Posture, gait and self-disorders: An empirical study in individuals with schizophrenia.
early-onset
motor symptoms
negative symptoms
schizophrenia
self-disorders
Journal
Early intervention in psychiatry
ISSN: 1751-7893
Titre abrégé: Early Interv Psychiatry
Pays: Australia
ID NLM: 101320027
Informations de publication
Date de publication:
05 2023
05 2023
Historique:
revised:
17
05
2022
received:
22
12
2021
accepted:
05
07
2022
medline:
10
5
2023
pubmed:
9
5
2023
entrez:
8
5
2023
Statut:
ppublish
Résumé
In schizophrenia, subjectively perceived disruptions of the sense of the Self (also referred to as "self-disorders") seem to be intimately associated with a perturbation of the implicit awareness of one's own body. Indeed, an early impairment of the motor system, including posture and gait, is now considered a marker of schizophrenia neurodevelopmental substrate and appears more pronounced in early-onset schizophrenia. Therefore, the present study was aimed at: (1) investigating a possible relationship between self-disorders, symptom dimensions and postural and gait profile in schizophrenia; (2) identifying a specific motor profile in early-onset conditions. A total of 43 schizophrenia outpatients and 38 healthy controls underwent an exhaustive investigation of posture and gait pattern. The positive and negative syndrome scale (PANSS), the examination of anomalous self experience scale (EASE) and the abnormal involuntary movement scale (AIMS) were administered to the schizophrenia group. Subsequently, schizophrenia patients were divided into early and adult-onset subgroups and compared with respect to their motor profile. We found an association between specific postural patterns (impaired sway area), a general disruption of the gait cycle and subjective bodily experiences (concerning the loss of bodily integrity, cohesion and demarcation). Only motor parameters (increased sway area and gait cadence reduction) differentiated between early and adult-onset patients. The results of the present study hint at a link between motor impairment and self-disturbances in schizophrenia and candidate a specific motor profile as a possible marker of early-onset forms.
Types de publication
Journal Article
Langues
eng
Sous-ensembles de citation
IM
Pagination
447-461Informations de copyright
© 2022 John Wiley & Sons Australia, Ltd.
Références
American Psychiatric Association. (2013). Diagnostic and statistical manual of mental disorders (5th ed.). American Psychiatric Publishing.
Andreasen, N. C., Nopoulos, P., O'Leary, D. S., Miller, D. D., Wassink, T., & Flaum, M. (1999). Defining the phenotype of schizophrenia: Cognitive dysmetria and its neural mechanisms. Biological Psychiatry, 46(7), 908-920. https://doi.org/10.1016/s0006-3223(99)00152-3
Apthorp, D., Bolbecker, A. R., Bartolomeo, L. A., O'Donnell, B. F., & Hetrick, W. P. (2019). Postural sway abnormalities in schizotypal personality disorder. Schizophrenia Bulletin, 45(3), 512-521. https://doi.org/10.1093/schbul/sby141
Ardizzi, M., Ambrosecchia, M., Buratta, L., Ferri, F., Ferroni, F., Palladini, B., Volpe-Gaudelli, T., Peciccia, M., Mazzeschi, C., & Gallese, V. (2020). The motor roots of minimal self disorders in schizophrenia. Schizophrenia Research, 218, 302-303. https://doi.org/10.1016/j.schres.2020.03.007
Bachmann, S., Degen, C., Geider, F. J., & Schröder, J. (2014). Neurological soft signs in the clinical course of schizophrenia: Results of a meta-analysis. Frontiers in Psychiatry, 23, 185. https://doi.org/10.3389/fpsyt.2014.00185
Bernard, J. A., Dean, D. J., Kent, J. S., Orr, J. M., Pelletier-Baldelli, A., Lunsford-Avery, J. R., Gupta, T., & Mittal, V. A. (2014). Cerebellar networks in individuals at ultra high-risk of psychosis: Impact on postural sway and symptom severity. Human Brain Mapping, 35(8), 4064-4078. https://doi.org/10.1002/hbm.22458
Bleuler, E. (1911). Dementia praecox oder gruppe der schizophrenien. Deuticke.
