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Table of Contents
REVIEW ARTICLES
Year : 2023  |  Volume : 6  |  Issue : 1  |  Page : 7-12

Geste antagoniste in dystonia: Demystifying the tricks


1 Department of Clinical Neurosciences, National Institute of Mental Health and Neurosciences, Hosur Road, Bengaluru, Karnataka, India; Department of Neurology, National Institute of Mental Health and Neurosciences, Hosur Road, Bengaluru, Karnataka, India
2 Department of Neurology, National Institute of Mental Health and Neurosciences, Hosur Road, Bengaluru, Karnataka, India

Date of Submission21-Oct-2022
Date of Decision02-Dec-2022
Date of Acceptance06-Feb-2023
Date of Web Publication28-Apr-2023

Correspondence Address:
Pramod K Pal
Department of Neurology, National Institute of Mental Health and Neurosciences (NIMHANS), Hosur Road, Bengaluru - 560029, Karnataka
India
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Source of Support: None, Conflict of Interest: None


DOI: 10.4103/aomd.aomd_51_22

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  Abstract 

Sensory tricks, also known as “geste antagoniste” or “alleviating maneuvers,” refer to specific maneuvers that temporarily improve dystonic postures; this is often considered to be a hallmark of primary dystonia. Although classically described to be simple activities such as a gentle touch, they can be complex and multisensory, including tactile, proprioceptive, visual, auditory, and thermal stimuli or even imaginary tricks. To date, there is no concrete concept to explain the mechanisms by which geste antagoniste alleviate dystonia. The suggested mechanisms imply an increase in intracortical facilitation in dystonia, and balance between facilitation and inhibition is restored by the geste. This narrative review aims to provide a brief overview of geste antagoniste, covering the historical aspects, types of geste, known mechanisms, and implications.

Keywords: Alleviating maneuvers, dystonic posture, geste antagoniste, history, implications, mechanism, review, types, sensory tricks


How to cite this article:
Prasad S, Holla VV, Kumar Sahoo L, Batra D, Stezin A, Mahale RR, Kamble NL, Yadav R, Pal PK. Geste antagoniste in dystonia: Demystifying the tricks. Ann Mov Disord 2023;6:7-12

How to cite this URL:
Prasad S, Holla VV, Kumar Sahoo L, Batra D, Stezin A, Mahale RR, Kamble NL, Yadav R, Pal PK. Geste antagoniste in dystonia: Demystifying the tricks. Ann Mov Disord [serial online] 2023 [cited 2023 May 28];6:7-12. Available from: https://www.aomd.in/text.asp?2023/6/1/7/375303




  Introduction Top


Sensory tricks, also known as “geste antagoniste” or “alleviating maneuvers,” are specific maneuvers that temporarily alleviate dystonic postures; this is often considered to be a hallmark of primary dystonia.[1] In most patients, these geste are often self-developed, serendipitous discoveries.[2] Of note, patients may not recall the actual onset of discovering the sensory trick. Although classically described to be simple activities such as a gentle touch, they can be complex and multisensory.[1] Dystonia tends to cause a marked reduction in the quality of life and often forces patients to identify coping strategies that work best for them.[3] Furthermore, the impact of the medications may be suboptimal with curative treatments being elusive, which further compels patients to adopt alternative strategies.

Despite the concept of geste antagoniste existing for over a century,[4] an aura of mystery still surrounds it. This may be attributable to various factors such as the growing heterogeneity of the types of stimuli, which may induce a geste, lack of specificity between the type of dystonia and the relevant stimuli, variability among patients, the transient nature of improvement, and most importantly, the lack of an underlying mechanism for these sensory tricks. This narrative review aims to provide a brief overview of geste antagoniste covering the historical aspects, types of geste, known mechanisms, and implications.


