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The Phenomenology of Tics and Tic-Like Behavior in TikTok

      Abstract

      Background

      Pediatricians and pediatric subspecialists worldwide have reported a marked increase in functional (conversion) disorders with tic-like behaviors during the COVID-19 pandemic. These patients often report frequent viewing of Tourette syndrome (TS) TikTok videos, suggesting disease modeling. We aimed to evaluate tic phenomenology in videos posted on TikTok.

      Methods

      The 100 most-viewed videos under #tourettes in TikTok were randomly assigned to two of three primary reviewers (<2 years independent practice), all pediatric neurologists specializing in movement disorders, for extraction and classification of tic phenomenology. Initial disagreements were solved by consensus. If not resolved, one of five senior reviewers (>2 years independent pediatric movement disorder practice) served as a tiebreaker. In addition, two primary and one senior reviewer rated each video on a Likert scale from 1 = “All the tics are typical of TS” to 5 = “None of the tics are typical of TS”. Median scores and Spearman correlation between primary and senior reviewers were calculated.

      Results

      Six videos without tic-like behaviors were excluded. Most videos depicted coprophenomena (coprolalia: 53.2%; copropraxia: 20.2%), often with unusual characteristics. Frequently, videos demonstrated atypical phenomenology such as very strong influence by the environment (motor: 54.3%; phonic: 54.3%), aggression (19.1%), throwing objects (22.3%), self-injurious behaviors (27.7%), and long phrases (>3 words; 45.7%). Most videos portrayed atypical, nontic behaviors (median [IQR] Likert ratings: 5 [4-5]). Primary vs. senior rater scores demonstrated moderate agreement (r = 0.46; P < 0.001).

      Conclusions

      TS symptom portrayals on highly viewed TikTok videos are predominantly not representative or typical of TS.

      Keywords

      Introduction

      Tourette syndrome (TS) affects nearly 1% of the population and is characterized by persistent motor and phonic tics.
      • Singer H.S.
      • Mink J.W.
      • Gilbert D.L.
      • Jankovic J.
      Movement Disorders in Childhood.
      TS most commonly presents in boys and has a gradual onset, with tics appearing predominantly before the age of 10 years. Tics are brief, repetitive, patterned, nonrhythmic movements or vocalizations, sometimes performed in response to premonitory urges. Tics are divided into simple (e.g., blinking, grunting) and complex (e.g., gestures, words and phrases). Most tics have no clear external triggers and appear out of context.
      • Singer H.S.
      • Mink J.W.
      • Gilbert D.L.
      • Jankovic J.
      Movement Disorders in Childhood.
      Generally, the emergence of tics follows a rostrocaudal distribution. Concentration, focusing on an activity, or performing purposeful actions in the same muscles commonly decreases tics, limiting their interference with voluntary actions. Most patients with TS can voluntarily suppress their tics, albeit only momentarily.
      • Singer H.S.
      • Mink J.W.
      • Gilbert D.L.
      • Jankovic J.
      Movement Disorders in Childhood.
      Functional tic-like disorder (FTLD) is a subtype of functional movement disorder characterized by tic-like behaviors—sounds or movements that resemble tics. In contrast to TS, FTLD more commonly presents with multiple symptoms in a short time interval in adolescent and young adult females.
      • Ganos C.
      • Martino D.
      • Espay A.J.
      • Lang A.E.
      • Bhatia K.P.
      • Edwards M.J.
      Tics and functional tic-like movements: can we tell them apart?.
      Compared to tics, functional tic-like behaviors involve the arms or trunk more than the face, interfere more with voluntary actions, are less suppressible, and are more suggestible.
      • Ganos C.
      • Martino D.
      • Espay A.J.
      • Lang A.E.
      • Bhatia K.P.
      • Edwards M.J.
      Tics and functional tic-like movements: can we tell them apart?.
      ,
      • Ganos C.
      • Edwards M.J.
      • Muller-Vahl K.
      “I swear it is Tourette's!”: on functional coprolalia and other tic-like vocalizations.
      FTLD can be seen in combination with other functional neurologic symptoms and has a poor response to common tic medications.
      • Ganos C.
      • Martino D.
      • Espay A.J.
      • Lang A.E.
      • Bhatia K.P.
      • Edwards M.J.
      Tics and functional tic-like movements: can we tell them apart?.
      FTLD can also emerge in persons with TS, and in some cases, phenomenological features overlap between TS and FTLD.
      • Ganos C.
      • Martino D.
      • Espay A.J.
      • Lang A.E.
      • Bhatia K.P.
      • Edwards M.J.
      Tics and functional tic-like movements: can we tell them apart?.
      A rise in tic-referrals to movement disorders clinics has occurred during the COVID-19 pandemic. Patients with TS report worse symptoms during the pandemic,
      • Mataix-Cols D.
      • Ringberg H.
      • Fernandez de la Cruz L.
      Perceived worsening of tics in adult patients with tourette syndrome after the COVID-19 outbreak.
      possibly related to increased anxiety and confinement.
      • Robertson M.M.
      • Eapen V.
      • Rizzo R.
      • Stern J.S.
      • Hartmann A.
      Gilles de la Tourette Syndrome: advice in the times of COVID-19.
      In parallel, several groups have noticed a dramatic increase in teenagers, mainly females, presenting with sudden-onset FTLD.
      • Heyman I.
      • Liang H.
      • Hedderly T.
      COVID-19 related increase in childhood tics and tic-like attacks.
      • LaFaver K.
      • Pringsheim T.
      Going viral: social media may be increasing cases of new-onset tics [online].
      • Hull M.
      • Parnes M.
      Tics and TikTok: functional tics spread through social media.
      • Pringsheim T.
      • Martino D.
      Rapid onset of functional tic-like behaviours in young adults during the COVID-19 pandemic.
      Although a general increase in functional movement disorders has also been reported,
      • Hull M.
      • Parnes M.
      • Jankovic J.
      Increased incidence of functional (psychogenic) movement disorders in children and adults amidst the COVID-19 pandemic: a cross-sectional study.
      there has been a disproportionate increase in FTLD. Until recently, FTLD represented only a minority of functional movement disorders.
      • Demartini B.
      • Ricciardi L.
      • Parees I.
      • Ganos C.
      • Bhatia K.P.
      • Edwards M.J.
      A positive diagnosis of functional (psychogenic) tics.
      This brings the question “Why, specifically, tics?”
      • Forsyth R.J.
      Tics, TikTok and COVID-19.
      The platform TikTok (www.tiktok.com) has become very popular among teenagers.
      • Kriegel E.R.
      • Lazarevic B.
      • Athanasian C.E.
      • Milanaik R.L.
      TikTok, Tide Pods and Tiger King: health implications of trends taking over pediatric populations.
      The use of social media and the viewing of the #tourettes TikTok webpage have significantly increased during the pandemic.
      • Heyman I.
      • Liang H.
      • Hedderly T.
      COVID-19 related increase in childhood tics and tic-like attacks.
      ,
      • Gao J.
      • Zheng P.
      • Jia Y.
      • et al.
      Mental health problems and social media exposure during COVID-19 outbreak.
      The increased use of social media may have had a detrimental effect on mental health during the pandemic.
      • Gao J.
      • Zheng P.
      • Jia Y.
      • et al.
      Mental health problems and social media exposure during COVID-19 outbreak.
      Many patients with FTLD report watching TS videos or posting videos of their movements in TikTok. This suggests a potential association between TikTok and the rise in FTLD.
      • Heyman I.
      • Liang H.
      • Hedderly T.
      COVID-19 related increase in childhood tics and tic-like attacks.
      • LaFaver K.
      • Pringsheim T.
      Going viral: social media may be increasing cases of new-onset tics [online].
      • Hull M.
      • Parnes M.
      Tics and TikTok: functional tics spread through social media.
      • Pringsheim T.
      • Martino D.
      Rapid onset of functional tic-like behaviours in young adults during the COVID-19 pandemic.
      The accuracy of medical videos in social media is highly variable. In a previous study, 66% of videos portraying movement disorders were qualified as functional by experts in the field.
      • Stamelou M.
      • Edwards M.J.
      • Espay A.J.
      • et al.
      Movement disorders on YouTube--caveat spectator.
      However, there is limited information on the characteristics of the current videos available in TikTok. The goal of this study is to characterize and evaluate the phenomenology of tics and tic-like behavior portrayed in TikTok.

