these CSTC circuits, for instance.

Some studies show a slightly smaller caudate nucleus volume in people with TD.

And functional neuroimaging, like fMRI, gives us clues about activity.

It suggests that maybe the ticks themselves originate in sensory or limbic -related areas linked to that promontory urge.

And when someone tries to suppress a ticket voluntarily, you see increased activity in the prefrontal cortex, the control center, working hard to inhibit activity in the basal ganglia, specifically the putamen.

Fascinating.

Okay, we have to talk about PANDAS now.

The infectious link theory gets a lot of attention.

Yes.

PANDAS, Pediatric Autoimmune Neuropsychiatric Disorders Associated with Streptococcus.

It's definitely a topic that generates discussion and sometimes controversy.

So what's the theory behind it?

The hypothesis is that in some susceptible children, an infection with group A beta -hemolytic streptococcus, that's the bacteria that causes strep throat, can trigger a sudden dramatic onset or worsening of fresics or OCD symptoms.

How would a strep infection cause mechamethyptics?

The proposed mechanism is called molecular mimicry.

The idea is that the antibodies the child's immune system creates to fight the strep bacteria might mistakenly recognize and attack certain proteins in the brain, specifically in the basal ganglia, because they look structurally similar to parts of the bacteria.

An autoimmune attack triggered by strep.

That's the theory.

Now, it's important to stress, while some research does suggest a link between JAB -EHS infections and Tyco -CD exacerbations in some kids,

the PANDAS hypothesis itself is still debated in the scientific community.

So what does that mean for treatment?

Are doctors treating common ticks with antibiotics or immune therapies based on this?

Generally no.

That's the crucial takeaway for listeners.

While the idea is being researched, treatments based on targeting the immune system, things like intravenous immunoglobulin, IBD, or plasmapheresis, plasma exchange, have shown really inconsistent results in studies.

They carry risks, and they're definitely not considered standard clinical practice for oveolipic disorders.

They remain experimental.

Okay, so diagnosis is based on observing the ticks and getting a detailed history, right?

No blood test or brain scan can diagnose it.

Correct.

It's a clinical diagnosis.

But we do use standardized assessment tools to help us.

They're really important for objectively measuring the severity of the symptoms and tracking how well treatment is working over time.

What kind of tools?

A key one is the Yale Global Tick Severity Scale, or YGTSS.

It's widely used to read the number, frequency, intensity, complexity, and interference of both motor and vocal ticks.

And since comorbidity is so common, you'd need scales for those too.

Absolutely.

We often use specific scales for ADHD,

like the SNEP -HAVI, and for OCD, like the Children's Yale Brown Obsessive -Compulsive Scale, or CYBOCS.

Kind of finding those symptoms is just as important.

And you mentioned ruling out other conditions.

What else looks like ticks?

We need to differentiate ticks from other movement disorders.

Things like myoclonus, which are very brief, shock -like muscle jerks, or caria, which is more random, flowing movement, or dystonia, which involves sustained muscle contractions causing twisting or abnormal postures.

The history and the characteristics of the movements usually help tell them apart.

Got it.

So, once the diagnosis is clear, what's the overall approach to treatment?

What's the goal?

The philosophy has really shifted over the years.

The goal usually isn't complete elimination of every single tick.

That's often not realistic or even necessary.

The aim is functional improvement, reducing the ticks enough so they aren't causing significant distress or interfering with the person's life, school, or work.

It's about symptom relief and control.

And you stressed individualizing treatment.

Hugely important.

Treatment has to be tailored to the individual, focusing on whichever symptoms are causing the most problems for that person.

And as we said, that's frequently the comorbid ADHD or OCD symptoms, not just the ticks.

Which brings us to a major development in how we treat ticks.

Behavioral therapy is now front and center.

Yes.

This is a really significant shift in standard care.

For many people, especially those with mild to moderate ticks,

behavioral intervention is now considered the first -line treatment.

And the main evidence -based approach is called CBIT.

