The Influence of Videography in the Foundation and Future of Movement Disorders

Abstract

Background

The diagnosis of movement disorders relies on identifying the salient phenomenology during clinical examination. Besides a thorough in‐person examination, the clinician may rely on video recording, particularly in cases of transient, fluctuating, or paroxysmal movement disorders. As such, this subspecialty has been profoundly influenced by the advent of and access to film, video, and digital documentation.

Objective

The aim was to review the historical development of video technology in the field of movement disorders, tracing its origins from early observational methods to its modern‐day applications in telemedicine, clinical research, and neurology education.

Methods

We conducted interviews with 10 experts in movement disorders, many of whom actively played a role in formalizing movement disorders as a clinical discipline.

Results

Our understanding of movement disorders was greatly advanced by the adoption of film at first and video later. The growing relative ease of access to videos allowed easy clinical use in the clinic and its display during video rounds and conferences. A session at the American Academy of Neurology led by David Marsden and Stanley Fahn played a particularly pivotal role in formalizing phenomenology and establishing video as a tool.

Conclusions

The use of patient recordings paralleled the growth of movement disorders as a field as they played a foundational role in the description of phenomenology, formulation of rating scales, and the education of neurologists. The potential of video recordings continues to be realized, most recently through telemedicine and the adoption of machine learning algorithms in research.

Movement disorders encompass a wide range of neurological conditions characterized by abnormal, involuntary, or semivoluntary, movements. Some of these disorders may take on fluctuating, sporadic, or paroxysmal patterns. Moreover, many movement disorders are rare, which historically hindered the diagnosis and formation of consensus definitions. This lack of consistency in description and documentation contributed to the proliferation of redundant and vaguely characterized entities (eg, St. Vitus chorea and Sydenham's chorea, the electric chorea of Dubini, paramyoclonus multiplex). ¹ , ² , ³ Patient recordings were first carried out on film reels, some of which date back to the first decade of the 20th century. ⁴ Over time, film was replaced by the lower‐quality but more practical formats (eg, magnetic tapes, video cassettes, Video Home System ‐ VHS, magnetic tapes), and more recently digital formats (eg, MPEG2, MPEG4). ⁵ , ⁶ The possibility of collecting footage of both common and uncommon manifestations ushered in a new era for neurology and movement disorders. Abnormal movements are difficult to describe with verbal and written language (even today) and were even more challenging to describe before consensus criteria and phenomenological terms were established. ⁷ Video recordings, on the contrary, preserve the full complexity of abnormal movements, complementing our written and oral descriptions, and offer an opportunity to retrospectively refine clinical diagnosis. ⁷ , ⁸ Additionally, some centers have separate rooms dedicated to video recording where the video is captured after the visit. This is an additional opportunity to revisit details about the patient's history and capture additional movements not observed during the visit.

Currently, video plays a central role for movement disorder specialists in diagnosing and monitoring patients, and educating trainees and colleagues, and in conferences. Our article explores the historical milestones of the use of video technology in movement disorders, from its inception in the early 20th century to the cutting‐edge tools of the present day. Although several articles have explored the early years of filmography in neurology and movement disorders, to the best of our knowledge, this is the first account describing the evolution of film, video, and digital recordings within movement disorders, bridging the older technology to the use of video in current times.

Patients and Methods

We conducted a series of interviews with movement disorders experts with expertise in the history of movement disorders and the use of film and video in this field. Dr. Stanley Fahn was interviewed via phone call by the authors; Dr. Anthony Lang was interviewed via teleconferencing software (Zoom); Drs. Christopher Goetz, Mark Hallett, and Caroline Tanner were interviewed in‐person; and Drs. Steven Frucht, Joseph Jankovic, Andrew Lees, Edison Miyawaki, and Michael Okun were interviewed via e‐mail.

Additionally, we searched PubMed using the following key words: (1) “movement disorders” AND “video,” (2) “movement disorders” AND “film,” (3) “neurology” AND “video,” and (4) “neurology” AND “film.” Further searches were performed through the American Academy of Neurology (AAN) Oral History Project and Movement Disorders Society (MDS) Oral History Project.

