Edited by: Daniel Ortuño-Sahagún, Universidad de Guadalajara, Mexico
Reviewed by: Yasuo Terao, Kyorin University, Japan; José M. Delgado-García, Universidad Pablo de Olavide, Spain
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Visual function is a major area of decline in Parkinson’s disease (PD) progression and healthy aging adults (
Various treatments, including electrical brain stimulation, have been suggested for improving voluntary saccade function in PD (
Recent work has investigated the difference between smooth-pursuit performance in persons with PD and persons with no known neurological disorders (
Identifying non-invasive biomarkers of PD onset is imperative for disease treatment. Saccadic abnormalities have been suggested as a diagnostic tool for PD, including early stage progression marking and differential diagnosis from other tremor disorders such as essential tremor (
One criticism against saccade measurements as a diagnostic tool for PD is that the abnormalities seen in saccadic movements tend to differ based on the experimental context (
Risks associated with eye training include the possibility of eye strain and orbital myositis, which is a rare autoimmune disorder that may result from inflammation due to vigorous exercise. These risks are minimal and reduced by the progressive periodization of amplitudes in the training regimen. The potential benefits of improved eye coordination, range of motion, and responsivity to visual stimuli outweigh the minimal risk for eye strain/injury. The greatest amount of risk in the study is associated with performing OFF-state assessments in participants with PD. The OFF-state occurs when the motor effects of levodopa and other dopaminergic medications are not present due to delayed intake of these medications. During the OFF-state, intensified motor symptoms that may be uncomfortable – such as dyskinesia, rigidity, spasticity, bradykinesia, dystonia, and freezing – may be present. However, discomfort and possible risk of falls are mitigated by limiting the inclusion criteria to only include individuals in the early stage of the disease (H&Y score 1–2; see
Criteria for Hoehn & Yahr stages one and two.
H&Y: Stage One | H&Y: Stage Two |
---|---|
1. Signs and symptoms on one side only | 1. Symptoms are bilateral |
2. Symptoms are mild | 2. Minimal disability |
3. Symptoms are inconvenient but not disabling | 3. Posture and gait affected |
4. Usually presents with tremor of one limb | |
5. Friends have noticed changes in posture, locomotion, and facial expression |
It is common practice to perform assessments in the OFF-state in the field of PD clinical research because the methodology provides a controlled environment for assessing the disease without the influence of movement-modifying medications that mask the disease condition. This is especially important in biomarker research of PD patients. Assessment in the OFF-state condition increases relevance and generalizability of the study evidence to populations with undiagnosed and untreated PD. Generalizability of results may lead to greater instances of early detection and allow for informed diagnoses of individuals not yet receiving movement-modifying medications. The increased applicability of data collected in OFF-state assessments far outweighs the risks.
Due to the current lack of literature studying voluntary saccade training through practice, the training dose of 30 min, twice per week, for four weeks was chosen based on training doses seen in other eye training protocols (
There will be no comparator intervention used in this study. The effects of the voluntary saccade training intervention in persons with PD will be compared to those in persons with no known neurological disorders so that we can determine whether the group with PD is more responsive to the intervention. A greater response in the participants with PD would indicate a significant improvement in saccade performance. A lack of response to the intervention would indicate a resistance to improvement in saccade performance that may be characteristic of persons with PD.
We hypothesize that before and after comparisons of voluntary and reflexive saccade performance will show a greater decrease in latency and the number of saccades needed to reach the target, along with a greater increase in saccade amplitude and velocity in Parkinson’s disease participants as compared to participants with no known neurological disorders.
To determine whether voluntary saccade training decreases voluntary latency, reflexive latency, and number of saccades needed to reach a target amplitude and increases saccade amplitude in persons with PD compared to persons with no known neurological disorders.
To determine whether training voluntary saccades affects motor disability in persons with PD. We will also investigate whether training voluntary saccades affects the relationship of the main sequence. Should statistical analysis reveal that these improvements are absent in participants with PD, we propose that saccade performance would be a potential early PD biomarker.