      Methods

      Search strategy

      Our video search was performed on a single day on March 27th, 2021. Before starting the search, the computer's cache/cookies and search history were cleared to prevent the effects of previous searches on our sample. We looked for all the videos under #tourettes. We chose this hashtag because it is commonly used in videos portraying TS and recently had an increase in popularity.
      We selected the 100 most-viewed videos. This number represents a reasonable sample of the videos that would be seen by a person searching for TS in TikTok while maintaining the feasibility of evaluating a large number of videos. Duplicated videos or videos that did not show tics were excluded. The number of comments and “likes” was recorded for each video. Of note, some of the videos portrayed the same subject at different times. We did not limit our search to only one video per subject because we wanted our sample to realistically represent all available videos in TikTok.

      Video review

      All reviewers were pediatric neurologists specializing in movement disorders. Primary reviewers (A.Z.V., A.B., and J.G.) had less than 2 years of independent practice. Senior reviewers (S.W., L.T., R.L., P.B., and D.G.) were more experienced specialists. An initial list of common, atypical, and severe tic phenomenology was generated for use in quantifying phenomenology in videos. Typical features were defined as those commonly seen in TS, whereas atypical features were defined as those seen more frequently in FTLD. This was based on a prior review by Ganos et al.
      • Ganos C.
      • Martino D.
      • Espay A.J.
      • Lang A.E.
      • Bhatia K.P.
      • Edwards M.J.
      Tics and functional tic-like movements: can we tell them apart?.
      and our clinical experience, which was recently corroborated by Paulus et al's comparison of phenomenology between tics in TS and FTLD in the setting of the COVID-19 pandemic.
      • Paulus T.
      • Baumer T.
      • Verrel J.
      • et al.
      Pandemic tic-like behaviors following social media consumption.
      We rated the presence or absence of each feature in the entire video, allowing for the possibility of multiple tics per video. A pilot was conducted with 10 videos. After analysis, primary reviewers discussed difficulties in data extraction. As a result, some tic-like characteristics judged too difficult to reliably and accurately assess in short and edited videos were eliminated. The final list of tic phenomenology and definitions used for data extraction is presented in the Supplementary Materials.
      We utilized the construct “context-dependent tics” (CDT) in our data extraction to classify behaviors that appeared to be strongly influenced by the environment. This included two features that frequently occurred together and were difficult to assess separately based only on short videos. The first are behaviors that are very specific to the external situation of the subject: for example, involuntary phrases that followed the content of an ongoing conversation or complex motor behaviors using objects in the environment. The second are behaviors that are triggered by an external stimulus, such as clapping specifically when seeing a dog; these have been called stimulus-bound or reflex tics in the TS literature.
      • Janik P.
      • Milanowski L.
      • Szejko N.
      Phenomenology and clinical correlates of stimulus-bound tics in Gilles de la Tourette syndrome.
      Similar to other studies, we excluded ecophenomena (repeating other people's words or actions) and paliphenomena (repeating one's own words or actions) from this category.
      • Janik P.
      • Milanowski L.
      • Szejko N.
      Phenomenology and clinical correlates of stimulus-bound tics in Gilles de la Tourette syndrome.
      Each video was randomly assigned to two primary reviewers who independently quantified and extracted the characteristics of tics or tic-like behaviors, blinded to each other's initial assessment. In cases where disagreements occurred, reviewers were then unblinded and able to review and discuss the other's interpretation and attempted to reach a consensus. If this was not achieved, a senior reviewer was the tiebreaker. Any movement or sound that was portrayed as a tic and is likely to be interpreted as a tic by a lay audience was included. Qualitative descriptions of other patterns of tics in these videos were also obtained.
      In addition to evaluating tic phenomenology, all videos were rated globally using a Likert scale from 1 = “All of the movements or sounds portrayed are typical of a primary tic disorder such as Tourette syndrome” to 5 = “None of the movements or sounds portrayed are typical of a primary tic disorder such as Tourette syndrome”. Each video was randomly assigned to be rated by 2 primary reviewers, who also evaluated tic phenomenology, and 1 senior reviewer. Since this is a subjective rating, all reviewers were kept blind to each other's assessment and no tiebreaker process was used for this part. As a result, each video had 3 Likert scores assigned, two from primary reviewers and one from a senior reviewer. We used a Likert scale, instead of a dichotomous variable, recognizing that a complete differentiation of these types of behaviors is impossible based on short videos and that there is phenomenology overlap between TS and FTLD.