Early Observational Techniques in Movement Disorders (20th Century)

Before the advent of film and video, the assessment of movement disorders was limited to in‐person examinations and “phenomenology rounds,” where senior neurologists would demonstrate their clinical examination skills in front of a large group of clinicians. Presenting a patient in front of a group of clinicians has high educational value and stems directly from Charcot's now‐famous Lecons du Mardi (Tuesday lessons). ⁹ Education and exposure to movement disorder phenomenology occurred exclusively in person; otherwise, clinicians had to rely on written descriptions in the literature. In the case of paroxysmal or fluctuating movement disorders, clinicians frequently depended on descriptions from patients and family members, as there was no way to record the movements.

From the early 20th century onward, film had a seismic impact on society, the advent of which closely involved neurologists. It was a study of gait that motivated the creation of film. In fact, Eadward Muybridge, a photographer, developed the primordial filming equipment to settle Mr. Leland Stanford's bet around his horse's gallop in 1887. ¹⁰ In this bet, the magnate Stanford made a wager that horses lifted all 4 hooves off the ground simultaneously during the gallop. Muybridge set up a series of cameras along a racetrack in Stanford's farm, each triggered by the horse as it passed. With this, Muybridge proved that there is indeed a moment when all 4 hooves are off the ground and effectively produced the moving picture. With the support of the University of Pennsylvania, Muybridge transitioned his interest to the photography of gait in humans. His collaboration with the physician Francis Dercum resulted in 29 plates representing a variety of abnormal gaits, ataxia, spasticity, and nonepileptic seizures (“hystero‐epilepsy”). ¹¹ Neurologists were directly involved in the early growth of motion pictures, realizing the potential to capture disorders of movement. By the turn of the 20th century, several neurologists had adopted the use of film recordings across Europe, including Albert Londe and Paul Richer in Paris, Gheorghe Marinescu in Romania, and Arthur Van Gehuchten in Belgium. These included still photography, time‐lapse sequences, and eventually moving pictures. ¹² , ¹³ , ¹⁴ , ¹⁵

Later, the practice spread to England where Kinnier Wilson began filming patients with movement disorders. Wilson's endeavors appear to have been enabled by his friendship with film legend Charlie Chaplin. ¹⁶ Some of Wilson's footage survives today and includes depictions of Parkinson's disease and postencephalitic parkinsonism, hemiballismus, Huntington's disease, and Sydenham's chorea. ¹⁶ Dr. Derek Denny Brown at the Boston City Hospital also built an extensive catalog of film reels capturing patients and animal experiments with basal ganglia lesions. ¹⁷ Shortly thereafter, clinicians such as Philip Goodhart from Montefiore Hospital in New York City, J.D. Reichard from New York University, and James Purdon Martin from National Hospital, Queen Square, compiled film catalogs documenting conditions like encephalitis lethargica. ¹⁸ Although their efforts were a testament to the role of neurology in the early development of filmography, the production of film reels presented several challenges. These included the high costs of the cameras, the need for a dedicated studio, the limited run time, and the bulkiness of the reels and the cameras alike. ¹⁶

The Introduction of Video in Clinical Practice (1960s–1970s)

Given the potential of film recordings to supplement the exam of patients with disorders of movement, it should come as no surprise that film and video recordings greatly influenced and enabled the foundation of the subspecialty of movement disorders within neurology. Dr. Stanley Fahn was one of the founders of this field alongside Dr. David Marsden (Fig. 1: Drs. Fahn and Marsden sitting alongside Dr. Jankovic in the middle). Dr. Fahn directed the Division of Movement Disorders at Columbia University, which was founded in 1973. He had started using 8‐mm silent films during his time at the University of Pennsylvania at the end of the 1960s. ⁷ , ¹⁹ He continued this practice once he moved to Columbia University and initiated the practice of showing the films as a tool for peer education. ⁷ Initially, he would host colleagues, including important figures like Drs. Linda Lewis and Oliver Sacks, in his own home during after‐hours sessions. After a hearty meal of salad and homemade chili, they would communally view videos of patients with movement disorders, such as the now‐famous films of patients with postencephalitic parkinsonism from the Beth Abraham Hospital. ²⁰ , ²¹ Understanding the educational value of these communal viewings, Dr. Fahn founded the Basal Ganglia Club of Greater New York in 1975, which convened regularly at New York campuses at 4:00 p.m. on a monthly basis. ⁷ , ²² , ²³ The rotating host institution would be responsible for providing the recordings. With the transition from film to video and the increased ease of recording, viewing videos more regularly was a possibility. A similar initiative was led by Drs. David Marsden and Andrew Lees in the United Kingdom, where video also played a central role during their meetings. ²⁴ This came to be the “Basal Ganglia Club,” initiated as a collaboration between the Institute of Psychiatry and the Queens Square campus in 1982. ²⁴