Byrial, P., Nyboe, L., Thomsen, P. H., & Clausen, L. (2021). Motor impairments in early onset schizophrenia. Early Intervention in Psychiatry, 16(5), 481-491. https://doi.org/10.1111/eip.13185
Cermolacce, M., Naudin, J., & Parnas, J. (2007). The "minimal self" in psychopathology: Re-examining the self-disorders in the schizophrenia spectrum. Consciousness and Cognition, 16(3), 703-714. https://doi.org/10.1016/j.concog.2007.05.013
Ciaunica, A., Safron, A., & Delafield-Butt, J. (2021). Back to square one: The bodily roots of conscious experiences in early life. Neuroscience of Consciousness, 7(2), 1-10. https://doi.org/10.1093/nc/niab037
Clemmensen, L., Vernal, D. L., & Steinhausen, H. C. (2012). A systematic review of the long-term outcome of early onset schizophrenia. BMC Psychiatry, 19(12), 150. https://doi.org/10.1186/1471-244X-12-150
Costantini, M., Salone, A., Martinotti, G., Fiori, F., Fotia, F., Di Giannantonio, M., & Ferri, F. (2020). Body representations and basic symptoms in schizophrenia. Schizophrenia Research, 222, 267-273. https://doi.org/10.1016/j.schres.2020.05.038
Damiani, S., Donadeo, A., Bassetti, N., Salazar-de-Pablo, G., Guiot, C., Politi, P., & Fusar-Poli, P. (2022). Understanding source monitoring subtypes and their relation to psychosis: A systematic review and meta-analysis. Psychiatry and Clinical Neurosciences, 76(5), 162-171. https://doi.org/10.1111/pcn.13338
Dean, D. J., Kent, J. S., Bernard, J. A., Orr, J. M., Gupta, T., Pelletier-Baldelli, A., Carol, E. E., & Mittal, V. A. (2015). Increased postural sway predicts negative symptom progression in youth at ultrahigh risk for psychosis. Schizophrenia Research, 162(1-3), 86-89. https://doi.org/10.1016/j.schres.2014.12.039
Douaud, G., Mackay, C., Andersson, J., James, S., Quested, D., Ray, M. K., Connell, J., Roberts, N., Crow, T. J., Matthews, P. M., Smith, S., & James, A. (2009). Schizophrenia delays and alters maturation of the brain in adolescence. Brain, 132, 2437-2448.
Ebisch, S. J., Salone, A., Ferri, F., De Berardis, D., Romani, G. L., Ferro, F. M., & Gallese, V. (2013). Out of touch with reality? Social perception in first-episode schizophrenia. Social Cognitive and Affective Neuroscience, 8(4), 394-403. https://doi.org/10.1093/scan/nss012
Filatova, S., Koivumaa-Honkanen, H., Hirvonen, N., Freeman, A., Ivandic, I., Hurtig, T., Khandaker, G. M., Jones, P. B., Moilanen, K., & Miettunen, J. (2017). Early motor developmental milestones and schizophrenia: A systematic review and meta-analysis. Schizophrenia Research, 188, 13-20. https://doi.org/10.1016/j.schres.2017.01.029
First, M. B., Williams, J. B. W., Karg, R. S., & Spitzer, R. L. (2016). Structured clinical interview for DSM-5 disorders, clinician version (SCID-5-CV). American Psychiatric Association Publishing.
Fish, B., Marcus, J., Hans, S. L., Auerbach, J. G., & Purdue, S. (1992). Infants at risk for schizophrenia: Sequelae of a genetic neurointegrative defect. JAMA Psychiatry, 49, 221-235.
Frith, C. (2005). The neural basis of hallucinations and delusions. Comptes Rendus Biologie, 328, 169-175.
Fuchs, T., & Schlimme, J. E. (2009). Embodiment and psychopathology: A phenomenological perspective. Current Opinion in Psychiatry, 22(6), 570-575. https://doi.org/10.1097/YCO.0b013e3283318e5c
Fujino, H., & Imura, O. (2015). Postural sway and clinical characteristics in patients with psychotic disorders: A review. Psychiatric Quarterly, 86, 603-614.
Gallagher, S., eds. (2005) How the body shapes the mind. New York: Oxford University Press. https://doi.org/10.1093/0199271941.001.0001.