This trial is designed as a two-arm, pre-post, single center pilot trial with an equal number of participants with PD and participants with no known neurological disorders (control), which will be analyzed using an analysis of variance (ANOVA) with mixed effects.
All data collection and participant training will be conducted in the Neuroscience of Dance in Health and Disability (NDHD) Laboratory at the University of Illinois at Urbana–Champaign. Access to the laboratory space is limited to the research team and participants, with a partitioned area for saccade training and eye tracking data collection. This protocol has been approved by the local IRB and all NDHD laboratory staff have completed the ethics and best practices training required by the local IRB and the University of Illinois. Due to the small size of this study, Champaign County, Illinois will be sufficient for the recruitment of both study groups. The adult population of Champaign County is approximately 170000 persons and is largely rural. We will attempt to representatively recruit participants according to the ethnicity data provided by the US Census Bureau: 72.4% White, 13.4% Black or African American, 0.4% Native American, 10.9% Asian, 0.1% Native Hawaiian and other Pacific Islander, 2.8% two or more races, and 6.0% Hispanic or Latino
A final decision on inclusion will be made in consultation with the principal investigator once all screening materials are complete (see
Eligibility criteria for protocol.
1. To be medically stable with diagnosis of PD by meeting the United Kingdom PD Society Brain Bank Criteria OR- no known neuromuscular disorders for the for the control group. |
2. To have a Modified Hoehn & Yahr stage 1–2 (with unilateral involvement only, unilateral and axial involvement, and bilateral involvement without impairment of balance) in the conventionally defined OFF medication state. |
3. To have medical clearance form from their physician for participation in the study. |
4. To be in a stable regimen of PD medication 30 days prior to the initiation of the study and until the completion of the study. |
5. To be willing and able to provide informed consent. |
6. To be of age 40 and up. |
7. Must have a caregiver/family member present for OFF-state assessment sessions. |
1. Presence of dementia based on The Montreal Cognitive Assessment (MOCA) – score of less than 25. |
2. Diagnosis of comorbid neurological disorder such as epilepsy. |
3. History of neurological injury such as stroke. |
4. History of brain surgery such as deep brain stimulation. |
5. Concurrent severe medical illness which in the opinion of the research team will preclude participation in the study (such illnesses may include but not limited to severe or uncontrolled cardiovascular disease, hypertension, pulmonary disease, or diabetes). |
6. Inability to attend and participate in at least seven of the training sessions. |
7. Uncorrected vision, history of retinal disease (e.g., macular degeneration), presence of optic neuropathy due to glaucoma or ischemic optic neuropathy, pseudoexfoliation syndrome, ocular surgery, ocular trauma, visually significant cataract, orbital myositis, blindness or refractive errors outside –5 to +3 D. |
8. Indication by the participant s neurologist in the medical release form that testing the participant in the OFF-medication state would put PD participants at significant risk for medical complications. |
Training and testing will be performed using the SR EyeLink II eye tracking system (SR Research). The EyeLink II system for assessments and training has two cameras on a head mount located directly below eye level. The pupil is tracked by a device that captures infrared light reflected off the lens and cornea of the eyes. The lens, cornea, and other parts of the eye absorb a small amount of energy from infrared light, but the energy is less than 18% of the Maximum Permissible Exposure level as certified by the American Standards Institute (ANSI Z 136.1-1973). The EyeLink II system will be mounted to the participant’s head using the adjustable straps, such that the head camera bar will be parallel to the display screen, on which four infrared emitters will be placed in a rectangle. The participant will be then positioned, using a chin rest support, so that the participant’s resting focus point will be at the center fixation target display on the screen in the middle of the rectangle of emitters. The experimenter will position the eye tracker on the participant’s head so that the participant can see targets displayed at the amplitude of interest. The chin rest also serves to isolate eye-movements from head movements during eye tracking and maintain a set distance from the display screen. A Sharp Aquos 178.5 cm by 100 cm television will be used as the display for the participant (Sharp Corporation, Sakai-ku, Sakai, Japan). This screen mirrors the computer display visible to the experimenter during training and testing sessions. A second host computer runs the SR Research data capture and processing during sessions. The host computer also displays pupil position and the view of the left and right eye cameras in real time. After adjusting the eye cameras and pupil threshold to track the pupils moving in the eight cardinal and intercardinal directions, the cameras will be then calibrated using the SR Research program. The experimenter will then perform a validation of the camera calibration prior to beginning a training or testing block.