FIG. 1.

Drs. Fahn, Jankovic, and Marsden. Left to right: Drs. Fahn, Jankovic, and Marsden at the first Aspen Course in 1991 (image courtesy of Dr. Jankovic).

Drs. Fahn and Marsden eventually united their efforts and brought this presentation format to the American Academy of Neurology Annual Meeting (AANAM) in a popular evening course titled “Unusual Movement Disorders,” which was run by both from 1981 to 1998, until Dr. Marsden's passing. ²⁴ This open forum allowed for an interactive exchange of ideas and diagnoses based on the films shown. Lively discussion around phenomenology laid the groundwork for phenomenological definitions and formal classifications within movement disorders, serving as the foundation for the field. The sessions, in highlighting the variability in the use of descriptive terms among clinicians and the need for a unified set of definitions, became a place where education in the fundamentals of movement disorders phenomenology could be debated and revised. ²⁵ , ²⁶ Dr. Marsden was particularly fond of asking the audience to vote on their opinions about the phenomenology and the diagnosis, which was a way to foster participant engagement and to gauge their strength, weaknesses, and areas in need of education. ²⁶ These sessions were extremely successful and grew year to year. The number of attendees reached over 100; the conference would be preceded by a dinner and be a festive event. In spite of being slotted from 7:00 to 10:00 p.m., it would run into the “wee hours of the morning.” ²⁰ As the popularity of the course grew, the course had to be split into 2 separate sessions, which would be held at the start of the meeting and at the end. The audience would also be allowed to submit their own videos, with more senior members first and fellows later. Many trainees look back fondly on this course as a core basis of their movement disorders education, as the course illustrated the perennial nature of movement disorders description and revision, the lively and informative disagreement between top experts, and the integration of novel and rare disorders into common awareness.

The Video Boom, Archiving, and Scales (1960s–2000s)

The shift from film reel to video formats (eg, video cassettes, magnetic tapes) resulted in a decrease in the quality of the recordings due to the technical compression of video. ²³ Video recordings evolved rapidly over the years, starting with commercially available film in the 1960s (8 mm and Super8 mm), followed by VHS and Betamax in the 1970s. These videotapes underwent gradual miniaturization in the 1980s and 1990s with formats such as VHS‐C, MiniDV, and Hi8. ⁵ With the transition from heavy VHS cameras to lighter VHS‐C cameras, these devices became more portable. ²⁷ This enabled clinicians and fellows to routinely record patients, which subsequently accelerated the universalization of movement disorders nosology and a common terminology. ²⁸ In parallel, the influence of the AANAM course and of Drs. Marsden's and Fahn's phenomenological methods created a community of clinicians interested in movement disorders. As a result, a dedicated society the Movement Disorder Society (MODIS) was founded in 1985 with the intent to found a journal, the Movement Disorders journal. ²⁵ , ²⁹ From its inception, video was planned as a key part of this publication, which featured case reports with associated videos. These were initially distributed periodically to all subscribers in VHS format, with later conversion to CD format, followed by a digital library encompassing all past publications. MODIS would later merge with another short‐lived organization, the International Medical Society of Motor Disturbances, to form the Movement Disorder Society (MDS) in 1992, later renamed the International Parkinson and Movement Disorder Society.