Correct.

Comprehensive Behavioral Intervention for Ticks, or CBIT.

There's strong evidence showing it's more effective than just supportive therapy or psychoeducation alone.

How does CBIT actually work?

What do people do in therapy?

It has few key components, but two are central.

The first is awareness training.

This involves teaching the person to become much more aware of their ticks.

And crucially, to recognize that premonitory urge or sensation that often comes just before the tick hits.

You can't change a habit if you don't notice it happening.

Okay, so first, notice the urge.

Then what?

Then comes competing response training.

This is the active part.

Once the person recognizes the urge is starting, they learn to perform a specific alternative behavior, a competing response that is physically incompatible with the tick.

Incompatible?

How so?

It means doing the competing response makes it harder, or impossible, to do the tick at the same time.

And importantly, the competing response is designed to be less noticeable, less disruptive than the tick itself.

Can you give an example?

Sure.

Let's say the tick is a noticeable head jerk to the side.

The competing response might be to gently tense the neck muscles, keeping the head straight, maybe looking straight ahead, and holding that for a minute, or until the urge fades.

Ah, so you tense the neck instead of jerking it.

Exactly.

Or if the tick is a throat clearing sound, the competing response might involve slow, diaphragmatic breathing.

It physically interferes with the throat clearing, and it relieves the urge.

Over time, practicing this helps weaken the link between the urge and the ticking,

effectively building a new, less disruptive habit.

Okay, so CBIT is first line, especially for mild to moderate cases.

But what if it's not available or not enough, or what if the ticks are really severe?

Right.

In those situations when behavioral therapy isn't accessible, or it doesn't provide sufficient relief,

or when the ticks are moderate to severe and causing significant impairment,

then pharmacotherapy, medication, becomes necessary.

What are the go -to medications now?

What's considered first line pharmacologically?

For mild to moderate ticks, especially if the person also has ADHD,

the guidelines often recommend starting with the alpha -adrenergic agonists.

These are medications like clonidine and guanfacine.

They were originally developed for blood pressure, but are quite helpful for both deutrichs and ADHD symptoms, like hyperactivity and impulsivity.

How do they work for ticks?

They affect norepinephrine pathways in the brain, which seems to help calm down some of the circuits involved in both deutrichs and ADHD.

Are there side effects to watch for?

Yes.

The main ones are sedation or tiredness, especially when starting, and potentially dizziness or low blood pressure.

So you need to monitor those carefully, usually starting with a low dose and increasing slowly.

Okay, alpha agonists for milder cases, or with ADHD.

What about more severe tics?

For moderate to severe tics, the first line pharmacologic agents are typically the atypical neuroleptics, also known as second -generation antipsychotics.

Medications like risperidone and particularly aripiprazole, which actually has FDA approval specifically for treating nickets in children and adolescents, are commonly used.

These are the dopamine blockers we mentioned earlier.

Yes, they primarily work by blocking D2 -dopamine receptors in those CSTC circuits, which directly help suppress the tick ticks.

Their advantage over older neuroleptics, like heloperidol, which is also very effective but used less now, is that these newer atypical agents also affect serotonin receptors, specifically 5 -HT2.

This generally leads to a lower risk of certain side effects, particularly the movement -related ones called extrapyramidal symptoms, or EPS.

Lower risk, but not zero risk.

What kind of monitoring is absolutely essential with these atypical neuroleptics?

This is critical.

These medications can have significant metabolic side effects.

So regular monitoring is non -negotiable.

That means routinely checking weight, calculating BMI, measuring waist circumference, and doing blood tests to monitor blood glucose levels and lipid profiles, cholesterol and triglycerides.

Metabolic screening.

Anything else?

Yes.

We also need to monitor cardiac function, usually with an ECG, because some of these medications can potentially affect heart rhythm.

Safety monitoring is paramount.

All right.

Now, what about the SSRIs, the antidepressants like Prozac or Zoloft?

Where do they fit in?