  Historical aspects of geste antagoniste Top


In 1894, Brissaud described seven patients with torticollis and reported a new sign, which he described as a “simple mannerism, childish behaviour, or pathological fake.”[5],[6] Minor stimuli in the form of touch, either with a body part or even supporting the head against a wall, led to alleviation of the dystonia. Although his descriptions were comprehensive and accurate, Brissaud considered torticollis to be a nonorganic disorder and the presence of these strange maneuvers compounded his beliefs. Following this, several reports emerged that reported the same phenomenon. In 1902, Meige and Fiendel, christened the phenomenon reported by Brissaud as “geste antagoniste efficace.” However, in their descriptions of this phenomenon, they further reinforced the psychogenic nature of torticollis and geste antagoniste. The concept of organicity was reintroduced in 1944 following the work of Ernst Herz[7] and established by Marsden between the 1970s and 1980s.[8] The term “sensory trick,” is the English counterpart of geste antagoniste. However, in 2014, Patel et al.[9] suggested “alleviating maneuver” as an alternative and more appropriate term in lieu of “sensory trick” as the latter suggests that a sensory input is mandatory, and more importantly, a trick implies a fake; therefore, it suggests its psychogenic nature.


  Types of geste antagoniste Top


Although Brissaud’s classical description was that of simple activities such as a gentle touch, geste can be complex and bizarre and involve the use of external objects.[1] The latter may often be mistaken to arise from a functional etiology. The type of external object utilized by a patient to produce a geste may often be surprising, and this highlights the serendipitous nature of discovering its presence.

As mentioned earlier, the term “sensory trick” is a misnomer. This is because sensory input is not always necessary nor is it always sufficient to improve the dystonia. In addition, geste may often be multisensory, including tactile, proprioceptive, visual, auditory, and thermal stimuli or even imaginary tricks. Based on these features, geste may be classified as typical or atypical. A typical or true geste is purely sensory and often requires only a gentle touch with no specific directionality to the touch.[1],[10] In contrast, atypical geste include tricks that are forceful, with the movements almost always antagonistic to the direction of the dystonia.[1] Motor tricks are a variant, where a voluntary movement is a critical component of the sensory trick. Reverse sensory tricks are an interesting phenomenon, where either sensory or motor stimuli can lead to worsening of the dystonia.[11]

It is imperative to know that the sensory input for a sensory trick is not limited to touch or proprioception [Table 1].
Table 1: Types of stimuli to induce geste antagoniste

Click here to view


  • Tactile or proprioceptive stimuli: This is usually the most effective and common stimuli that has been reported in multiple types of dystonia, ranging from focal dystonia to generalized dystonia.[1],[12] In addition to the simple act of touching a body part with a finger or hand, reports on the use of external objects to induce the geste in cervical dystonia, blepharospasm, oromandibular dystonia, generalized dystonia, etc. are of importance.[13],[14],[15],[16],[17],[18],[19],[20],[21],[22]


  • [Figure 1] and the supplementary video demonstrate the use of a range of objects utilized by our patients to produce a sensory trick. These objects were a cigarette or coin for oromandibular dystonia; a handkerchief for facial dystonia; and a water bottle, mug, or back brace for generalized dystonia.


  • Visual or auditory stimuli: For visual stimuli, cervical dystonia is a prime example of improvement being reported while looking in a mirror or fixating on a target.[23] The examples of auditory stimuli are intriguing. Laryngeal dystonia has been reported to improve with loud background noise,[24] and a remarkable improvement in generalized DYT1 dystonia was reported with piano playing.[25]


  • Thermal stimuli: Cooling of the dystonic region has been reported to improve dystonia in writer’s cramp[26] and embouchure dystonia.[27] Of note, heat was found to worsen the dystonia.


  • Imaginary stimuli: This may be the most contradictory type of stimuli to produce a “sensory” trick. Reduction in dystonia has been reported by imagining the actual sensory trick.[13],[28],[29] Cervical dystonia was shown to improve upon imagining a normal head position.[30],[31] Finally, imagining running in a manner antagonistic to the dystonic posture was reported to improve runner’s dystonia.[32]
  • Figure 1: Pictorial representation of innovative geste antagoniste

    Click here to view



      Mechanisms of geste antagoniste Top


    To date, there is no concrete concept to explain the mechanisms by which geste antagoniste alleviate dystonia. As mentioned earlier, the high extent of variability in stimuli that can induce a geste, lack of specificity of the stimuli between patients for the same kind of dystonia, topographic specificity, the temporary nature of improvement, etc. contribute to the lack of a unifying concept. It is likely that there may be varying mechanisms based on the type of stimuli and the underlying dystonia.