      Ethical considerations

      All videos included were publicly accessible in social media and therefore considered part of the public domain. Consistent with other studies of publicly available material in social media, consent from creators and ethics approval were not obtained.
      • Herrick S.S.C.
      • Hallward L.
      • Duncan L.R.
      “This is just how I cope”: an inductive thematic analysis of eating disorder recovery content created and shared on TikTok using #EDrecovery.
      ,
      • Fat M.J.
      • Sell E.
      • Barrowman N.
      • Doja A.
      Public perception of tourette syndrome on YouTube.
      No identifiable information is included in the article.

      Data analysis

      Tic phenomenology was summarized by percentages of videos representing each feature. In addition, qualitative descriptions are provided. An additional analysis based on frequency of videos posted by the same username is presented in the Supplementary Materials.
      Each Likert score was included in the analysis independently. Each video had 3 Likert scores assigned by different reviewers. These were summarized using medians and interquartile range (IQR). An additional analysis was performed to assess the Likert scores per level of experience. For this analysis, Likert scale ratings of both primary reviewers were averaged for comparison with the senior reviewer. Correlation between mean primary reviewers' score and senior reviewer's score was calculated using Spearman correlation.

      Results

      Videos

      The 100 videos in the initial search were posted by 37 different users. The median of the number of videos posted by an individual username was 1 (IQR: 1-2, range: 1-34). On average, each video had 2,060,379 “likes” and 47,922 comments. None of the videos were duplicated, and 6 did not show tics. In addition, 2 videos were removed from the TikTok webpage before all reviewers could assign a Likert score. Therefore, we included 94 videos for the assessment of tic phenomenology and 92 videos for Likert scale scoring.