The practice of videotaping patients spread widely in the 1970s onward, and more effort was devoted to optimizing video recording settings, dedicating specific examination rooms with standardized lighting and contrast for consistent filming. For instance, Drs. Christopher Goetz, Caroline Tanner, and Harold Klawans at Rush University started videotaping patients in an adapted conference room. ²⁶ , ³⁰ To optimize contrast, white photo‐grade paper would be hung as backdrop. ³⁰ Over time, the conference room was replaced by a dedicated video examination room, with optimized lighting, contrast, and sound. The walls were famously painted blue as it allowed for optimal contrast with the patient. ²⁶ Meanwhile, a similar story was unfolding in the newly founded Parkinson's Disease Center and Movement Disorders Clinic (PDCMDC) at Baylor College of Medicine where Dr. Joseph Jankovic built the first “video‐suite” in the country. When he became the founder and director of the PDCMDC in 1977, he designated a “space near the clinic […] dedicated to filming.” ³¹ The studio would later be expanded when the PDCMDC moved from the Neurosensory Center to Smith Tower and finally to McNair Campus, at the heart of the world's largest medical center. Blue walls would also be used here, and the rooms would be equipped with state‐of‐the‐art lighting and sound control ³¹ (Fig. 2: PDCMDC video room and studio, credit: Dr. Jankovic).

FIG. 2.

PDCMDC (Parkinson's Disease Center and Movement Disorders Clinic) video room and studio. Video room at PDCMDC at Baylor College of Medicine.

Videotaping subsequently allowed for the establishment of scales for specific disorders, including Parkinson disease (Unified Parkinson's Disease Rating Scale [UPDRS]), Huntington's disease (Unified Huntington's Disease Rating Scale), and dyskinesias. ³² , ³³ , ³⁴ Video played a key role in validating these scales, optimizing inter‐rater reliability through independent rating and providing standardized education for future raters (eg, researchers, research coordinators, and fellows). ³⁵ , ³⁶ Today, these scales are widely used for both clinical and research purposes. For example, the UPDRS certification process uses training videos with instructions to ensure consistent assessment of motor symptoms, allowing high inter‐rater reliability and validity. ³⁶ This consistency plays a fundamental role in research because these scales are frequently employed as outcome measures. ³⁰ Additionally, clinical trials will record patient videos to allow independent and asynchronous review and scale scoring, all while preserving reliability and improving standardization. ³⁴ , ³⁷ This also allows for remote rating from expert raters and expands the access of patients to clinical trials. ³⁸ , ³⁹ , ⁴⁰

Alongside scales, experts recognized the need to standardize recording technique. Multiple reviews and a dedicated book by Drs. Brandon Barton and Deborah Hall provide tips and standards for videotaping patients, which adapted the long‐standing videotaping protocols Rush University already used in obtaining thousands of patient videos. ⁸ , ⁴¹ , ⁴² , ⁴³ , ⁴⁴ The standards for recording included (1) ideal lighting, (2) ideal camera setup (eg, distance from the patient, using a tripod to stabilize the camera), (3) recording technique (eg, having an assistant carry out the recording, avoiding sudden movements), (4) using specific shooting distances (eg, close‐up shots for eye movements, whole‐body shots to examine posture and movement), and (5) ensuring the quality of recording and compression (Fig. 3: Rush University Studio, credit: Dr. Brandon Barton). ⁴⁵ Additionally, written consent should be obtained from the patients and stored in a secure database. This allowed nonmedically trained staff members to rapidly learn the skills to accurately perform patient recordings, freeing up the physicians' time to do the clinical work independently of videotaping. Specific protocols could be tailored to determine all types of movement disorders, with separate protocols designated for tremor syndromes, Parkinson's disease, dystonia, and so forth. ²⁸ , ⁴³ , ⁴⁴

FIG. 3.

Rush University video room and studio. Video room at Rush University where patients would be filmed by the movement disorders team.