Over the course of the four-week intervention period, participants will undergo eight training sessions of 30 min each. During each training session, three target amplitudes will be trained on the six target amplitudes: 10°, 20°, 30°, 40°, 45°, and 50°. Each amplitude will be trained in two different training sessions over the course of the intervention period. This follows an intercalated training schedule of progressive and regressing load design (see
Training schedule of amplitudes. On both sessions of each week, the same three amplitudes will be trained.
Week | Amplitudes Trained |
---|---|
1 | 10°, 20°, 30° |
2 | 10°, 20°, 40° |
3 | 20°, 30°, 45° |
4 | 20°, 40°, 50° |
Every trial consists of a fixation period, target circle presentation period, direction indication period, and resetting period (see
Example training/testing trial display sequence.
Participant flow timeline.
Example reflexive testing trial display sequence.
Participants who are unable to complete seven of the eight training sessions due to fatigue or other events related to the intervention will be omitted from the study and receive prorated compensation. The intervention is designed to minimize fatigue by providing rest breaks regularly and as the participant indicates a need for rest. During both the training and testing sessions, eye tracking data will be collected by the SR Eyelink II system and stored. While only testing session data will be analyzed to determine the effects of the intervention, training session data can be used to check that training sessions will be completed per the protocol instructions. This check data includes the number of trials per direction per amplitude, amplitudes trained, and collection dates for each session.
In the unlikely case of an unexpected event, the research team, in consultation with the participant’s physician, will make the decision to modify or terminate the trial. As this is a pilot trial, there will be no adjustment to sample size in the course of the study.
Involvement in other interventional studies will not be permitted for participants in either group.
Participants will continue their physician prescribed treatment during their participation.
The primary outcomes of this study are four measures of voluntary and reflexive saccade performance: (1) the normalized amplitude calculated as the amplitude of the saccade divided by the target eccentricity, (2) the mean normalized saccadic velocity calculated as the mean normalized amplitude divided by saccade duration, (3) saccadic latency calculated as the time from the presentation of the directional cue to the saccade onset. The saccade onset is calculated as the time between the presentation of the directional arrow and the first eye movement crossing the velocity threshold of 30°/s and the acceleration threshold of 8000°/s2 specified by the EyeLink® II User Manual (
One secondary outcome for this study is Movement Disorder Society-sponsored new version of the Unified Parkinson’s Disease Rating Scale (MDS-UPDRS). The MDS-UPDRS assesses motor examination and complications, motor aspects of daily living, and non-motor aspects of daily living using a combination of questionnaire and task performance assessment (
Primary outcomes will be assessed by a member of the NDHD laboratory staff blinded to secondary outcome assessment, which will be performed on a separate day (see
Timeline of participant involvement.
Study Period |
||||||
Enrolment |
Allocation |
Post-allocation | ||||
---|---|---|---|---|---|---|
Timepoint | ||||||
Eligibility screen | X | |||||
Informed consent | X | |||||
Medical release | X | |||||
Allocation | X | |||||
Parkinson’s group | X | X | X | X | ||
Healthy group | X | X | X | X | ||
Clinical Screening | X | |||||
Saccades | X | X | ||||
Clinical | X | X |
There will be two groups with the same treatment: (1) a control group of participants with no known neurological disorders and (2) a test group comprised of participants with PD that have H&Y levels 1–2. In the absence of existing data in the literature to estimate the required same sample size for a protocol of this nature, the estimation is based on the number of eyes tested and trained in other eye movement studies and a 10% attrition rate seen in other studies performed by the authors (
Persons with PD (
During the week prior to and the week following the intervention period, participants will be tested for both voluntary and reflexive saccade performance (see
Investigator team activity timeline.