      Phenomenology

      Table 1 shows the frequencies of the portrayed tic-like phenomenology, and Table 2 presents illustrative examples. Many videos showed a very high number of different tics in a single day (>10 tics; 52.1%). Coprophenomena was frequently portrayed (copropraxia: 20.2%; coprolalia: 53.2%). Context-dependent coprophenomena and coprolalia consisting of long phrases (>3 words) were the most common atypical characteristics noted. Many subjects reacted positively to coprophenomena and used it for a comedic effect. In some videos, coprophenomena was directed at a specific person. Some subjects replaced words in a sentence or song lyric with obscene words while keeping the same number of syllables and/or rhythm of the sentence or song.
      TABLE 1.Phenomenology of Tic-Like Behavior in TikTok Videos
      PhenomenologyTotal
      Total N of videos with tics94
      More than 10 different tics in a single day49 (52.1%)
      Motor tics92 (97.9%)
       Area of the body involved
      Face and neck88 (93.6%)
      Rest of the body78 (83.0%)
       Motor tics disrupt a voluntary action36 (38.3%)
       Copropraxia19 (20.2%)
      Prolonged or sustained copropraxia (>3 seconds)
      Percentages reported are based on the total videos of the subcategory.
      1 (5.3%)
      Context-dependent copropraxia
      Percentages reported are based on the total videos of the subcategory.
      4 (21.1%)
      High number of different types of copropraxia (>3)
      Percentages reported are based on the total videos of the subcategory.
      0 (0.0%)
       Subject reacts positively to copropraxia
      Percentages reported are based on the total videos of the subcategory.
      3 (15.8%)
       Echopraxia2 (2.1%)
       Palipraxia0 (0.0%)
       Context-dependent motor tics51 (54.3%)
       Aggression to others18 (19.1%)
       Throwing objects21 (22.3%)
       Self-injurious behaviors26 (27.7%)
       Prolonged or sustained motor tics (>3 seconds)4 (4.3%)
       Tics causing falls6 (6.4%)
      Phonic tics83 (88.3%)
       Phonic tics disrupt speech8 (8.5%)
       Coprolalia50 (53.2%)
      Coprolalia consisting of long phrases (>3 words)
      Percentages reported are based on the total videos of the subcategory.
      20 (40.0%)
      Context-dependent coprolalia
      Percentages reported are based on the total videos of the subcategory.
      25 (50.0%)
      High number of different types of coprolalia (>3)
      Percentages reported are based on the total videos of the subcategory.
      6 (12.0%)
      Subject reacts positively to coprolalia
      Percentages reported are based on the total videos of the subcategory.
      11 (22.0%)
       Echolalia5 (5.3%)
       Palilalia3 (3.2%)
       Context-dependent phonic tics51 (54.3%)
       Long phrases (>3 words)43 (45.7%)
      Percentages reported are based on the total videos of the subcategory.
      TABLE 2.Illustrative Examples of Tic-Like Behavior in TikTok
      ExamplesAdditional Atypical Features
      Some features are not included in Table 1 because they were difficult to assess systematically in all videos. However, we included them as qualitative observations in some videos.
      Coprophenomena
       Saying “F∗ck off, you b∗tch”.Long phrases (>3 words)
       Saying “dumb f∗ck” instead of “dim sum” while cooking dim sums.Replaces words for coprolalia of similar syllables.
       Replacing parts of the lyrics of the “Bob the Builder” cartoon theme song for “F∗ck off right now!”Context-dependent, long phrases (>3 words), follows the tune of the song.
       Saying “You chunky ass b∗tch” directed to a woman.Context-dependent, long phrases (>3 words), directed to a specific person.
      Context-dependent
       Saying “Simba” while smearing a substance on own forehead, then saying “Mufasa” while smearing the same substance on another person's forehead. The subject appears frustrated.Nonstereotyped, complex, refers to a popular character (in the Lion King movie, a fruit is smeared on Simba's forehead. Mufasa is Simba's dad), ego-dystonic.
      Ego-dystonic tics are tics that appeared to be intrusive and not in line with the individual's values and resulted in frustration or embarrassment.
       Saying “Mix it with your glasses” while stirring a mixture of slime using the subject's glasses. Then saying “wear them again” while putting the glasses back without cleaning them. The subject appears frustrated.Nonstereotyped, complex, subject narrates the ongoing motor behavior, ego-dystonic.
      Ego-dystonic tics are tics that appeared to be intrusive and not in line with the individual's values and resulted in frustration or embarrassment.
       Interrupting a person that says: “Believe it or not (…) I'm…” by saying “I'm gay. I knew it!”.Nonstereotyped, long phrase (>3 words), follows context of the conversation.
       Responding to a person that asks: “Do you know what is really annoying?” by saying “You” and then apologizing.Follows the context of the conversation, ego-dystonic.
      Ego-dystonic tics are tics that appeared to be intrusive and not in line with the individual's values and resulted in frustration or embarrassment.
       Saying: “Ew stop. My ears are bleeding” as a response to someone else's singing and then apologizing.Follows context of the conversation, long phrase (>3 words), ego-dystonic.
      Ego-dystonic tics are tics that appeared to be intrusive and not in line with the individual's values and resulted in frustration or embarrassment.
       Elbowing, head butting, and karate-chopping a Jenga tower in a non-stereotyped matter while producing several vocalizations. The subject loses the game as a result.Nonstereotyped, complex, ego-dystonic.