    Electromyographic recordings have been extensively used to study dystonia and geste antagoniste. Changes with sensory tricks may include reduction in recruitment amplitude and density and an increase in tonic muscle activation.[12],[14] The latter serves to counteract the dystonic movements. It is frequently reported that tactile contact is not necessary for a sensory trick, and evidence from a report by Wissel et al.[12] substantiated this finding. Tactile sensory tricks were found to have a three-phase temporal profile: (1) initiation of the trick to prior to tactile contact, (2) contact and posture—start to end of the tactile contact, and (3) removal of the tactile contact to the end of the movement associated with the trick. A reduction of electromyographic activity was observed in both phase 1 and 2. In addition, dampening of spindle-afferent traffic may play a role in some sensory tricks,[22] as evidenced by the reduction of dystonia by cooling.[26],[27]

    Blink reflex studies have suggested that sensory tricks may act similarly to a pre-pulse stimulus, causing an inhibition of dystonic movements over contraction.[33] In addition, they may lead to a reduction in the magnitude of reflex response to exteroceptive stimuli.[34] A recent study evaluated the contingent negative variation, a slow brain potential that can gauge neuronal activity during the premovement phase.[35] They observed that sensory tricks may affect the mechanisms related to movement preparation in the premotor and primary motor areas, suggesting that sensory tricks may normalize impaired motor preparation in dystonia. Another interesting study assessed the role of the position of the dystonic body part when applying the geste.[13] They reported that cortical modification of sensory motor integration may lead to a reduction of the dystonia. A sensory trick was found to be most effective when the body part is in a neutral or slightly overcorrected position rather than in the baseline dystonic position. A recent concept of “closing the loop” suggests that a benefit from the sensory trick requires a closed tactile circuit and modulation of the frontoparietal sensorimotor networks.[10] Another recent study evaluated the impact of geste on kinematics of dystonia and reported that geste not only improved dystonic muscle contractions but also improved the efficiency of voluntary movements.[36] This report is in concurrence with the contingent negative variation study by Shin et al.[35]

    An imaging-driven study evaluating sensory tricks using positron emission tomography and electromyography reported hypometabolism of the supplementary motor area. The authors suggested that sensory tricks led to perceptual changes and acted like an “arousal stimuli” to correct the nondystonic state.[37] Another observation of this study regarding the mechanism of visual stimuli is that visual information may act as a compensatory mechanism for faulty proprioception in dystonia by improving pathways between the occipital and parietal lobes.

    Finally, a possible mechanistic explanation provided by transcranial magnetic stimulation is that a sensory trick leads to normalization of the dystonic brain [Figure 2]. In patients with dystonia, a high facilitation to inhibition ratio that leads to excessive movement has been suggested, and the sensory input provided by the geste will lead to a reduction of the facilitation; therefore, it normalizes the ration and improves motor output.[1],[38],[39]
    Figure 2: Schematic representation of pathways involved in dystonia. Red lines indicate inhibition; green lines indicate facilitation

    Click here to view


    In summary, the suggested mechanisms imply an increase in intracortical facilitation in dystonia, and the balance between facilitation and inhibition is restored by the geste. This may occur by normalization of abnormal gating of the sensory input to motor circuits.[1],[33] Some of these effects may operate upstream of the motor output. This may explain multisensory or imaginary stimuli. A recent alternative hypothesis is the possibility of cervical dystonia occurring secondary to an unstable neural integrator in the brainstem with the geste acting as the rectifying effect.[40]


      Implications of geste antagoniste Top


    The presence of geste antagoniste has both diagnostic and therapeutic implications. It is usually associated with primary dystonia; however, it may be observed in secondary dystonia. In addition, the presence of a geste may aid in differentiating dystonia from other neurological conditions. For example, a sensory trick is a diagnostically relevant clinical sign of blepharospasm.[41] Although the presence of geste antagoniste often aids in diagnosing the organicity of the dystonia, uncommon reports have suggested the presence of a sensory trick in functional dystonia.[42],[43]