Gallese, V., & Ferri, F. (2014). Psychopathology of the bodily self and the brain: The case of schizophrenia. Psychopathology, 47(6), 357-364. https://doi.org/10.1159/000365638
Gogtay, N., Lu, A., Leow, A. D., Klunder, A. D., Lee, A. D., Chavez, A., Greenstein, D., Giedd, J. N., Toga, A. W., Rapoport, J. L., & Thompson, P. M. (2008). Three-dimensional brain growth abnormalities in childhood-onset schizophrenia visualized by using tensor-based morphometry. Proceedings of the National Academy of Science of the United States of America, 105, 15979-15984.
Gordt, K., Gerhardy, T., Najafi, B., & Schwenk, M. (2018). Effects of wearable sensor-based balance and gait training on balance, gait, and functional performance in healthy and patient populations: A systematic review and meta-analysis of randomized controlled trials. Gerontology, 64(1), 74-89. https://doi.org/10.1159/000481454
Henriksen, M. G., Raballo, A., & Nordgaard, J. (2021). Self-disorders and psychopathology: A systematic review. Lancet Psychiatry, 8(11), 1001-1012. https://doi.org/10.1016/S2215-0366(21)00097-3
Hertza, J., & Estes, B. (2011). Developmental dyspraxia and developmental coordination disorder. In A. S. Davis (Ed.), Handbook of pediatric neuropsychology (pp. 593-602). Springer.
Hirjak, D., Kubera, K. M., Thomann, P. A., & Wolf, R. C. (2018). Motor dysfunction as an intermediate phenotype across schizophrenia and other psychotic disorders: Progress and perspectives. Schizophrenia Research, 200, 26-34. https://doi.org/10.1016/j.schres.2017.10.007
Hirjak, D., Wolf, R. C., & Northoff, G. (2019). GABA and negative affect-catatonia as model of RDoC-based investigation in psychiatry. Schizophrenia Bulletin, 24, 1168-1169. https://doi.org/10.1093/schbul/sbz088
Ho, B. C., Mola, C., & Andreasen, N. C. (2004). Cerebellar dysfunction in neuroleptic naive schizophrenia patients: Clinical, cognitive, and neuroanatomic correlates of cerebellar neurologic signs. Biological Psychiatry, 55(12), 1146-1153. https://doi.org/10.1016/j.biopsych.2004.02.020
Jerrell, J. M., McIntyre, R. S., & Deroche, C. B. (2017). Diagnostic clusters associated with an early onset schizophrenia diagnosis among children and adolescents. Human Psychopharmacology, 32(2), e2589. https://doi.org/10.1002/hup.2589
Jeste, D.V., Glazer, W.M., Morgenstern, H., Pultz, J.A., Yeung, P.P. (1999). Rarity of tardive dyskinesia with quetiapine treatment of psychotic disorders in the elderly. Poster Presented at the 38th Annual Meeting of the American College of Neuropsychopharmacology. Acapulco, Mexico, December 12-16.
Kay, S. R., Fiszbein, A., & Opler, L. A. (1987). The positive and negative syndrome scale (PANSS) for schizophrenia. Schizophrenia Bulletin, 13, 261-276.
Kim, T., Lee, K. H., Oh, H., Lee, T. Y., Cho, K. I. K., Lee, J., & Kwon, J. S. (2018). Cerebellar structural abnormalities associated with cognitive function in patients with first-episode psychosis. Frontiers in Psychiatry, 3(9), 286. https://doi.org/10.3389/fpsyt.2018.00286
Klosterkötter, J., Schultze-Lutter, F., & Ruhrmann, S. (2008). Kraepelin and psychotic prodromal conditions. European Archives of Psychiatry and Clinical Neuroscience, 258(2), 74-84.4.