      Ego-dystonic tics are tics that appeared to be intrusive and not in line with the individual's values and resulted in frustration or embarrassment.
       Saying: “Ejaculate on the board” while pouring a white sauce in a cutting board. The subject appears frustrated.Non-stereotyped, complex, long phrase (>3 words), ego-dystonic.
      Ego-dystonic tics are tics that appeared to be intrusive and not in line with the individual's values and resulted in frustration or embarrassment.
       Saying: “It's a hat” while putting a hot pan lid on own head causing pain.Non-stereotyped, complex, self-injurious behavior, ego-dystonic.
      Ego-dystonic tics are tics that appeared to be intrusive and not in line with the individual's values and resulted in frustration or embarrassment.
       Changing multiple parts of the lyrics of the nursery rhyme Old McDonald. For example, changing “Everywhere a moo-moo” for “Everywhere a BigMac” or adding “called Peppa” after “and on his farm he had a pig”. Subject appears frustrated.Nonstereotyped, follows the tune of the song, refers to popular characters (Peppa is a cartoon pig), ego-dystonic.
      Ego-dystonic tics are tics that appeared to be intrusive and not in line with the individual's values and resulted in frustration or embarrassment.
      Aggression to others
       Slapping someone's arm while saying “don't touch me” followed by an apology, then screaming “I said don't!” followed by a second apology. The other person was doing the subject's hair.Nonstereotyped, second phrase refers to first phrase.
       Slapping another person repeatedly in a non-stereotyped matter for a few seconds and then returning to regular activities.Nonstereotyped.
      SelfiInjurious behavior
       Putting makeup, slime, or other non-edible or injurious objects inside the mouth or on the tongue.Nonstereotyped, context-dependent.
       Hitting and slapping different parts of the body in a non-stereotype matter for a few seconds and then continuing with regular activities.Nonstereotyped
       Jaw locked causing to bite lips for ∼30 minutes resulting in injuries to the lips.Prolonged motor tic (>3 seconds).
      Throwing objects
       Throwing different objects like eggs, milk, or flour while cooking or baking.Nonstereotyped, context-dependent.
       Performing a “challenge” consisting of holding an egg without dropping it for as long as possible. Often the challenge ends with the subject throwing the egg after only a few seconds.Context-dependent.
      Long phrases
       Saying “That's not a tic” or “That's not a tic, I just dislike you” after an offensive tic-like behavior.Context-dependent, phrase refers to a previous tic-like behavior.
       Saying: “I bite men” followed by “Thank god you are not a man” while pointing at someone.Context-dependent, second phrase refers to first phrase.
      Some features are not included in Table 1 because they were difficult to assess systematically in all videos. However, we included them as qualitative observations in some videos.
      Ego-dystonic tics are tics that appeared to be intrusive and not in line with the individual's values and resulted in frustration or embarrassment.
      CDT were also frequently portrayed (motor: 54.3%; phonic: 54.3%). Commonly, CDT were complex actions and resulted in frustration or embarrassment (e.g., were ego-dystonic). Phonic CDT were often portrayed as unwanted, occasionally insulting, verbal responses that were consistent with the context of an ongoing conversation. Other common patterns of CDT include complex motor actions while verbally describing such action or referring to popular characters (e.g., mentioning a popular farm animal cartoon while cooking that specific type of meat). In extreme cases, videos showed subjects almost constantly reacting involuntarily to the environment, giving the appearance of a complete loss of inhibition.
      Aggression toward other people or objects, present in 19.1% of videos, was often nonstereotyped and, occasionally, accompanied by complex verbal behavior. Similarly, self-injurious behavior (SIB), present in 27.7% of videos, was commonly nonstereotyped. Putting nonedible or injurious material inside the mouth or on the tongue was seen frequently. Throwing objects, present in 22.3% of videos, was commonly seen in the context of cooking or baking. A “challenge” consisting of holding an egg for as long as possible was portrayed by multiple subjects. Often, the challenge ended with the subject throwing the egg after a few seconds. Long phrases (>3 words) were commonly seen (45.7% of videos) and were frequently context-dependent. In some cases, tic-like behavior consisting of prolonged phrases referenced a previous behavior, such as denying that the previous behavior was a tic. We found one example of a motor tonic tic that was portrayed as lasting ∼30 minutes causing injuries to the subject.
      In our qualitative assessment, we noted that many videos contained a greater number of occurrences of tic-like behaviors involving the trunk and extremities than of the head and neck. Since our analysis is based on the presence or absence of a feature in the entirety of a video, this unexpected predominance of behaviors involving the trunk and extremities is not apparent in Table 1. We did not extract the complexity of tic-like behaviors due to difficulty in assessing it accurately in all videos. However, we noted that many videos showed a mixture of simple and complex tic-like behavior with a preponderance of complex behaviors.