As video recording developed, so did the need for editing and archiving. Editing requirements changed rapidly over time. For example, Super8 film had to be edited by physically cutting and taping or gluing the films on an editing table. Video could be edited much more easily but still required dedicated equipment. To address this, Dr. Jankovic and his wife Cathy initially established an editing suite in their home for these purposes. Cathy Jankovic was the editor and video library manager (Fig. 4: Cathy Jankovic editing in their home video editing room, credit: Dr. Jankovic). Eventually, the center acquired the first nonlinear editing system in Houston, which simplified this processing step. Eventually, all analog videos since 1977 were digitized. Dr. Jankovic's video library now contains over 35,000 videos carefully cataloged according to patient diagnoses. This video library now serves as a rich resource for education and publishing endeavors (Fig. 5: PDCMDC editing room used by the fellows to prepare cases for weekly video rounds, credit: Dr. Jankovic). Nowadays, digital recordings can be easily edited using the software on the camcorder (eg, the editing program within a smartphone), the software on a computer system (eg, iMovie, Windows Movie Maker), or a separate software. ⁸

FIG. 4.

Photograph of Cathy Jankovic while editing. Cathy Jankovic has served as an editor and video library manager of the Parkinson's Disease Center and Movement Disorders Clinic (PDCMDC) at Baylor College of Medicine.

FIG. 5.

PDCMDC (Parkinson's Disease Center and Movement Disorders Clinic) editing room. The PDCMDC editing room is used by the fellows to prepare cases for the weekly video rounds at Baylor Medical Center.

Archiving needs also changed drastically. At first, physical space had to be secured to store film reels or videotapes. Although the volume of recordings was initially small enough to be housed in a conference room, later dedicated storage had to be secured. With the transition to digital format, the space requirements decreased because archiving was achieved through increasingly small physical formats from CD‐ROMs, to DVDs, and, finally, to password‐protected external or even internal hard drives. ²⁷ The same transition from video to digital also resulted in a potential loss of vital recordings, which centers like Baylor University and Rush University addressed by converting tapes to fully digital formats. ²⁶ , ³¹

On the contrary, the digital age resulted in a greatly expanding number of recordings, which has made meticulous labeling and cataloging of the digital files paramount. The current emphasis on cataloging is also reflected by the difficulty in finding early‐20th‐century films because cataloging was often not systematic with a few exceptions (eg, Denny Brown's collection). ¹⁷ Further, while cataloging in the age of videotapes followed simple rules, for example, writing patient information on the back of the tape (date of the exam, name, medical record number, etc.), the digital age relies on file labeling and storage within a database.

Video as a Tool for Education

From the early days of the AANAM's “Unusual Movement Disorders” course, video has been recognized as a powerful tool for educating neurologists. Because of its educational potential, Drs. Goetz, Tanner, and Klawans developed 2 published videotape collections on common movement disorders (Raven Press), anchored in video material. ³⁰ Since then, video recordings of patients have become a vital part of both movement disorder conferences and medical education. Today, medical students are exposed to videos of patients with movement disorders during lectures, through educational modules, and even during their exams. This allows them to become actively familiar with phenomenology from the early stages of their training. ⁴⁶ , ⁴⁷

Another key aspect of video as a tool for education is the tradition of the video rounds, where movement disorder specialists regularly convene to discuss challenging cases. A pioneering effort was Dr. Fahn's who established early‐morning weekly video rounds with fellows. ⁷ During these rounds, fellows presented their videos from the week. To ensure this, Dr. Fahn encouraged the trainees to carry their cameras and camera bags around the clinic and hospital, videotaping all new patients. This form of video rounds has now become commonplace across multiple campuses where fellows are taught how to perform video recordings, are encouraged to routinely provide footage for video rounds, and are assessed and educated on their ability to analyze a videotaped exam. This provides an opportunity to learn the nuances of analyzing videos and patients, demonstrate their ability to accurately capture patient exams, and observe how experts discuss and debate challenging movement disorders. Video rounds also convey the importance of polite disagreement. Due to the frequency of disagreeing opinions, the importance of polite disagreement comes from the early days when Drs. Fahn, Marsden, and other experts from around the world would discuss and debate phenomenology, diagnosis, and etiology in front of the AANAM audience.