    It is pertinent to know that the duration of the disease or severity of dystonia has no bearing on the presence or efficacy of the sensory trick in most cases.[44] As observed in our cases [[Figure 1], Video 1 [Additional file 1]], the improvement may extend beyond the topographic area, where the geste was applied, with the extent of improvement exceeding expectations from a geste and occasionally exceeding the improvement offered by medication. Although the effectiveness of the above demonstrated geste may appear to be promising with remarkable therapeutic potential, geste by themselves are not able be the sole treatment modality. These tricks tend to lose efficacy over the course of the illness[14],[45 and in cases where highly effective, geste should be actively adjunctive to medical therapy. The presence of a geste is considered to be a positive predictive factor for responsiveness to botulinum toxin.[46] Therefore, the presence of a geste should be explored in all scenarios.

    Finally, although the geste may be beneficial, the object and associated maneuver may be harmful, and the patient should be cautioned with safer alternatives being provided. For example, there was a risk of addiction to smoking in our cases, and it was avoided by suggesting the use a straw, and the patient using the coin was cautioned about choking hazards.


      Conclusion Top


    In conclusion, considering the important role geste antagoniste can play in improving dystonia and the heterogeneity in the types of geste, patients should be encouraged to explore the possible existence of such strategies. Furthermore, such suggestions by patients, although unlikely, should be considered for possible validity and utility.

    Acknowledgement

    None.

    Author contribution

    SP wrote the draft of the manuscript. VVH, LKS, DB, AS, RRM contributed to collection of the cases. VVH, NK, RY, PKP critically reviewed the manuscript. All authors have approved the final version of the manuscript.

    Ethical compliance statement

    All patients provided informed written consent for video recording and publication.

    Financial support and sponsorship

    Nil.

    Conflicts of interest

    There are no conflicts of interest.



     
      References Top

    1.
    Ramos VFML, Karp BI, Hallett M Tricks in dystonia: Ordering the complexity. J Neurol Neurosurg Psychiatry 2014;85:987-93.  Back to cited text no. 1
        
    2.
    Ochudło S, Drzyzga K, Drzyzga LR, Opala G Various patterns of gestes antagonistes in cervical dystonia. Parkinsonism Relat Disord 2007;13:417-20.  Back to cited text no. 2
        
    3.
    Mulroy E, Ganos C, Latorre A, Terkelsen AJ, Balint B, Agarwal PA, et al. Self-concocted, curious and creative coping strategies in movement disorders. Parkinsonism Relat Disord 2021;83:140-3.  Back to cited text no. 3
        
    4.
    Poisson A, Krack P, Thobois S, Loiraud C, Serra G, Vial C, et al. History of the ‘geste antagoniste’sign in cervical dystonia. J Neurol 2012;259:1580-4.  Back to cited text no. 4
        
    5.
    Brissaud E Vingt-quatrième leçon. Tics et spasmes cloniques de la face. Leçons sur les maladies nerveuses: La Salpêtrière 1893;1894:502-20.  Back to cited text no. 5
        
    6.
    Broussolle E, Laurencin C, Bernard E, Thobois S, Danaila T, Krack P Early illustrations of geste antagoniste in cervical and generalized dystonia. Tremor Other Hyperkinetic Mov (NY) 2015;5:332.  Back to cited text no. 6
        
    7.
    Herz E Dystonia: I. Historical review; analysis of dystonic symptoms and physiologic mechanisms involved. Arch Neurol Psychiatry 1944;51:305-18.  Back to cited text no. 7
        
    8.
    Marsden CD The problem of adult-onset idiopathic torsion dystonia and other isolated dyskinesias in adult life (including blepharospasm, oromandibular dystonia, dystonic writer’s cramp, and torticollis, or axial dystonia). Adv Neurol 1976;14:259-76.  Back to cited text no. 8
        
    9.
    Patel N, Jankovic J, Hallett M Sensory aspects of movement disorders. Lancet Neurol 2014;13:100-12.  Back to cited text no. 9
        
    10.
    Frucht SJ “Closing the loop” in cervical dystonia: A new clinical phenomenon. Tremor Other Hyperkinetic Mov (NY) 2014;4: tre-04-283-6428-1.  Back to cited text no. 10
        
    11.
    Asmus F, von Coelln R, Boertlein A, Gasser T, Mueller J Reverse sensory geste in cervical dystonia. Mov Disord 2009;24:297-300.  Back to cited text no. 11
        