      Likert score

      The median Likert scale score was 5 (IQR: 4-5) (Fig). The distribution of Likert scores was similar between different levels of experience of reviewers (Supplementary Figure). The Spearman correlation coefficient between primary and senior reviewers was 0.46 (P < 0.001).
      Figure thumbnail gr1
      FIGUREBar graph of the Likert scale scores. Likert scores from all reviewers were combined, and the percentage of each score is shown. The color version of this figure is available in the online edition. TS, Tourette syndrome.

      Discussion

      In this assessment of TikTok videos indexed in March 2021 by “#tourettes,” we found a high frequency of movements, vocalizations, and severe behavioral disturbances more characteristic of functional tic-like behaviors than of tics. Both primary and senior reviewers judged most videos as poorly consistent with a primary tic disorder (Likert score: 4-5). Importantly, this video review is not equivalent to a clinical evaluation of the individuals in these videos. A clinical in-person assessment would include many elements not obtainable solely through video review. However, it does show that these videos could be misleading to the general public.
      Coprophenomena, seen in ∼15% of patients with TS,
      • Freeman R.D.
      • Zinner S.H.
      • Muller-Vahl K.R.
      • et al.
      Coprophenomena in tourette syndrome.
      were over-represented in these videos (copropraxia: 20.2%; coprolalia: 53.2%) and often had atypical features. Coprophenomena portrayed in these videos was frequently context-dependent and included long phrases. Although urges to make insulting remarks about a person's trait can be seen in TS,
      • Eddy C.M.
      • Cavanna A.E.
      On being your own worst enemy: an investigation of socially inappropriate symptoms in Tourette syndrome.
      coprophenomena in TS generally consists of short words or movements presenting out of context and without clear triggers.
      • Ganos C.
      • Edwards M.J.
      • Muller-Vahl K.
      “I swear it is Tourette's!”: on functional coprolalia and other tic-like vocalizations.
      CDT were also very frequent (motor: 54.3%; phonic: 54.3%). Tic-like behavior that is very consistent with the situation of the subject is more frequently seen with FTLD than TS.
      • Mainka T.
      • Balint B.
      • Govert F.
      • et al.
      The spectrum of involuntary vocalizations in humans: a video atlas.
      Tics triggered by an external stimulus are present in ∼20% of patients with TS, but, unlike tics portrayed in these videos, they are more commonly simple and not ego-dystonic (i.e., tics that appear intrusive and not in line with the individual's values and resulted in frustration or embarrassment).
      • Janik P.
      • Milanowski L.
      • Szejko N.
      Phenomenology and clinical correlates of stimulus-bound tics in Gilles de la Tourette syndrome.
      Rage attacks, which might include physical aggression, are present in 20-67% of patients with TS,
      • Conte G.
      • Valente F.
      • Fioriello F.
      • Cardona F.
      Rage attacks in tourette syndrome and chronic tic disorder: a systematic review.
      and SIBs are seen in 35% of patients with TS.
      • Stafford M.
      • Cavanna A.E.
      Prevalence and clinical correlates of self-injurious behavior in Tourette syndrome.
      However, these behaviors are not always tics and can also be caused by obsessive-compulsive thoughts, mood disorders, or impulsivity.
      • Conte G.
      • Valente F.
      • Fioriello F.
      • Cardona F.
      Rage attacks in tourette syndrome and chronic tic disorder: a systematic review.
      • Stafford M.
      • Cavanna A.E.
      Prevalence and clinical correlates of self-injurious behavior in Tourette syndrome.
      • Cheung M.-Y.C.
      • Shahed J.
      • Jankovic J.
      Malignant tourette syndrome.
      • Szejko N.
      • Muller-Vahl K.R.
      Challenges in the diagnosis and assessment in patients with tourette syndrome and comorbid obsessive-compulsive disorder.
      • Mathews C.A.
      • Waller J.
      • Glidden D.
      • et al.
      Self injurious behaviour in Tourette syndrome: correlates with impulsivity and impulse control.
      Additionally, aggression to others due to different psychiatric disorders, including functional and factitious disorder, can be misdiagnosed as TS.
      • Kurvits L.
      • Mainka T.
      • Cavanna A.E.
      • Kühn A.A.
      • Ganos C.
      Aggression toward others misdiagnosed as primary tics.
      We found a high number of videos showing aggression to others (19.1%) and SIBs (27.7%) with atypical features for a tic. Although we were unable to define the exact cause of these behaviors, most videos implied or explicitly said that these were tics. This is particularly worrisome giving the modeling phenomenon that has been reported in recent patients with FTLD.
      • Hull M.
      • Parnes M.
      Tics and TikTok: functional tics spread through social media.
      Other atypical phenomenology noted in the videos includes a very high number of different tics, preponderance of complex behaviors or behaviors involving the trunk and extremities, tic-like behaviors consisting of long phrases, and tic-like behaviors consisting of throwing objects. In TS, simple tics are more common than complex tics,
      • Ganos C.
      • Munchau A.
      • Bhatia K.P.
      The semiology of tics, Tourette's, and their associations.
      • Leckman J.F.
      Phenomenology of tics and natural history of tic disorders.
      • Leckman J.F.
      • Bloch M.H.
      • Scahill L.
      • King R.A.
      Tourette syndrome: the self under siege.
      and tics affecting the eyes, face, and neck are more common than tics affecting the rest of the body.
      • Ganos C.
      • Bongert J.
      • Asmuss L.
      • Martino D.
      • Haggard P.
      • Münchau A.
      The somatotopy of tic inhibition: where and how much?.
      Although phonic tics can include phrases,
      • Leckman J.F.
      • Bloch M.H.
      • Scahill L.
      • King R.A.
      Tourette syndrome: the self under siege.
      these are generally short. In our experience, tics consisting of throwing objects are very rare, but we could not find systematic evaluations of this feature.
      A recent single-center analysis of TS TikTok videos was conducted to assess phenomenology.
      • Olvera C.
      • Stebbins G.T.
      • Goetz C.G.
      • Kompoliti K.
      TikTok tics: a pandemic within a pandemic.
      Interestingly, the authors extracted videos the same week that we did; therefore, they likely analyzed similar sets of videos as the current study. The authors in this study focused on the most popular influencers. They noted a higher frequency of female subjects. They also found high rates of coprophenomena, complex tics, tics involving extremities, tics causing interference with actions, and SIBs. In addition to these findings, our study added further details about atypical phenomenology and included overall impression of videos using a Likert scale by reviewers from multiple centers. Considering both studies, there is mounting evidence that multiple specialists from different centers, including adult and child neurologists, have come to similar conclusions about the accuracy of TS TikTok videos.
      The present study was prompted by the authors’ clinical experience with an unexplained surge in adolescents presenting to our clinics with functional tic-like behaviors. The atypical phenomenology in the videos we reviewed has been frequently reported in patients with FTLD during the COVID-19 pandemic.
      • LaFaver K.
      • Pringsheim T.
      Going viral: social media may be increasing cases of new-onset tics [online].
      • Hull M.
      • Parnes M.
      Tics and TikTok: functional tics spread through social media.
      • Pringsheim T.
      • Martino D.