Do they treat tick ticks?

That's a really important point.

SSRIs, selective serotonin reuptake inhibitors, are generally not used to treat the ticks themselves.

They don't usually have a direct effect on hadeskirch severity.

So why use them?

We use them because they are the first -line pharmacologic treatment for the very common conditions,

OCD,

anxiety disorders, and depression.

Ah, back to treating the comorbidity.

Exactly.

And successfully treating the OCD or anxiety with an SSRI can often have an indirect benefit on the ticks.

Because as we mentioned, stress and anxiety are well -known trigger triggers or exacerbators.

So if you reduce the underlying anxiety or obsessive distress with an SSRI, the Dilla ticks often lessen as a secondary effect.

It calms the whole system down.

That makes perfect sense.

It reminds me of another common scenario.

Maybe a teenager, let's call him Mark, 13 years old.

He has TD, maybe some facial ticks and a sniffing tick, but they've actually started getting better on their own as he's gotten older.

Okay, common pattern.

But his OCD is really ramping up.

He's got contamination fears, spends hours washing his hands, lots of checking rituals.

It's completely taking over his life.

For Mark, even though he has TD, the treatment focus isn't the ticks right now, it's aggressive treatment for the OCD, probably starting with cognitive behavioral therapy, specifically exposure and response prevention, maybe adding an SSRI.

Exactly.

You monitor the ticks, but you actively treat the OCD because that's the primary source of his current distress and impairment.

It really underscores the need for targeted treatment.

So often it's not just one medication, is it?

It might be a combination.

Very often, yes.

Targeted combined pharmacotherapy is frequently necessary, especially when you have significant ticks and significant comorbidity.

For example, you might need an atypical neuroleptic like erypiprazole to manage severe pickaxe, plus an SSRI to manage co -occurring severe OCD or anxiety.

Or combining an alpha agonist with something else.

Yes, another common combination is using an alpha agonist like guanfacine, which helps both CAR ticks and ADHD somewhat, alongside a stimulant medication like methylphenidate, if the ADHD symptoms are still impairing, despite the alpha agonist.

Is it safe to use stimulants in kids with ticks, or used to be worries about that?

That's a historical concern that's largely been put to rest by research.

While stimulants can sometimes temporarily worsen ticks in a small minority of individuals, for most people with TD and comorbid ADHD, stimulants are safe and effective for treating the ADHD symptoms, and don't significantly worsen ticks long -term.

Sometimes they even help ticks indirectly by improving focus and reducing impulsivity.

Careful monitoring is needed, of course, but it's a standard approach now.

Hashtag tag tag outro.

So wrapping this up, this deep dive really highlights that Tourette Disorder isn't just about ticks.

It's a complex, inherited neurodevelopmental condition rooted in those CSTC brain circuits.

We've seen just how incredibly common and functionally important the comorbidities like ADHD and OCD are.

They often drive the impairment.

And the big shift in treatment is the rise of behavioral interventions, like CBIT, as a powerful, evidence -based first -line approach for many patients, empowering them with skills to manage their own symptoms.

Pharmacology remains crucial, especially for moderate to severe tree ticks or when comorbidities need targeting, but it's now part of a more nuanced, individualized plan.

And looking ahead, while our understanding of the genetics and neurobiology has exploded, the field isn't standing still.

Research continues into novel treatment approaches.

For those really severe treatment -resistant cases, particularly in adults, researchers are exploring things like deep brain stimulation, DBS, where electrodes are implanted in specific brain areas.

Like a pacemaker for the brain circuits involved.

Sort of, yes.

Also non -invasive techniques like transcranial magnetic stimulation, TMS, are being investigated.

And even very early -stage research into things like stem cell therapies is happening.

So that's much further off.

It shows the ongoing push for better understanding and more effective, perhaps even more targeted, interventions down the road.

Well, thank you for joining us on this deep dive into the complex world of tickle disorders.

We hope this has provided a clear and useful overview based on the core literature.