As mentioned earlier, video is also a key component of academic publication, beginning with the Movement Disorders journal (Figs. [Link], [Link]). These articles helped readers become familiar with rare, paroxysmal, and novel presentations. Similarly, textbooks frequently use video as an educational tool. One early example is the video compilation Common Movement Disorders: A Video Presentation by Klawans et al. ⁴⁸ Online portals now feature videos of patient exams for the education of trainees; a few examples include the Continuum journal online portal, the MDS webpage, and the Neurology Journal's Teaching Video NeuroImages. ⁴⁹ , ⁵⁰ , ⁵¹ There is a growing number of textbooks with accompanying video samples attached as a CD or DVD or accessible online at the publisher's website, including the Encyclopedia of Movement Disorders and the Principles and Practice of Movement Disorders. ⁵² , ⁵³

Finally, video was adopted by the International Congress of the Movement Disorders Society as a form of education. Following the tradition of the AANAM course led by Drs. Fahn and Marsden, the annual congress introduced a video competition that evolved from “Video Olympics” to “Video Games” and most recently, to “Video Challenge.” ²⁵ Dr. Anthony Lang and the late Dr. Kapil Sethi were responsible for the design and leadership of this event, which started in 2007 during Dr. Lang's tenure as the president of the MDS. He was inspired by a similar event, which was held by the French Neurological Society during its annual meeting in Paris. In this competition, a panel of experts are tasked with describing and diagnosing the complex clinical presentations shown on video. The Video Challenge has been held annually since 2007 and is one of the most highly attended of the International Congress. The session combines education, clinical reasoning, and debate with video recordings. ⁵⁴

The Rise of Digital Video and the Telemedicine Revolution (2000s–Present)

The transition from analog to digital video in the 2000s allowed for easier storage, higher quality, and improved accessibility of the recordings. Digital video also allowed for much longer videos to be stored within the same physical medium (eg, CD‐ROM and DVDs) or digital file (eg, direct recording on smartphone). Digital video also offered the unique opportunity of random access, that is, jumping directly to a desired portion of the recording. ⁸ Digital video technology also allowed for the application of improved analysis techniques, which further reveal the complexities of phenomenology. For instance, digital video can be manipulated easily (eg, slow motion, zoom, frame‐by‐frame analysis), which can supplement the analysis of the exam.

Researchers and clinicians could now archive vast collections of video data, while digital analysis tools enabled a more detailed study of movements. The videos could also be shared easily among clinicians and edited on the same software used for recording. For journals and readers, this also meant that videos could be found on an online portal. ⁴⁹ The transition also meant that vast collections of analog videos would either be converted to digital or lost to history. The former constituted a staggering task, which was possible only for larger publications or campuses with dedicated staff.

A significant recent advancement in the use of video has been its role in telemedicine. Beginning in the 2010s, advancements in high‐speed internet and the proliferation of smartphones and other portable devices enabled the advent of remote health care. For patients with movement disorders, who often experience difficulties with mobility, video consultations provided a lifeline for receiving consistent care without the need for frequent in‐person visits. ⁵⁵ , ⁵⁶ Understanding the value of telemedicine, experts have validated standardized scales for use in telemedicine for specific disorders. ⁵⁵ , ⁵⁶ , ⁵⁷ Nonetheless, telemedicine cannot fully replace the value of an in‐person exam due to significant variability in the recording device and environment, which can affect the accuracy of clinical assessments. This is compounded by the inability to directly perform the physical exam (eg, examining the patient's tone). ⁵⁸

The COVID‐19 pandemic further accelerated the adoption of telemedicine in movement disorders. During a time when in‐person visits were difficult, video consultations became the standard of care for many patients. The wide acceptance of video telemedicine during the pandemic demonstrated its viability as a long‐term solution for managing movement disorders. During COVID‐19 there was an exponential increase in postings on social media of various movement disorders by numerous and widely popular influencers, which lead to an “epidemic” of functional movement disorders, such as “TikTok tics.”