      Rapid onset of functional tic-like behaviours in young adults during the COVID-19 pandemic.
      Some patients present with a tic that is frequently seen in TikTok but otherwise would be rarely seen,
      • LaFaver K.
      • Pringsheim T.
      Going viral: social media may be increasing cases of new-onset tics [online].
      ,
      • Pringsheim T.
      • Martino D.
      Rapid onset of functional tic-like behaviours in young adults during the COVID-19 pandemic.
      and some unusual tics were shared by different subjects in these videos.
      • Olvera C.
      • Stebbins G.T.
      • Goetz C.G.
      • Kompoliti K.
      TikTok tics: a pandemic within a pandemic.
      All authors have noticed the same trends in our clinical practice.
      In several recent studies, others have suggested a possible causal relation between TikTok TS videos and FTLD.
      • Heyman I.
      • Liang H.
      • Hedderly T.
      COVID-19 related increase in childhood tics and tic-like attacks.
      • LaFaver K.
      • Pringsheim T.
      Going viral: social media may be increasing cases of new-onset tics [online].
      • Hull M.
      • Parnes M.
      Tics and TikTok: functional tics spread through social media.
      ,
      • Hull M.
      • Parnes M.
      • Jankovic J.
      Increased incidence of functional (psychogenic) movement disorders in children and adults amidst the COVID-19 pandemic: a cross-sectional study.
      One hypothesis is that the rise in FTLD is caused by “social contagion” or modeling.
      • Hull M.
      • Parnes M.
      Tics and TikTok: functional tics spread through social media.
      ,
      • Forsyth R.J.
      Tics, TikTok and COVID-19.
      While to date we do not have strong evidence to support this hypothesis, disease modeling is seen in functional neurologic disorders, and modeling of tics portrayed in social media has been reported in a previous case of mass functional (psychogenic) illness.
      • Bartholomew R.E.
      • Wessely S.
      • Rubin G.J.
      Mass psychogenic illness and the social network: is it changing the pattern of outbreaks?.
      ,
      • Pellicciari R.
      • Superbo M.
      • Gigante A.F.
      • Livrea P.
      • Defazio G.
      Disease modeling in functional movement disorders.
      Alternatively, since some of the teenagers diagnosed with FTLD had a history of mild tics in childhood, echophenomena in genetically susceptible patients has also been postulated to explain some cases.
      • LaFaver K.
      • Pringsheim T.
      Going viral: social media may be increasing cases of new-onset tics [online].
      Although infectious or postinfectious etiologies can present fulminantly, a recent review of movement disorders associated with proven COVID-19 infection found no cases of tics or tic-like events.
      • Ghosh R.
      • Biswas U.
      • Roy D.
      • et al.
      De novo movement disorders and COVID-19: exploring the interface.
      Although similarities between the atypical features in these videos and current patients with FTLD have been noticed, it is unclear if the most common atypical features seen in our analysis are also frequently present in most subjects with FTLD. Extrapolating our findings to clinic patients should be done with caution. There have been no studies directly comparing the features seen in these videos and the phenomenology of patients with TS and FTLD in clinic. Such study would provide valuable information of this phenomenon.
      Given the recent reports of a high number of patients presenting with FTLD misdiagnosed with TS, patients with atypical characteristics should be evaluated by experienced clinicians to make sure the diagnosis is correct. If a diagnosis of FTLD is made, then we recommend stopping unnecessary tic medications and focusing on functional interventions. Patients should resume regular school and pleasurable activities and work on healthy habits including healthy eating, sleep hygiene, good hydration, and regular exercise. Underlying mental health problems such as anxiety, especially social anxiety, mood disorders, and recent stressors should be assessed and addressed. Behavioral interventions such as cognitive behavioral therapy and habit reversal therapy can also be effective in managing symptoms.
      Finally, in the treatment of TS and tic-like behaviors, it is recommended to minimize attention (negative or positive) on tics or tic-like behaviors.
      • Woods D.W.
      Managing Tourette Syndrome: A Behavioral Intervention for Children and Adults: Therapist Guide.
      ,
      • Hedderly T.
      • Heyman I.
      • Ganos C.
      • et al.
      Neurosymptoms.org functional tics factsheet [online].
      Increased attention to the abnormal behaviors can result in exacerbation and perpetuation of symptoms in both disorders but is more prominent in FTLD.
      • Ganos C.
      • Martino D.
      • Espay A.J.
      • Lang A.E.
      • Bhatia K.P.
      • Edwards M.J.
      Tics and functional tic-like movements: can we tell them apart?.
      These videos often show excessive attention to the person with tics. This effect can also extend to viewers reinforcing abnormal behaviors. We recommend that patients with FTLD avoid watching TS TikTok videos or videos showing neurologic symptoms for at least 4 weeks. Additionally, the effect of these videos in patients with TS has not been studied.
      Our study has several limitations. First, behaviors due to obsessive-compulsive symptoms, disinhibition, or impulsivity can resemble tics and may have been mischaracterized by the reviewers. However, the included events were portrayed as tics and are likely to be interpreted as such by a lay audience. Second, the categorization of tics based on short videos is imperfect.
      • Paszek J.
      • Pollok B.
      • Biermann-Ruben K.
      • et al.
      Is it a tic?--Twenty seconds to make a diagnosis.
      ,
      • van der Salm S.M.
      • de Haan R.J.
      • Cath D.C.
      • van Rootselaar A.F.
      • Tijssen M.A.
      The eye of the beholder: inter-rater agreement among experts on psychogenic jerky movement disorders.
      To limit subjectivity, multiple reviewers evaluated each video. Third, we only found a moderate correlation between reviewers of different experience. This is likely due to mild discrepancies in scoring (e.g., score of 4 vs score of 5). This discrepancy also speaks to the difficulty in fully differentiating TS and FTLD based on short videos. Fourth, we did not separate our analysis by specific subject portrayed which could result in an over-representation of the most popular influencers. However, this parallels the experience of the general population as they are likely to encounter the most popular videos more frequently.
      Finally, among several factors we could not assess by video and which therefore raise questions for future studies, we wish to suggest the possible role of secondary gain as a contributor to the high prevalence of severe, atypical features. A previous study found that negative portrayals of TS are more popular in social media.
      • Fat M.J.
      • Sell E.
      • Barrowman N.
      • Doja A.
      Public perception of tourette syndrome on YouTube.
      We note the possibility that the high number of views, comments, and likes for these videos may have resulted in psychological and/or economic benefits to the individuals posting the videos. While many individuals in these videos express an interest in increasing TS awareness, the present analysis suggests a risk of creating a highly inaccurate perception of TS. This problem may exist for other disorders, as a recent study reported that some TikTok videos intended to create eating disorders awareness could be interpreted as portraying pro-eating disorders messages.
      • Herrick S.S.C.
      • Hallward L.
      • Duncan L.R.
      “This is just how I cope”: an inductive thematic analysis of eating disorder recovery content created and shared on TikTok using #EDrecovery.