Approximate | Prestudy | Basline/ | Intervention | |||||||
---|---|---|---|---|---|---|---|---|---|---|
PD Only | time to | screening/ | Intervention | Intervention | Intervention | week 4/ | ||||
Activity/assessment | (Yes/ | No) | Staff member | complete | (min) | consent | week 1 | week 2 | week 3 | conclusion |
Prescreening consent | Study coordinator | 5 | X | |||||||
Screening checklist | Study coordinator | 10 | X | |||||||
Consent form | Study coordinator | 45 | X | |||||||
Medical release and relevant medical history | Yes | Potential participant’s neurologist | 30 | X | ||||||
Hoehn and Yahr scale | Yes | Clinical assessors | 30 | X | ||||||
Montreal Cognitive Assessment | Yes | Clinical assessors | 30 | X | ||||||
Unified Parkinson’s Disease Rating Scale | Yes | Clinical assessors | 30 | X | ||||||
Voluntary saccade assessment | Staff member | 45 | X | |||||||
Reflexive saccade assessment | Staff member | 45 | X | |||||||
Voluntary saccade training intervention | Staff member | 45 | X X | X X | X X | X X | ||||
Termination form | Study coordinator | N/A | X | |||||||
Serious adverse event form | Study coordinator | N/A | As needed throughout protocol | |||||||
Progress note | All team members | N/A | X | X | X | X | X | |||
Communication log | All team members | N/A | Every phone or in-person contact outside of regular study visits |
Saccade testing summary table.
VOLUNTARY | REFLEXIVE |
---|---|
Southwest, South, Southeast, East, Northeast [8 total] | Southwest, South, Southeast, East, Northeast [8 total] |
Participants will perform eye-tracking related assessments in ON and OFF motor-related medication states in order to completely characterize the effects of eye-movement training in PD (see
OFF-state testing timeline for participants.
Night Before | 7:00 AM | 8:30 AM | 9:00 AM | 10:00 AM |
---|---|---|---|---|
Take last dose of medication at 11 PM (taken 8 h before morning assessment) | Eye-Tracking Assessment (OFF-state) | MDS-UPDRS Assessment | Eye-Tracking Assessment (ON-state) |
Following completion of eye-tracking related assessments, the participant’s motor function will be assessed using the Movement Disorder Society-United Parkinson’s Disease Rating Scale (MDS-UPDRS) in the OFF-state for an accurate description of PD stage. To achieve the OFF-state, participants will be instructed to take their last dose of medication approximately 8 h before their scheduled morning assessment. This approach will time the initiation of the OFF-state with the beginning of data collection. Immediately following the OFF-state eye-tracking assessment, the MDS-UPDRS will be administered to participants in the NDHD Laboratory which is equipped with ballet barres for support. Immediately after the MDS-UPDRS administration, participants will be instructed to take their medication and take a 60 min long break while they return to their normal ON-state. This protocol will mitigate the time spent in the OFF-state to approximately 2 h. Sixty-minutes after the intake of medication, participants will complete a final eye-tracking assessment in the ON-state. In total, pre/post-assessments will last at most 4 and a half hours, including the 60 min break and assessment beaks. A summary of an example Parkinson’s pre-training and post-training assessment timeline follows: If the participant takes medications in a schedule other than every 8 h, the participant will time the start of the experiment with their regular time of medication intake and withhold from taking their regular dosage for the first 2 h of the experiment. After those 2 h, the participant will resume regular medication intake.