Koren, D., Lacoua, L., Rothschild-Yakar, L., & Parnas, J. (2016). Disturbances of the basic self and prodromal symptoms among young adolescents from the community: A pilot population-based study. Schizophrenia Bulletin, 42(5), 1216-1224. https://doi.org/10.1093/schbul/sbw010
Koren, D., Reznik, N., Adres, M., Scheyer, R., Apter, A., Steinberg, T., & Parnas, J. (2013). Disturbances of basic self and prodromal symptoms among non-psychotic help-seeking adolescents. Psychological Medicine, 43(7), 1365-1376. https://doi.org/10.1017/S0033291712002322
Koren, D., Tzivoni, Y., Schalit, L., Adres, M., Reznik, N., Apter, A., & Parnas, J. (2020). Basic self-disorders in adolescence predict schizophrenia spectrum disorders in young adulthood: A 7-year follow-up study among non-psychotic help-seeking adolescents. Schizophrenia Research, 216, 97-103. https://doi.org/10.1016/j.schres.2019.12.022
Kyrios, M., Nelson, B., Ahern, C., Fuchs, T., & Parnas, J. (2015). The self in psychopathology. Psychopathology, 48(5), 275-277. https://doi.org/10.1159/000438876
Lenzenweger, M. F., Maher, B. A., & Manschreck, T. C. (2005). Paul E. Meehl's influence on experimental psychopathology: Fruits of the nexus of schizotypy and schizophrenia, neurology, and methodology. Journal of Clinical Psychology, 61(10), 1295-1315. https://doi.org/10.1002/jclp.20183
Loch, A. A. (2019). Schizophrenia, not a psychotic disorder: Bleuler revisited. Frontiers in Psychiatry, 10(10), 328. https://doi.org/10.3389/fpsyt.2019.00328
Lord, S., Galna, B., & Rochester, L. (2013). Moving forward on gait measurement: Toward a more refined approach. Movement Disorders, 28(11), 1534-1543. https://doi.org/10.1002/mds.25545
Marchesi, C., Affaticati, A., Monici, A., De Panfilis, C., Ossola, P., & Tonna, M. (2014). Predictors of symptomatic remission in patients with first-episode schizophrenia: A 16years follow-up study. Comprehensive Psychiatry, 55(4), 778-784. https://doi.org/10.1016/j.comppsych.2013.12.011
Margari, F., Presicci, A., Petruzzelli, M. G., Ventura, P., Di Cuonzo, F., Palma, M., & Margari, L. (2008). Very early onset and greater vulnerability in schizophrenia: A clinical and neuroimaging study. Neuropsychiatric Disease and Treatment, 4(4), 825-830. https://doi.org/10.2147/ndt.s2484
Martin, L., Stein, K., Kubera, K., Troje, N. F., & Fuchs, T. (2022). Movement markers of schizophrenia: A detailed analysis of patients' gait patterns. European Archives of Psychiatry and Clinical Neuroscience. [Epub ahead of print]. https://doi.org/10.1007/s00406-022-01402-y
Nagymáté, G., Orlovits, Z., & Kiss, R. M. (2018). Reliability analysis of a sensitive and independent stabilometry parameter set. PLoS One, 13(4), e0195995. https://doi.org/10.1371/journal.pone.0195995
Nasrallah, H. A. (2005). Neurologic comorbidities in schizophrenia. Journal of Clinical Psychiatry, 66(6), 34-46.
Nelson, B., Whitford, T. J., Lavoie, S., & Sass, L. A. (2014). What are the neurocognitive correlates of basic self-disturbance in schizophrenia? Integrating phenomenology and neurocognition: Part 2 (aberrant salience). Schizophrenia Research, 152(1), 20-27. https://doi.org/10.1016/j.schres.2013.06.033
Nordgaard, J., Nilsson, L. S., Saebye, D., & Parnas, J. (2018). Self-disorders in schizophrenia-spectrum disorders: A 5-year follow-up study. European Archives of Psychiatry and Clinical Neuroscience, 268(7), 713-718. https://doi.org/10.1007/s00406-017-0837-3
Nordgaard, J., & Parnas, J. (2014). Self-disorders and the schizophrenia spectrum: A study of 100 first hospital admissions. Schizophrenia Bulletin, 40(6), 1300-1307. https://doi.org/10.1093/schbul/sbt239
Northoff, G., Hirjak, D., Wolf, R. C., Magioncalda, P., & Martino, M. (2021). All roads lead to the motor cortex: Psychomotor mechanisms and their biochemical modulation in psychiatric disorders. Molecular Psychiatry, 26(1), 92-102. https://doi.org/10.1038/s41380-020-0814-5
Park, S., & Baxter, T. (2022). Schizophrenia in the flesh: Revisiting schizophrenia as a disorder of the bodily self. Schizophrenia Research, 4: S0920-9964(21)00515-6, 242, 113-117. https://doi.org/10.1016/j.schres.2021.12.031
Parnas, J., & Handest, P. (2003). Phenomenology of anomalous self-experience in early schizophrenia. Comprehensive Psychiatry, 44(2), 121-134. https://doi.org/10.1053/comp.2003.50017
Parnas, J., & Henriksen, M. G. (2014). Disordered self in the schizophrenia spectrum: A clinical and research perspective. Harvard Review of Psychiatry, 22(5), 251-265. https://doi.org/10.1097/HRP.0000000000000040
Parnas, J., Møller, P., Kircher, T., Thalbitzer, J., Jansson, L., Handest, P., & Zahavi, D. (2005). EASE: Examination of anomalous self-experience. Psychopathology, 38(5), 236-258. https://doi.org/10.1159/000088441
Picard, H., Amado, I., Mouchet-Mages, S., Olie, J. P., & Krebs, M. O. (2007). The role of the cerebellum in schizophrenia: An update of clinical, cognitive, and functional evidences. Schizophrenia Bulletin, 34, 155-172.