      Conclusion

      In sum, current TikTok videos are poorly representative of TS and could be misleading to the general public. The detailed description in this article is intended to help pediatricians, child psychiatrists, and child neurologists recognize this atypical phenomenology to guide additional inquiry about social media exposure and treatment. Videos of tics are a notable example of the proliferation of misleading videos portraying medical conditions during the pandemic. However, similar trends have been reported in other neurologic and psychiatric disorders.
      • Herrick S.S.C.
      • Hallward L.
      • Duncan L.R.
      “This is just how I cope”: an inductive thematic analysis of eating disorder recovery content created and shared on TikTok using #EDrecovery.
      ,
      • Kim D.D.
      • Kung C.S.
      • Perez D.L.
      Helping the public understand adverse events associated with COVID-19 vaccinations: lessons learned from functional neurological disorder.
      Although our findings could suggest an association between TikTok videos and the current spike in FTLD, our study was not designed to evaluate this. Further research is needed to define the relationship between social media and FTLD.

      Supplementary data

      References

        • Singer H.S.
        • Mink J.W.
        • Gilbert D.L.
        • Jankovic J.
        Movement Disorders in Childhood.
        2nd ed. Elsevier/AP, Academic Press is an Imprint of Elsevier, Amsterdam; Boston2016
        • Ganos C.
        • Martino D.
        • Espay A.J.
        • Lang A.E.
        • Bhatia K.P.
        • Edwards M.J.
        Tics and functional tic-like movements: can we tell them apart?.
        Neurology. 2019; 93: 750-758
        • Ganos C.
        • Edwards M.J.
        • Muller-Vahl K.
        “I swear it is Tourette's!”: on functional coprolalia and other tic-like vocalizations.
        Psychiatry Res. 2016; 246: 821-826
        • Mataix-Cols D.
        • Ringberg H.
        • Fernandez de la Cruz L.
        Perceived worsening of tics in adult patients with tourette syndrome after the COVID-19 outbreak.
        Mov Disord Clin Pract. 2020; 7: 725-726
        • Robertson M.M.
        • Eapen V.
        • Rizzo R.
        • Stern J.S.
        • Hartmann A.
        Gilles de la Tourette Syndrome: advice in the times of COVID-19.
        F1000Res. 2020; 9: 257
        • Heyman I.
        • Liang H.
        • Hedderly T.
        COVID-19 related increase in childhood tics and tic-like attacks.
        Arch Dis Child. 2021; (Online ahead of print)
        • LaFaver K.
        • Pringsheim T.
        Going viral: social media may be increasing cases of new-onset tics [online].
        (Available at:)
        • Hull M.
        • Parnes M.
        Tics and TikTok: functional tics spread through social media.
        Mov Disord Clin Pract. 2021; 8: 1248-1252
        • Pringsheim T.
        • Martino D.
        Rapid onset of functional tic-like behaviours in young adults during the COVID-19 pandemic.
        Eur J Neurol. 2021; 36: 2707-2713
        • Hull M.
        • Parnes M.
        • Jankovic J.
        Increased incidence of functional (psychogenic) movement disorders in children and adults amidst the COVID-19 pandemic: a cross-sectional study.
        Neurol Clin Pract. 2021; 11: e686-e690
        • Demartini B.
        • Ricciardi L.
        • Parees I.
        • Ganos C.
        • Bhatia K.P.
        • Edwards M.J.
        A positive diagnosis of functional (psychogenic) tics.
        Eur J Neurol. 2015; 22: 527-e536
        • Forsyth R.J.
        Tics, TikTok and COVID-19.
        Arch Dis Child. 2021; (Online ahead of print)
        • Kriegel E.R.
        • Lazarevic B.
        • Athanasian C.E.
        • Milanaik R.L.
        TikTok, Tide Pods and Tiger King: health implications of trends taking over pediatric populations.
        Curr Opin Pediatr. 2021; 33: 170-177
        • Gao J.
        • Zheng P.
        • Jia Y.
        • et al.
        Mental health problems and social media exposure during COVID-19 outbreak.
        PLoS One. 2020; 15e0231924
        • Stamelou M.
        • Edwards M.J.
        • Espay A.J.
        • et al.
        Movement disorders on YouTube--caveat spectator.
        N Engl J Med. 2011; 365: 1160-1161
        • Paulus T.
        • Baumer T.
        • Verrel J.
        • et al.
        Pandemic tic-like behaviors following social media consumption.
        Mov Disord. 2021; 36: 2932-2935
        • Janik P.
        • Milanowski L.
        • Szejko N.
        Phenomenology and clinical correlates of stimulus-bound tics in Gilles de la Tourette syndrome.
        Front Neurol. 2018; 9: 477
        • Herrick S.S.C.
        • Hallward L.
        • Duncan L.R.
        “This is just how I cope”: an inductive thematic analysis of eating disorder recovery content created and shared on TikTok using #EDrecovery.
        Int J Eat Disord. 2021; 54: 516-526
        • Fat M.J.
        • Sell E.
        • Barrowman N.
        • Doja A.
        Public perception of tourette syndrome on YouTube.
        J Child Neurol. 2012; 27: 1011-1016
        • Freeman R.D.
        • Zinner S.H.
        • Muller-Vahl K.R.
        • et al.
        Coprophenomena in tourette syndrome.
        Dev Med Child Neurol. 2009; 51: 218-227
        • Eddy C.M.
        • Cavanna A.E.
        On being your own worst enemy: an investigation of socially inappropriate symptoms in Tourette syndrome.
        J Psychiatr Res. 2013; 47: 1259-1263
        • Mainka T.
        • Balint B.
        • Govert F.
        • et al.
        The spectrum of involuntary vocalizations in humans: a video atlas.
        Mov Disord. 2019; 34: 1774-1791
        • Conte G.
        • Valente F.
        • Fioriello F.
        • Cardona F.
        Rage attacks in tourette syndrome and chronic tic disorder: a systematic review.
        Neurosci Biobehav Rev. 2020; 119: 21-36
        • Stafford M.
        • Cavanna A.E.
        Prevalence and clinical correlates of self-injurious behavior in Tourette syndrome.
        Neurosci Biobehav Rev. 2020; 113: 299-307
        • Cheung M.-Y.C.
        • Shahed J.
        • Jankovic J.
        Malignant tourette syndrome.
        Mov Disord. 2007; 22: 1743-1750
        • Szejko N.
        • Muller-Vahl K.R.
        Challenges in the diagnosis and assessment in patients with tourette syndrome and comorbid obsessive-compulsive disorder.
        Neuropsychiatr Dis Treat. 2021; 17: 1253-1266
        • Mathews C.A.
        • Waller J.
        • Glidden D.
        • et al.
        Self injurious behaviour in Tourette syndrome: correlates with impulsivity and impulse control.
        J Neurol Neurosurg Psychiatry. 2004; 75: 1149-1155
        • Kurvits L.
        • Mainka T.
        • Cavanna A.E.
        • Kühn A.A.
        • Ganos C.
        Aggression toward others misdiagnosed as primary tics.
        Mov Disord Clin Pract. 2021; 8: 769-771
        • Ganos C.
        • Munchau A.
        • Bhatia K.P.
        The semiology of tics, Tourette's, and their associations.
        Mov Disord Clin Pract. 2014; 1: 145-153
        • Leckman J.F.
        Phenomenology of tics and natural history of tic disorders.
        Brain Dev. 2003; 25: S24-S28
        • Leckman J.F.
        • Bloch M.H.
        • Scahill L.
        • King R.A.
        Tourette syndrome: the self under siege.
        J Child Neurol. 2006; 21: 642-649
        • Ganos C.
        • Bongert J.
        • Asmuss L.
        • Martino D.
        • Haggard P.
        • Münchau A.
        The somatotopy of tic inhibition: where and how much?.
        Mov Disord. 2015; 30: 1184-1189
        • Olvera C.
        • Stebbins G.T.
        • Goetz C.G.
        • Kompoliti K.
        TikTok tics: a pandemic within a pandemic.
        Mov Disord Clin Pract. 2021; 8: 1200-1205
        • Bartholomew R.E.
        • Wessely S.
        • Rubin G.J.
        Mass psychogenic illness and the social network: is it changing the pattern of outbreaks?.
        J R Soc Med. 2012; 105: 509-512
        • Pellicciari R.
        • Superbo M.
        • Gigante A.F.
        • Livrea P.
        • Defazio G.
        Disease modeling in functional movement disorders.
        Parkinsonism Relat Disord. 2014; 20: 1287-1289
        • Ghosh R.
        • Biswas U.
        • Roy D.
        • et al.
        De novo movement disorders and COVID-19: exploring the interface.
        Mov Disord Clin Pract. 2021; 8: 669-680
        • Woods D.W.
        Managing Tourette Syndrome: A Behavioral Intervention for Children and Adults: Therapist Guide.
        Oxford University Press, Oxford; New York2008
        • Hedderly T.
        • Heyman I.
        • Ganos C.
        • et al.
        Neurosymptoms.org functional tics factsheet [online].
        (Available at:)
        www.neurosymptoms.org
        Date accessed: July 30, 2021
        • Paszek J.
        • Pollok B.
        • Biermann-Ruben K.
        • et al.
        Is it a tic?--Twenty seconds to make a diagnosis.
        Mov Disord. 2010; 25: 1106-1108
        • van der Salm S.M.
        • de Haan R.J.
        • Cath D.C.
        • van Rootselaar A.F.
        • Tijssen M.A.
        The eye of the beholder: inter-rater agreement among experts on psychogenic jerky movement disorders.
        J Neurol Neurosurg Psychiatry. 2013; 84: 742-747
        • Kim D.D.
        • Kung C.S.
        • Perez D.L.
        Helping the public understand adverse events associated with COVID-19 vaccinations: lessons learned from functional neurological disorder.
        JAMA Neurol. 2021; 78: 789-790