Eye tracking data for both the left and right eyes is first converted to ASCII files, which will be then converted into two types of ASCII files: gaze data, which consisted of pupil position relative to the room, and head referenced (
All participants will be assigned a code for de-identification for all data collected. The participant code will be stored in a locked cabinet and destroyed when the study procedures are completed. Data analyses will be conducted on the coded non-identifiable data. All data will be kept in a locked file cabinet or in encrypted, password protected research computers. We will retain all screening data for those who qualify and volunteer and destroy the screening data for those who are excluded or do not choose to participate in the study. The informed consent, medical clearance, and verification of PD diagnosis will be stored together in a locked cabinet.
After data cleaning is completed using the automatic and user-guided portions of the MATLAB program, the cleaned data for all trials, which contains pupil position data for both eyes, will undergo statistical analysis. Using SAS, an ANOVA with mixed effects will be performed using the finalized data concerning four variables of interest for both voluntary and reflexive saccades: (1) normalized mean velocity, (2) normalized angular distance, (3) latency for the first saccade in a trial, and (4) saccade count to target (SAS Institute Inc., Cary, NC, United States). For participants with PD, the UPDRS scores before and after the intervention will be included with the eight saccade variables in the ANOVA with mixed effects to determine if any significant clinical mobility improvements occur. In secondary analyses, saccade-related measurements will be compared between the voluntary and reflexive saccades and by target amplitude. In the case of non-normality, non-parametric statistical methods will be used. Saccade data that are not viable for statistical analysis due to problems in recording eye movements, such as blinks obscuring saccades and loss of fovea tracking during a saccade initiation or endpoint, will not be included in the statistical analyses. Main sequence analysis will be included as a secondary form of analysis. Due to the comparatively weaker relationship seen between peak velocity and amplitude in the range that will be recorded, analysis of the relationship between mean velocity and amplitude and the relationship between duration and amplitude will be included (
Due to the low risk of this protocol, no data monitoring committee is required.
Should the intervention cause orbital myositis or other physical injuries in any of the participants, the research team, in consultation with the patient’s physician, will make the final decision to terminate the trial.
Data collected with the eye tracker during assessments in the study will not give an immediate indication about participant risk. However, participant comfort and concern for their own health will be continuously monitored verbally by research personnel throughout the assessment. If the participant expresses concern all research procedures will stop and research personnel will call 911 with the participant’s consent. In case of such an adverse event the IRB will be immediately notified. The participants are required to have a caregiver/family member present during OFF-assessments. There will be an area on the physician clearance form (Supplementary Material Data Sheet
The trial will be audited by compliance entities associated with the University of Illinois at Urbana–Champaign system.
Improvement in voluntary saccade function may occur due to changes at multiple levels of the saccade. Saccade improvements may occur due to increased eye muscle strength as well as better nervous system planning and control of saccades. Three sets of extraocular muscles are involved in performing saccades depending on their component composition (
The superior colliculus (SC) has been identified as a key area for target and timing selection for saccades in primates (
A lack of response to voluntary saccade training in the primary or secondary outcome measures would support the use of this protocol for testing saccades as part of a biomarker assessment for early detection and diagnosis of PD. An added dimension of biomarker potential may come from a differential response of the main sequence to the training between the two groups as measured by changes in characteristic peak velocity for given saccadic amplitudes. This would create a more robust saccade-based biomarker by adding a treatment-response dimension to the characterization suggested as a diagnostic tool by previous studies (
This intervention holds significant promise as a low-cost, low resource-demand tool to improve motor functions of the eyes in persons with PD and adults with no known neurological disorders as well as mobility outcomes associated with eye function in persons with PD. Should persons with PD not show improvements on any metric following the intervention, a lack of response to voluntary saccade training may support saccade assessment as a biomarker for early detection and diagnosis of PD.
All methods have been approved by the local IRB committee (see
IRB protocol revision chronology.
