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Advanced Neurology POTS with tics versus tic-like behaviors

POTS and plays a key role in the treatment approach The exact pathophysiology of neurodevelopmental tics
to POTS, with the identification of a wide range of remains elusive, despite recent advances in understanding
predisposing, precipitating and perpetuating factors. the sensorimotor processes behind the urge to tic and
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Pharmacotherapy also plays a role in the treatment of tic expression. Dopaminergic neurotransmission is
POTS: corticosteroids (fludrocortisone), alpha-agonists primarily implicated, although other neurotransmitter
(midodrine), beta-adrenergic blockade, ivabradine, and systems are believed to be involved. For example, research
– less commonly – immunotherapy, have been used using animal models, such as knockout mice, has suggested
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for neuropathic POTS. However, the overall effects of a potential link to histidine decarboxylase deficiency.
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pharmacological therapy are modest. 2 Both genetic and environmental factors are thought to
contribute to the onset of GTS, with studies indicating a
1.2. Neurodevelopmental tics and Gilles de la heritability rate of 0.77. 26
Tourette syndrome (GTS)
1.3. Functional tic-like behaviors
Neurodevelopmental tics are sudden, rapid, recurrent,
and non-rhythmic movements (motor tics) or Functional tic-like behaviors are a subgroup of functional
sounds (vocal tics), resulting from altered pathways neurological disorder with motor manifestations
of brain development. Tic disorders are the most that resemble neurodevelopmental tics and typically
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common hyperkinetic disorder in children. GTS involve a complex clinical phenomenology, ranging
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is characterized by multiple tics as well as comorbid from repetitive twitching and jerking movements to
psychiatric disorders – especially obsessive-compulsive sounds and meaningful vocalizations. 27,28 By definition,
disorder and attention-deficit hyperactivity disorder these clinical manifestations are not consistent with
(ADHD) – in about 90% of cases. 13,15-17 The multiple a neurodevelopmental pathway and often correlate
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phenotypes of GTS can affect different aspects of with psychological stressors. Functional tics have
patients’ health-related quality of life across the traditionally been considered a condition with a relatively
lifespan. 18,19 The prevalence of GTS in youth ranges low prevalence, compared to other functional motor
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from 0.3% to 1%, while isolated tics affect up to 5% of symptoms. Comparisons with data collected before
the general population at any point in life. In most the COVID-19 pandemic show that the prevalence
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of functional tics in adolescents and young adults has
cases, the onset of neurodevelopmental tics occurs in increased dramatically since the pandemic. 29,31
childhood, between the age of 5 and 7, with a male-to-
female ratio of about 3:1 – 4:1. 20 Despite their resemblance to neurodevelopmental tics,
the clinical presentation of functional tic-like behaviors
Neurodevelopmental tics tend to spread to different reported during the COVID-19 pandemic has some peculiar
body parts following a rostrocaudal direction over the characteristics, which can assist the differential diagnosis.
years following their onset. The most common simple Functional tics are mainly diagnosed in adolescents and
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motor tics include eye blinking, facial grimacing, and young adults, with a significant preponderance of the
shoulder shrugging, while throat clearing, sniffing, and female gender. In most cases, there is no family history of
grunting are examples of simple vocal tics. More complex tics. 28,30 Both case series 32-34 and controlled studies 35-37 have
motor tics involve multiple body parts and even resemble yielded consistent findings about phenotypical differences
intentional actions, such as palilalia (repeated gestures) between the two conditions. Functional tic-like behaviors
and echopraxia (mimicking others’ movements). usually present with an acute or subacute onset, while
Complex vocal tics involve full words or phrases, such neurodevelopmental tics have a gradual onset following
as palilalia (repetition of own words) and echolalia a rostrocaudal distribution. Moreover, the clinical
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(repetition of others’ words). Socially inappropriate phenomenology of functional tic-like behaviors is more
language (coprolalia) or gestures (copropraxia) are varied, with repetitive movements involving the limbs
reported by a minority of patients (10 – 30%), typically and a higher prevalence of self-injurious tics, such as head
in association with a range of more simple motor and banging or self-hitting. Complex vocal tics in the form of
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vocal tics. A hallmark of neurodevelopmental tics is random words or swear words (coprolalia) are frequently
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the presence of premonitory urges, which are distressing part of the repertoire of functional tic-like behaviors, while
sensory experiences that precede the expression of they are reported by a subset of patients with GTS or other
tics. The sensory component is relevant to both neurodevelopmental tic disorders. 21,28,32,38 Data from a
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diagnosis and treatment since awareness of these urges recent cross-sectional study showed that both simple head
is often a prerequisite of behavioral interventions for movements such as neck jerking and complex vocalizations
neurodevelopmental tics. 23 (words/full sentences) were more likely to be reported by

Volume 4 Issue 2 (2025) 102 doi: 10.36922/an.8525