    12.
    Wissel J, Müller J, Ebersbach G, Poewe W Trick maneuvers in cervical dystonia: Investigation of movement-and touch-related changes in polymyographic activity. Mov Disord 1999;14:994-9.  Back to cited text no. 12
        
    13.
    Schramm A, Reiners K, Naumann M Complex mechanisms of sensory tricks in cervical dystonia. Mov Disord 2004;19:452-8.  Back to cited text no. 13
        
    14.
    Müller J, Wissel J, Masuhr F, Ebersbach G, Wenning G, Poewe W Clinical characteristics of the geste antagoniste in cervical dystonia. J Neurol 2001;248:478-82.  Back to cited text no. 14
        
    15.
    Bain PG, Liu X, Aziz TZ Increase in the tactile catchment area of a sensory trick for alleviating blepharospasm following pallidal DBS. Mov Disord 2009;24:624-6.  Back to cited text no. 15
        
    16.
    Lo SE, Gelb M, Frucht SJ Geste Antagonistes in Idiopathic Lower Cranial Dystonia. Wiley Online Library; 2007.  Back to cited text no. 16
        
    17.
    Frucht SJ, Fahn S, Greene PE, O’Brien C, Gelb M, Truong DD, et al. The natural history of embouchure dystonia. Mov Disord 2001;16:899-906.  Back to cited text no. 17
        
    18.
    Satoh M, Narita M, Tomimoto H Three cases of focal embouchure dystonia: Classifications and successful therapy using a dental splint. Eur Neurol 2011;66:85-90.  Back to cited text no. 18
        
    19.
    Erbguth F, Lange R Sensory trick effect in craniofacial dystonia as one of the possible impacts of wearing face masks during the COVID-19 pandemic. Neurol Res Pract 2021;3:24.  Back to cited text no. 19
        
    20.
    De Meyer M, Vereecke L, Bottenberg P, Jacquet W, Sims AB, Santens P Oral appliances in the treatment of oromandibular dystonia: A systematic review. Acta Neurol Belg 2020;120:831-6.  Back to cited text no. 20
        
    21.
    Khosravani S, Mahnan A, Yeh I, Aman JE, Watson PJ, Zhang Y, et al. Laryngeal vibration as a non-invasive neuromodulation therapy for spasmodic dysphonia. Sci Rep 2019;9:17955.  Back to cited text no. 21
        
    22.
    Kaji R, Rothwell JC, Katayama M, Ikeda T, Kubori T, Kohara N, et al. Tonic vibration reflex and muscle afferent block in writer’s cramp. Ann Neurol 1995;38:155-62.  Back to cited text no. 22
        
    23.
    Lee C-N, Eun M-Y, Kwon D-Y, Park MH, Park K-W “Visual sensory trick” in patient with cervical dystonia. Neurol Sci 2012;33:665-7.  Back to cited text no. 23
        
    24.
    Stojanovic M, Kostic V, Stankovic P, Sternic N Improvement in laryngeal dystonia with background noise. Mov Disord 1997;12:249-50.  Back to cited text no. 24
        
    25.
    Kojovic M, Pareés I, Sadnicka A, Kassavetis P, Rubio-Agusti I, Saifee TA, et al. The brighter side of music in dystonia. Arch Neurol 2012;69:917-19.  Back to cited text no. 25
        
    26.
    Pohl C, Happe J, Klockgether T Cooling improves the writing performance of patients with writer’s cramp. Mov Disord 2002;17:1341-4.  Back to cited text no. 26
        
    27.
    Kim JS, An JY, Lee KS, Kim HT Cooling can relieve the difficulty of playing the tuba in a patient with embouchure dystonia. Mov Disord 2007;22:2291-2.  Back to cited text no. 27
        
    28.
    LeDoux MS Dystonia: Phenomenology. Parkinsonism Relat Disord 2012;18(Suppl 1):S162-4.  Back to cited text no. 28
        
    29.
    Greene PE, Bressman S Exteroceptive and interoceptive stimuli in dystonia. Mov Disord 1998;13:549-51.  Back to cited text no. 29
        