July 2, 2015 | ||
Approval date | January 15, 2016 | |
Amendment 01 | February 16, 2016 | Update of research team list. |
Amendment 02 | October 3, 2016 | Change in research location to Freer Hall room 250. |
Amendment 03 | July 31, 2017 | Addition of testing in the off-medication state for participants with PD. |
Amendment 04 | April 9, 2018 | Update of research team list. |
Amendment 05 | July 19, 2018 | Medical release form specific to healthy controls added. |
Trial registration data.
Primary registry and trial identifying number: 17784042 |
Date of registration in primary registry: July 25, 2018 |
Secondary identifying numbers: N/A |
Source(s) of monetary or material support: Unfunded |
Primary sponsor: University of Illinois at Urbana–Champaign |
Secondary sponsor(s): None |
Contact for public queries: CLO, Ph.D., MA lopezort@illinois.edu |
Contact for scientific queries: CLO, Ph.D., MA University of Illinois at Urbana–Champaign |
Public title: Voluntary saccade training in persons with Parkinson’s disease and healthy adults |
Scientific title: Voluntary saccade training in persons with Parkinson’s disease and healthy adults – two-arm, pre/post-trial |
Countries of recruitment: United States of America |
Health condition(s) or problem(s) studied: Parkinson’s disease, voluntary saccades, reflexive saccades |
Intervention: Voluntary saccade training |
Key inclusion and exclusion criteria: Ages eligible for study: ≥40 years; Sexes eligible for study: both; Accepts healthy volunteers: yes |
Inclusion criteria: For participants with PD: (1) medically stable with diagnosis of PD by meeting the United Kingdom PD Society Brain Bank Criteria, (2) to have a Modified Hoehn & Yahr stage 1–2 (with unilateral involvement only, unilateral and axial involvement, and bilateral involvement without impairment of balance) in the conventionally defined OFF medication state, (3) to have medical clearance form from their physician for participation in the study, (4) to be in a stable regimen of PD medication 30 days prior to the initiation of the study and until the completion of the study, (5) to be willing and able to provide informed consent, (6) to be of age 40 and up, and (7) must have a caregiver/family member present for OFF-state assessment sessions. |
For neurologically healthy participants: (1) no known neuromuscular disorders, (2) to have medical clearance form from their physician for participation in the study, (3) to be willing and able to provide informed consent, and 4) to be of age 40 and up. |
Exclusion criteria: (1) presence of dementia based on The Montreal Cognitive Assessment (MOCA) –score of less than 25, (2) diagnosis of comorbid neurological disorder such as epilepsy, (3) history of neurological injury such as stroke, (4) history of brain surgery such as deep brain stimulation, (5) concurrent severe medical illness which in the opinion of the research team will preclude participation in the study (such illnesses may include but not limited to severe or uncontrolled cardiovascular disease, hypertension, pulmonary disease, or diabetes), (6) inability to attend and participate in at least seven of the training sessions, (7) uncorrected vision, history of retinal disease (e.g., macular degeneration), presence of optic neuropathy due to glaucoma or ischemic optic neuropathy, pseudoexfoliation syndrome, ocular surgery, ocular trauma, visually significant cataract, orbital myositis, blindness or refractive errors outside –5 to +3 D, (8) indication by the participant’s neurologist in the medical release form that testing the participant in the OFF-medication state would put PD participants at significant risk for medical complications. |
Study type: Interventional |
Allocation: no randomization; Intervention model: two-arm pre-post; Masking: non-masked |
Primary purpose: eye movement training |
Study Phase: Phase 0 |
Date of first enrolment: March 12, 2016 |
Target sample size: 44 |
Recruitment status: Recruiting |
Primary outcome(s): For both voluntary and reflexive saccades: number of saccades needed to reach target amplitude, for first saccade: latency, normalized mean velocity, normalized amplitude |
Key secondary outcomes: Unified Parkinson’s Disease Rating Scale |
IRB# 16033
Issue date: July 19th, 2018
Protocol amendment number: 06
Authors: Paul B. Camacho
Important protocol modifications will be approved by the local IRB and communicated to co-investigators, trial participants, trial registries, the clinical trial publishing journal.