Poletti, M., Gebhardt, E., Kvande, M. N., Ford, J., & Raballo, A. (2019). Motor impairment and developmental psychotic risk: Connecting the dots and narrowing the pathophysiological gap. Schizophrenia Bulletin, 45(3), 503-508. https://doi.org/10.1093/schbul/sby100
Poletti, M., Gebhardt, E., & Raballo, A. (2017). Corollary discharge, self-agency, and the neurodevelopment of the psychotic mind. JAMA Psychiatry, 74, 1169-1170.
Pontillo, M., Averna, R., Tata, M. C., Chieppa, F., Pucciarini, M. L., & Vicari, S. (2021). Neurodevelopmental trajectories and clinical profiles in a sample of children and adolescents with early- and very-early-onset schizophrenia. Frontiers in Psychiatry, 16(12), 662093. https://doi.org/10.3389/fpsyt.2021.662093
Presta, V., Paraboschi, F., Marsella, F., Lucarini, V., Galli, D., Mirandola, P., Banchini, A., Marchesi, C., Galuppo, L., Vitale, M., Tonna, M., & Gobbi, G. (2021). Posture and gait in the early course of schizophrenia. PLoS One, 16(1), e0245661. https://doi.org/10.1371/journal.pone.0245661
Putzhammer, A., Heindl, B., Broll, K., Pfeiff, L., Perfahl, M., & Hajak, G. (2004). Spatial and temporal parameters of gait disturbances in schizophrenic patients. Schizophrenia Research, 69(2-3), 159-166. https://doi.org/10.1016/s0920-9964(03)00090-2
Putzhammer, A., & Klein, H. E. (2006). Quantitative analysis of motor disturbances in schizophrenic patients. Dialogues in Clinical Neuroscience, 8(1), 123-130. https://doi.org/10.31887/DCNS.2006.8.1/aputzhammer
R Core Team. (2021). R: A language and environment for statistical computing. R Foundation for Statistical Computing URL https://www.R-project.org/
Raballo, A., Monducci, E., Ferrara, M., Fiori Nastro, P., Dario, C., & RODIN group. (2018). Developmental vulnerability to psychosis: Selective aggregation of basic self-disturbance in early onset schizophrenia. Schizophreina Research., 201, 367-372. https://doi.org/10.1016/j.schres.2018.05.012
Raballo, A., Poletti, M., Preti, A., & Parnas, J. (2021). The self in the Spectrum: A meta-analysis of the evidence linking basic self-disorders and schizophrenia. Schizophrenia Bulletin, 47(4), 1007-1017. https://doi.org/10.1093/schbul/sbaa201
Rapoport, J., Chavez, A., Greenstein, D., Addington, A., & Gogtay, N. (2009). Autism spectrum disorders and childhood-onset schizophrenia: Clinical and biological contributions to a relation revisited. Journal of the American Academy of Childhood and Adolescent Psychiatry, 48(1), 10-18. https://doi.org/10.1097/CHI.0b013e31818b1c63
Rochat, P., & Striano, T. (2000). Perceived self in infancy. Infant Behavior and Development, 23(3-4), 513-530.
Sanders, R. D., & Gillig, P. M. (2010). Gait and its assessment in psychiatry. Psychiatry (Edgmont), 7(7), 38-43.