The widespread availability of smartphones for the public offers the opportunity for patients to provide self‐directed at‐home video recordings. The strong value of these recordings for paroxysmal presentations has been thoroughly characterized in the epilepsy literature and is increasingly recognized in the field of movement disorders. ⁵⁹ As pointed out in a recent article by Drs. Andrew Billnitzer and Joseph Jankovic, the value of these recordings is especially high for paroxysmal and fluctuating presentations to aid in assessment and diagnosis. ⁵⁹ , ⁶⁰

Future Directions

Video continues to play an essential role in clinical practice and research in movement disorders. Even after the establishment of consensus criteria for the major movement disorders, the potential of video continues to lie in its ability to capture phenomenology to a more comprehensive extent than words. ²⁸ It also allows the clinician to review the video after the visit, consult colleagues, compare the evolution of the patients' exams over time, and assess their response to treatment. ⁸

The potential of video is now more widely realized and will likely further be expanded with machine learning, motion capture systems, and high‐speed cameras. Motion tracking software allowed for the development of automated systems that quantify motor symptoms, such as tremor frequency and gait disturbances, using video recordings. ⁶¹ , ⁶² , ⁶³ The use of machine learning algorithms to detect novel features of the movement exam is an exciting potential of using artificial intelligence to analyze video recordings. ⁶⁴ In addition, the prospect of combining neurophysiologic and wearable data with video recordings may be an integrative way forward to characterize movement disorders phenomenology. All of this can be viewed as an evolution of the original partnership between clinical acumen and technology, which started with the advent of film.

A final consideration is the need to continue renovating the best practice guidelines for video recordings, which will likely need to be updated for the evolution of personal handheld digital camcorders (eg, smartphones). For the same reason, the new modalities of these devices offer ever‐evolving opportunities to the clinician (eg, slow motion modalities to assess fast movements such as saccades and myoclonus).

Conclusion

Film and video recordings played a central role in the establishment of movement disorders as a subspecialty. The founders of this field, Drs. Fahn and Marsden, were also among the first to understand the value of video recordings, adopt the video rounds as a clinical practice, and implement recording as a daily practice in the lives of movement disorders specialists. They were also largely responsible for the use of video in the context of conferences, most importantly during their legendary annual course at AANAM, an example of a group event where the classification of movement was formalized based on expert and audience discussion and consensus. Videotaping played a crucial role in the formation of the International Movement Disorders Society as it allowed for common definitions of phenomenology to be identified as a core feature of the field. Today, video is found everywhere in the movement disorders community, playing a role within clinical (eg, deep brain stimulation review boards), educational (weekly video rounds in academic centers, educational conferences, and textbooks), and research contexts. The modern history of video technology is inextricably woven with the historical development of the subspecialty.

Author Roles

(1) Research project: A. Conception, B. Organization, C. Execution; (2) Statistical analysis: A. Design, B. Execution, C. Review and critique; (3) Manuscript: A. Writing of the first draft, B. Review and critique.M.R.: 3A, 3BD.C.: 3B

B.B.: 3B

Disclosure

Ethical Compliance Statement: No institutional review board or ethics committee was required for the approval of this study. Informed patient consent was not necessary for this work.We confirm that we have read the journal's position on issues involved in ethical publication and affirm that this work is consistent with those guidelines.

Financial Disclosures for the Previous 12 Months: The authors declare that there are no additional disclosures to report.

Funding Sources and Conflicts of Interest: No specific funding was received for this work. The authors declare that there are no conflicts of interest relevant to this work.

Supporting information

Figure S1. Movement Disorders journal videotape. Kodak Videotape with patient videos associated with the first issue of the Movement Disorders journal.

Figure S2. Movement Disorders journal instructions. Instructions for authors associated with the Movement Disorders journal.

Figure S3. Movement Disorders journal videotape cover. Kodak Videotape cover listing the patient videos associated with the fifth volume of the Movement Disorders journal.

Figure S4. Movement Disorders journal purpose statement. Document outlining the purpose of the journal from Dr. Fahn's files.

Data Availability Statement

Data sharing is not applicable to this article as no datasets were generated or analysed during the current study.