    30.
    Lo SE, Frucht SJ Is Focal Task-Specific Dystonia Limited to the Hand and Face? Wiley Online Library; 2007.  Back to cited text no. 30
        
    31.
    Torres-Russotto D, Perlmutter JS Task-specific dystonias: A review. Ann N Y Acad Sci 2008;1142:179-99.  Back to cited text no. 31
        
    32.
    Suzuki K, Izawa N, Aiba S, Hashimoto K, Hirata K, Nakamura T Interoceptive sensory trick for runner’s dystonia. Mov Disord 2011;26:758-60.  Back to cited text no. 32
        
    33.
    Gómez-Wong E, Martí MJ, Tolosa E, Valls-Solé J Sensory modulation of the blink reflex in patients with blepharospasm. Arch Neurol 1998;55:1233-7.  Back to cited text no. 33
        
    34.
    Gómez-Wong E, Martı́ MJ, Cossu G, Fabregat N, Tolosa ES, Valls-Solé J The ‘geste antagonistique’ induces transient modulation of the blink reflex in human patients with blepharospasm. Neurosci Lett 1998;251:125-8.  Back to cited text no. 34
        
    35.
    Shin H-W, Cho HJ, Lee SW, Shitara H, Hallett M Sensory tricks in cervical dystonia correlate with enhanced brain activity during motor preparation. Parkinsonism Relat Disord 2021;84:135-8.  Back to cited text no. 35
        
    36.
    Newby R, Muhamed S, Alty J, Cosgrove J, Jamieson S, Smith S, et al. Geste antagoniste effects on motor performance in dystonia—A kinematic study. Mov Disord Clin Pract 2022;9:759-64.  Back to cited text no. 36
        
    37.
    Naumann M, Magyar-Lehmann S, Reiners K, Erbguth F, Leenders KL Sensory tricks in cervical dystonia: Perceptual dysbalance of parietal cortex modulates frontal motor programming. Ann Neurol 2000;47:322-8.  Back to cited text no. 37
        
    38.
    Amadio S, Houdayer E, Bianchi F, Tesfaghebriel Tekle H, Urban IP, Butera C, et al. Sensory tricks and brain excitability in cervical dystonia: A transcranial magnetic stimulation study. Mov Disord 2014;29:1185-8.  Back to cited text no. 38
        
    39.
    Tesfaghebriel H, Guerriero R, Urban I, Butera C, Amadio S, Del Carro U, et al P6. 6 Effect of sensory tricks on brain excitability in cervical dystonia: TMS study. Clin Neurophysiol 2011;122(Suppl 1):S85.  Back to cited text no. 39
        
    40.
    Shaikh AG, Zee DS, Crawford JD, Jinnah HA Cervical dystonia: A neural integrator disorder. Brain 2016;139:2590-9.  Back to cited text no. 40
        
    41.
    Defazio G, Jinnah HA, Berardelli A, Perlmutter JS, Berkmen GK, Berman BD, et al. Diagnostic criteria for blepharospasm: A multicenter international study. Parkinsonism Relat Disord 2021;91:109-14.  Back to cited text no. 41
        
    42.
    Lagrand TJ, Almuwais A, Lehn AC ‘Tricked’sensory trick: A geste antagoniste in functional dystonia. BMJ Case Rep 2022;15:e248779.  Back to cited text no. 42
        
    43.
    Munhoz RP, Lang AE Gestes antagonistes in psychogenic dystonia. Mov Disord 2004;19:331-2.  Back to cited text no. 43
        
    44.
    Pandey S, Soni G, Sarma N Sensory tricks in primary blepharospasm and idiopathic cervical dystonia. Neurol India 2017;65:532-6.  Back to cited text no. 44
        
    45.
    Martino D, Liuzzi D, Macerollo A, Aniello MS, Livrea P, Defazio G The phenomenology of the geste antagoniste in primary blepharospasm and cervical dystonia. Mov Disord 2010;25:407-12.  Back to cited text no. 45
        
    46.
    Filip P, Šumec R, Baláž M, Bareš M The clinical phenomenology and associations of trick maneuvers in cervical dystonia. J Neural Transm (Vienna) 2016;123:269-75.  Back to cited text no. 46
        


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