Sass, L. A., & Parnas, J. (2003). Schizophrenia, consciousness, and the self. Schizophrenia Bulletin, 29(3), 427-444. https://doi.org/10.1093/oxfordjournals.schbul.a007017
Schiffman, J., Mittal, V., Kline, E., Mortensen, E. L., Michelsen, N., Ekstrøm, M., Millman, Z. B., Mednick, S. A., & Sørensen, H. J. (2015). Childhood dyspraxia predicts adult-onset nonaffective-psychosis-spectrum disorder. Development and Psychopathology, 27(4 Pt 1), 1323-1330. https://doi.org/10.1017/S0954579414001436
Schmahmann J.D. (1998). Dysmetria of thought: Clinical consequences of cerebellar dysfunction on cognition and affect. Trends in Cognitive Sciences, 1, 2(9):362-71. https://doi.org/10.1016/s1364-6613(98)01218-2
Schneider, K. (1959). Clinical psychopathology. Grune and Stratton.
Schröder, J., & Toro, P. (2020). Neurological soft signs predict outcomes in schizophrenia. Nature Reviews. Neurology, 16(12), 659-660. https://doi.org/10.1038/s41582-020-0403-x
Scoppa, F., Capra, R., Gallamini, M., & Shiffer, R. (2013). Clinical stabilometry standardization: Basic definitions-Acquisition interval-Sampling frequency. Gait & Posture, 37(2), 290-292. https://doi.org/10.1016/j.gaitpost.2012.07.009
Sestito, M., Raballo, A., Umiltà, M. A., Leuci, E., Tonna, M., Fortunati, R., De Paola, G., Amore, M., Maggini, C., & Gallese, V. (2015). Mirroring the self: Testing neurophysiological correlates of disturbed self-experience in schizophrenia spectrum. Psychopathology, 48(3), 184-191. https://doi.org/10.1159/000380884
Stanghellini, G. (2009). Embodiment and schizophrenia. World Psychiatry, 8(1), 56-59. https://doi.org/10.1002/j.2051-5545.2009.tb00212.x
Stensdotter, A. K., Lorås, H. W., Fløvig, J. C., & Djupsjöbacka, M. (2013). Postural control in quiet standing in patients with psychotic disorders. Gait & Posture, 38(4), 918-922. https://doi.org/10.1016/j.gaitpost.2013.04.017
Taylor, M. A., Shorter, E., Vaidya, N. A., & Fink, M. (2010). The failure of the schizophrenia concept and the argument for its replacement by hebephrenia: Applying the medical model for disease recognition. Acta Psychiatrica Scandinavica, 122(3), 173-183. https://doi.org/10.1111/j.1600-0447.2010.01589.x
Teng, Y. L., Chen, C. L., Lou, S. Z., Wang, W. T., Wu, J. Y., Ma, H. I., & Chen, V. C. (2016). Postural stability of patients with schizophrenia during challenging sensory conditions: Implication of sensory integration for postural control. PLoS One, 11(6), e0158219. https://doi.org/10.1371/journal.pone.0158219
Tonna, M., Ossola, P., Marchesi, C., Bettini, E., Lasalvia, A., Bonetto, C., Lenzi, J., Rucci, P., Iozzino, L., Cellini, M., Comacchio, C., Cristofalo, D., D'Agostino, A., de Girolamo, G., De Santi, K., Ghigi, D., Leuci, E., Miceli, M., Meneghelli, A., … GET UP Group. (2019). Dimensional structure of first episode psychosis. Early Intervention in Psychiatry, 13(6), 1431-1438. https://doi.org/10.1111/eip.12789
van der Gaag, M., Hoffman, T., Remijsen, M., Hijman, R., de Haan, L., van Meijel, B., van Harten, P. N., Valmaggia, L., de Hert, M., Cuijpers, A., & Wiersma, D. (2006). The five factor model of the positive and negative syndrome scale II: A ten-fold cross-validation of a revised model. Schizophrenia Research, 85, 280-287.
Varambally, S., Venkatasubramanian, G., Thirthalli, J., Janakiramaiah, N., & Gangadhar, B. N. (2006). Cerebellar and other neurological soft signs in antipsychotic-naïve schizophrenia. Acta Psychiatrica Scandinavica, 114(5), 352-356. https://doi.org/10.1111/j.1600-0447.2006.00837.x
Walker, E. F., Savoie, T., & Davis, D. (1994). Neuromotor precursors of schizophrenia. Schizophrenia Bulletin, 20(3), 441-451
Walther, S., & Strik, W. (2012). Motor symptoms and schizophrenia. Neuropsychobiology, 66(2), 77-92. https://doi.org/10.1159/000339456
Wickham, H. (2016). ggplot2: Elegant graphics for data analysis. Springer-Verlag.