Wearable Echolocation Aids Using Parametric Sound

Overview

The objective of this study is to study a novel device designed to aid patients with impaired vision to safely navigate their environment. Subjects for this study will be individuals with normal vision, either with or without correction. The subjects will wear a device to simulate impaired vision and will be asked to walk a path with randomly placed obstacles during two trials. One of the trials will consist of the subject wearing the simulator alone. The other trial will consist of the subject wearing the simulator and the study device. The study device is designed to be worn by the study subject and will emit tones to indicate obstacles in the environment as the subject walks on the path with random obstacles. The tones will indicate that there is an obstacle in the individual's path and will increase in intensity as the subject moves closer to the object.Invest

Detailed description

The objective of this project is to study visually impaired individuals' ability to develop echolocation skills using simple, wearable, echolocation devices that will not be cost prohibitive to most Americans and that would allow for greater availability to the visually impaired community. These echolocation devices emit parametric sound, a directional beam of ultrasound waves that interact with sound waves and surrounding objects, through goggles, watches, lanyards or even walking canes. This allows the visually impaired individual to detect sound waves as they reflect off their surroundings and return to the patient's ears in unique patterns resembling their external environment. This device would enable individuals to create a raw mental image of their surroundings and any obstacles along their path.

The primary endpoint for this pilot study is to assess the feasibility of such echolocation devices as an adaptive low vision navigation aid on healthy subjects using low vision simulation goggles. Several metrics will be observed and recorded to measure how well echolocation technology addresses challenges associated with visual impairment and downstream factors. These metrics will include gait initiation, termination analysis via the Zeno-Walkway system, electromyography (EMG) of key muscles involved in gait termination, participant preference of echolocation wearable device modularity, and general survey questions.

The secondary study endpoint is to implement the use of echolocation technology among members of the blind or visually impaired population as a clinical aid and study the impact that this technology has on their quality of life and added downstream health implications longitudinally.

A final objective of this study is to seek feedback, not only on the use of any echolocation device to navigate but, to obtain feedback on subjects' experience with the specific study device, the Wearable Echolocation Device.

Interventions

• Device Wearable Echolocation Device
  The device features many parametric speakers housed in a plastic case. The parametric speakers emit directional sound waves that return to the source with varying wavelengths depending on the distance of the surrounding objects. The device is designed to be worn by the subject either using a lanyard on the subject's neck, or on the subject's wrist.

Primary outcome measures

• Change in Stride Length for Visually Impaired Individuals with Implementation of Echolocation Technology [Time frame: Baseline (pre-training) and immediately post-training (same 30 minute session)]
• Change in Cadence for Visually Impaired Individuals with Implementation of Echolocation Technology [Time frame: Baseline (pre-training) and immediately post-training (same 30 minute session)]
• Change in Walking Velocity for Visually Impaired Individuals with Implementation of Echolocation Technology [Time frame: Baseline (pre-training) and immediately post-training (same 30 minute session)]
• Change in Body Mass Index (BMI) for Visually Impaired Individuals with Implementation of Echolocation Technology [Time frame: Baseline (pre-training) and immediately post-training (same 30 minute session)]

Eligibility criteria

Inclusion criteria

• Subject has provided informed consent in a manner approved by the Institutional Review Board (IRB) and is willing and able to comply with the trial procedures.
• Adults at least 18 years of age and no older than 100 years of age at the time of consent.
• Individuals in good health who can perform daily activities without assistance and can walk independently.
• Normal vision (with or without corrective lenses) if there is no uncorrectable visual impairment.

Exclusion criteria

• History of gait problems.
• Foot or leg impairments.
• Hearing impairment.
• Vertigo or other balance problems.
• Pregnant individuals.
• Any medical condition that, in the opinion of the investigator, would place the subject at increased risk for participation.
• Medications that may cause dizziness or weakness.
• Concurrent participation on another research study.
• Use of an investigational agent in the 30 days prior to signing informed consent.
• History of prior non-compliance.
• Presence or history of psychiatric condition (including anxiety, psychosis, drug, or alcohol addiction) that would, in the opinion of the investigator, make it difficult for the subject to comply with the study procedures or follow the investigators instructions.
• Non-English-speaking individuals.
• Individuals from special or vulnerable populations (i.e., adults unable to consent, minors, incarcerated individuals).
• Body weight greater than 700 pounds.

Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.

Healthy volunteers: Yes

Study design

Allocation

Randomized

Model

Parallel assignment

Masking

Single blind

Primary purpose

Other

Study locations

United States · 1 center

• University of Texas Medical Branch — Galveston

Publications

• GBD 2019 Blindness and Vision Impairment Collaborators; Vision Loss Expert Group of the Global Burden of Disease Study. Trends in prevalence of blindness and distance and near vision impairment over 30 years: an analysis for the Global Burden of Disease Study. Lancet Glob Health. 2021 Feb;9(2):e130-e143. doi: 10.1016/S2214-109X(20)30425-3. Epub 2020 Dec 1. PMID 33275950
• Varadaraj V, Ehrlich JR, Swenor BK. Vision Impairment Has Implications for Aging and Health Outcomes, Beyond Ophthalmology. JAMA Netw Open. 2022 May 2;5(5):e2214610. doi: 10.1001/jamanetworkopen.2022.14610. No abstract available. PMID 35608864
• Ong SR, Crowston JG, Loprinzi PD, Ramulu PY. Physical activity, visual impairment, and eye disease. Eye (Lond). 2018 Aug;32(8):1296-1303. doi: 10.1038/s41433-018-0081-8. Epub 2018 Apr 3. PMID 29610523
• Thaler L, Goodale MA. Echolocation in humans: an overview. Wiley Interdiscip Rev Cogn Sci. 2016 Nov;7(6):382-393. doi: 10.1002/wcs.1408. Epub 2016 Aug 19. PMID 27538733
• Swenor BK, Ehrlich JR. Ageing and vision loss: looking to the future. Lancet Glob Health. 2021 Apr;9(4):e385-e386. doi: 10.1016/S2214-109X(21)00031-0. Epub 2021 Feb 16. No abstract available. PMID 33607013
• Sohl-Dickstein J, Teng S, Gaub BM, Rodgers CC, Li C, DeWeese MR, Harper NS. A Device for Human Ultrasonic Echolocation. IEEE Trans Biomed Eng. 2015 Jun;62(6):1526-1534. doi: 10.1109/TBME.2015.2393371. Epub 2015 Jan 16. PMID 25608301
• Norman LJ, Dodsworth C, Foresteire D, Thaler L. Human click-based echolocation: Effects of blindness and age, and real-life implications in a 10-week training program. PLoS One. 2021 Jun 2;16(6):e0252330. doi: 10.1371/journal.pone.0252330. eCollection 2021. PMID 34077457

Identifiers

NCT: NCT07218991 · 24-0032

Primary sources (government registries)

• ClinicalTrials.gov (US NIH)

View this study on ClinicalTrials.gov ↗