The written informed consent will be completed by the participant before enrolling in the study and undertaking baseline data collection. The participants will have the opportunity to read the informed consent and ask any questions about the procedures to the PI before participation in the study. We will provide the participant with a copy of the signed informed consent document. We will give a period of at least 24 h for review of the consent form. This will assure that the participant has had ample time in reviewing and understanding the consent form prior to signing. The PI will be available to answer any questions regarding the consent form.
All biographical and medical information about potential participants will be stored in paper form in a locked cabinet. We will retain all screening data for those who qualify and volunteer. We will destroy the screening data for those who are excluded or do not choose to participate in the study. All participants will be assigned a random identification number for all data collection. The participant identification code will be stored in paper form and destroyed when the study procedures are completed. Clinical measures taken to as part of the recruitment process and study will be deidentified, using assigned participant numbers, and completed in paper form. Raw eye tracking data will be collected and stored by participant number on a computer, which will have no internet connection. Access to the NDHD laboratory is restricted to trained staff and, during training or testing, the participants and their caregivers. At no point will anyone who is not a member of the NDHD staff have access to any collected data. Data analyses will be conducted on the coded non-identifiable data. The data will be kept for 5 years after publication, as required by the American Psychological Association. Only deidentified data will be released after the trial as part of peer-reviewed scientific journal articles and storage in a data repository.
The final trial de-identified dataset will be available to members of the NDHD laboratory staff and stored in an online data repository. To minimize bias, investigators performing data processing of eye tracking data will not have access to clinical measure outcomes or identifying information until the end of the study. Similarly, clinical assessors will not have access to eye tracking data or other information that could bias assessment.
Study participants will continue with regular, prescribed medical care throughout the experiment. In the event of physical injury, their physician will be contacted.
The proposed forms of dissemination are presentations at scientific conferences and publications in scientific journals. Only deidentified data will be released after the trial as part of peer-reviewed scientific journal articles and storage in a data repository. To be eligible for authorship, all potential authors must meaningfully contribute to and approve the final manuscript. All authors are expected to contribute to the shaping of the protocol and performance of some aspect of the study. The full protocol and statistical code will be accessible via an online data repository, along with the participant-level dataset for the purposes of study reproducibility.
Trial Sponsor: University of Illinois at Urbana–Champaign
Sponsor’s Reference: N/A
Contact name: Dr. Citlali López-Ortiz
Address: 221 Freer Hall 906 S Goodwin Ave. Urbana, IL 61801
Telephone: (217) 300-1022
Email: lopezort@illinois.edu
The sponsor will have no direct role in study design, data collection, management, analysis, interpretation of data, writing of the report, or decision to submit the report for publication.
CL-O conceived the study and design and involved in all aspects of the study. AK supervised the experiments design. CZ assisted with medical aspects of the protocol design. PBC helped refine the study design and wrote the manuscript. RC set up the eye tracker and computing systems and developed the data processing software. RC and PBC helped with implementation. SS contributed with statistical expertise. All authors contributed to refinement of the study protocol, approved the final manuscript, and agreed to be accountable for the content of the manuscript.
The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.
We express our gratitude to the staff of the Neuroscience of Dance in Health and Disability Laboratory for their assistance in testing the experimental set up and other aspects of this protocol, along with Reika McNish and Nathaniel Speidel for their assistance in proofreading and editing this manuscript. We thank the staff of the Department of Kinesiology and Community Health, the College of Applied Health Sciences, the Center on Health Aging and Disability, and the Beckman Institute for Advanced Science and Technology at the University of Illinois at Urbana–Champaign for equipment support. We also thank the participants, current and future, for participation in this protocol.
The Supplementary Material for this article can be found online at: