Back to Top Skip to main content Skip to sub-navigation

Researchers find key senses impact readiness, survival

Image of Military personnel in driver and casualty evacuation training. Click to open a larger version of the image. A Soldier assigned to Alpha Company, 24th Military Intelligence Battalion, 66th Military Intelligence Brigade, provides security as part of Anglerfish Day driver and casualty evacuation training at Dagger Complex, Germany in April 2021 (Photo by: Army Staff Sgt. Thomas Mort).

Recommended Content:

Vision and Hearing Loss Prevention | Vision and Hearing Loss Prevention | Hearing and Balance Injuries

Proper hearing in an operational environment is vital to mission success. The loss of this key sense can not only impact unit readiness, but also result in negative consequences for the individual.

"Sound localization is a critical component of situational awareness, or to put it in layman's terms, knowing what is going on around you," said Robert Williams, an engineer with the Defense Health Agency's Hearing Center of Excellence, at Aberdeen Proving Grounds, Maryland.

Recently, military researchers conducted a series of studies to learn more about how hearing can impact situational awareness. They found that service members who could not locate the source of a sound not only had diminished performance, but experienced a higher number of fatalities in the test scenarios.

Service members who took part in the research used programmable headsets during paintball and field exercises to simulate varying levels of hearing loss and how it can affect sound localization. These studies were conducted by Walter Reed National Military Medical Center in Bethesda, Maryland; and Naval Surface Warfare Center Dahlgren Division in Virginia.

"Sounds can be used to draw our attention to certain things, which can then be verified by our eyes," said Williams. "Your eyes can see in front of you, but they don't work as well in the dark, or when obscured by smoke, fog, dust, or other obstacles. But you can hear in the dark, or through fog, and the ability to hear can alert us to hazards or other things that we need to be aware of."

According to Dr. Felix Barker, DHA Vision Center of Excellence, director of rehabilitation and reintegration, vision and hearing are our two most important remote sensing capabilities, and essential to the warfighter.

"When they don't work optimally in a threat situation, this can make the service member effectively "blind or deaf" to the threat," said Barker. "Both senses are also highly interactive. Hearing produces initial awareness of the threat, even when it is coming from behind you. Hearing then helps define the target location so that the threat can be acquired visually, engaged and destroyed."

For those with hearing loss, Williams explained that the ability to localize sounds may also be diminished. "This could occur because they may not be able to hear a sound at all, or because our brains use certain frequencies of sound to determine their location. If we lose the ability to hear these frequencies, we may still be able to hear a sound, but not be able to localize it."

Another factor influencing sound localization is certain types of hearing protection devices, which can cause localization errors and affect situational awareness.

"Unfortunately, hearing protection often diminishes the ability to localize," explained Dr. Theresa Schulz, HCE prevention branch chief. "We lose the information provided by our pinna-- the part of the ear that holds up our glasses. Some hearing protector manufacturers make efforts to minimize the disruption to localization, but none are as good as the open ear. While localization is important, so is protecting the more basic ability to detect, identify and recognize sounds."

"There are a number of studies conducted by the Department of Defense and academia to create localization assessment methods for hearing protection, which have enhanced the DOD's knowledge of how localization affects operational performance,' added Schulz.

Certain military career fields are particularly dependent on a keen ability to localize sound, not only for mission effectiveness, but for survival, according to Schulz. "Ground troops and force protection personnel must be able to localize sounds when on a perimeter watch, for instance, to hear someone approach," said Schulz. "The ability to hear a sound and determine the direction can also help service members find targets. They must be able to detect and localize sounds as well as understand verbal commands whether face-to-face or over a radio."

Studies conducted by the National Institutes of Health show the brain uses many sensory cues to determine the location of a sound. When hearing and vision work together, a person can often determine where sound is coming from faster.

"Both threats and opportunities can be identified using our ears and eyes," explained Schulz. "Hearing a sound is often the first clue to where a sound is coming from, and then we look in a limited area to identify more specifically the source of the sound. Our brains use the difference in loudness between our two ears and the difference in timing of the sound's arrival between our two ears to determine where the sound came from."

By the same token, vision and hearing do not work independently, explained Dr. Mike Pattison, VCE's program manager of readiness and operations optometry. "The two senses work together to create our perception of what we experience in the real world. For most sighted people, in situations where the visual input is unclear such as at dusk or in a dark building, hearing takes on a more prominent role," said Pattison.

Schulz noted that while sound localization is possible with some hearing or vision loss, if both hearing and vision senses are impaired, this ability can become greatly jeopardized.

"Vision and hearing can augment and compensate each other, but if there is a dual sensory loss, much of this critical redundancy is lost. It's so important to always protect your vision and hearing senses by wearing the right protective equipment for your mission, and getting regular hearing and vision checkups to stay mission ready, and to survive and thrive."

You also may be interested in...

New Centers Will Deliver Advanced Care for Serious Eye Injuries

Article
4/27/2022
Army Brig. Gen. Katherine Simonson, Defense Health Agency Deputy Assistant Director of the Research and Engineering Directorate, and Dr. Barclay Butler, Assistant Director for Management, DHA, talks with Army Lt. Col. Samantha Rodgers, Ophthalmology chief (left), during a tour and designation ceremony April 19 at the Ocular Trauma Center – San Antonio Region, Brooke Army Medical Center, Fort Sam Houston, Texas. The designation ceremony marked the launch of DHA’s first Ocular Trauma Center, comprised of personnel from Brooke Army Medical Center and the 59th Medical Group. (Photo: Larine H. Barr, DOD)

The Defense Health Agency launched the first of four Ocular Trauma Centers, which will become primary hubs for the treatment of complex eye injuries and development of cutting-edge research programs.

Recommended Content:

Centers of Excellence | Vision and Hearing Loss Prevention | Vision Center of Excellence | Vision and Hearing Loss Prevention

Wear Approved Safety Eye Protection, Save Your Vision

Article
3/25/2022
Gunner with 1Brigade Combat Team 82nd Division wears shaded eye protection as he fires his M249 at Rotation 21-05 at the Joint Readiness Training Center. (Photo: Capt. Joseph Warren)

The Tri-Service Vision Conservation and Readiness Branch, or TSVCRB, encourages service members to wear eye protection while at work and at home to prevent eye injuries.

Recommended Content:

Vision and Hearing Loss Prevention | Hearing Center of Excellence | Vision and Hearing Loss Prevention | Vision Center of Excellence

Ask the Doc: Can a Concussion Affect Hearing and Vision?

Article
3/16/2022
Elizabeth Kirkpatrick, a physical therapist for the Fort Drum Traumatic Brain Injury (TBI) Clinic, New York, uses a model of the inner ear on Feb. 27, 2019, to demonstrate how a concussion can cause inner ear, or vestibular, damage which may result in dizziness, anxiety, depression, moodiness, balance problems and irritability to name a few. (Photo: Warren W. Wright Jr., Fort Drum MEDDAC)

Even a mild concussion can lead to hearing and vision problems.

Recommended Content:

Traumatic Brain Injury | Traumatic Brain Injury Center of Excellence | Vision and Hearing Loss Prevention | Hearing Center of Excellence | Vision Center of Excellence | Vision and Hearing Loss Prevention | Ask The Doc

Data Registry Helps Improve Research and Treatment for Eye Injuries

Article
3/14/2022
Pvt. Second Class Jagger Dixon, treats an eye injury during Expert Infantryman Badge testing, June 15, 2021, at Fort Polk, Louisiana. Dixon is a soldier with B Company; 2nd Battalion, 4th Infantry Regiment, 3rd Brigade Combat Team, 10th Mountain Division. Soldiers must successfully execute a variety of warrior tasks to earn their EIB. (Photo: Army Spc. Kay Edwards, 27th Public Affairs Detachment)

Eye injury registry (DVEIVR) transforms data into usable information to help improve initial warfighter care and rehabilitation.

Recommended Content:

Centers of Excellence | Vision and Hearing Loss Prevention | Vision and Hearing Loss Prevention | Vision Center of Excellence

It’s True – Carrots (and Other Vegetables) Can Help You See in the Dark

Article
3/4/2022
Each color in fruits and vegetables indicates an abundance of specific nutrients.

Have you ever heard that carrots are good for your eyes, or that they can help you see in the dark? It’s true – carrots are rich in the compound beta carotene, which your body uses to make a form of vitamin A that helps your eyes adjust in the dark. A shortage of vitamin A can cause a host of health problems, including blindness.

Recommended Content:

Nutritional Fitness | Centers of Excellence | Vision and Hearing Loss Prevention | Vision and Hearing Loss Prevention | Vision Center of Excellence

For Thousands of Troops, Eye Surgery is Key to Vision Readiness

Article
2/10/2022
A surgical team with the Warfighter Refractive Eye Surgery Program at Womack Army Medical Center at Fort Bragg monitors the progress of a patient's surgery inside the Ophthalmology Clinic's Refractive Surgery suite.

Helping service members – especially aviators – see clearly without glasses is key to military readiness.

Recommended Content:

Centers of Excellence | Vision and Hearing Loss Prevention | Vision and Hearing Loss Prevention | Vision Center of Excellence

Researchers Connect with Warfighters to Guide Tech Development

Article
1/25/2022
Military personnel trying an immersive training device

Researchers ‘get out of the clinic’ to learn warfighter challenges

Recommended Content:

Research and Innovation | Vision and Hearing Loss Prevention | Vision and Hearing Loss Prevention | Vision Center of Excellence

Military Laser Eye Surgery: Enhancing Vision Readiness

Article
7/12/2021
Military health personnel looking at wavescan results

Enhancing vision readiness through laser eye surgery is now available at 26 military medical treatment facilities.

Recommended Content:

Vision and Hearing Loss Prevention | Vision and Hearing Loss Prevention | Vision Center of Excellence

Mobile hearing test system enables quicker diagnosis, treatment

Article
7/8/2021
Military personnel during a hearing test

Portable device can detect hearing loss in remote areas, clinic settings and beyond.

Recommended Content:

Centers of Excellence | Vision and Hearing Loss Prevention

Ask the Doc: Eye Need Answers

Article
7/8/2021
Senior Airman Mitchel Delfosse, 22nd Aircraft Maintenance Squadron electrical environmental system journeyman, attends an eye exam appointment Jan. 30, 2020, at McConnell Air Force Base, Kansas. Maj. (Dr.) Gerardo Robles-Morales, 22nd Operational Medical Readiness Squadron optometry flight commander, recommends an eye exam a minimum of every two years to ensure overall eye health and correct vision. (U.S. Air Force photo by Airman 1st Class Alexi Bosarge)

Dear Doc: I consider myself pretty lucky. I'm in my late 20s and I've never had any eye problems to speak of. I have 20/20 vision and I've never worn glasses. But...the Air Force tells me to protect my eyes and I'm not exactly sure what that means. Do you know anyone who can give me some solid advice on the best options for eye protection? What should I be wearing at work or on the flight line? What should I be wearing out in the sun? I know I have a lot of questions, but I just want to protect myself as best as possible. Thanks in advance, Doc! -Eye Need Answers

Recommended Content:

Vision and Hearing Loss Prevention | Ask The Doc

Vision Care Service Coordinators Support Ocular Care Management

Article
6/24/2021
Military health personnel giving an eye appointment

Vision care service coordinators support eye injury and vision loss patient recovery.

Recommended Content:

Centers of Excellence | Vision and Hearing Loss Prevention | Vision and Hearing Loss Prevention

Patients Contribute to Shape Future Hearing Loss Treatment

Article
6/21/2021
Barbara Kelly from the Hearing Loss Association of America hosting a meeting

Patient-focused meeting could lead to improved hearing loss therapies

Recommended Content:

Centers of Excellence | Vision and Hearing Loss Prevention | Hearing and Balance Injuries | Vision and Hearing Loss Prevention

Cataracts Concern Battle Fighters, the Aging

Article
6/21/2021
A doctor performing cataract surgery

Traumatic cataracts can occur during battlefield injuries, but they are largely avoidable in non-combat situations.

Recommended Content:

Centers of Excellence | | Vision and Hearing Loss Prevention | Vision and Hearing Loss Prevention

MHS and MOS Town Hall: "To Your Health"

Article
6/8/2021
Images of Dr. Theresa Schulz and Colonel Mark Reynolds

MHS and Military OneSource: To Your Health: A Discussion with experts from the Hearing Center of Excellence and the Vision Center of Excellence

Recommended Content:

Vision and Hearing Loss Prevention | Vision and Hearing Loss Prevention | Hearing and Balance Injuries |

How vision and hearing contribute to service members’ readiness

Article
5/26/2021
Military personnel preparing for night vision training

Hearing and sight are the two dominant human senses, both primordial for military service members’ readiness, health, and mission success.

Recommended Content:

Centers of Excellence | Vision and Hearing Loss Prevention | Vision and Hearing Loss Prevention
<< < 1 2 > >> 
Showing results 1 - 15 Page 1 of 2

DHA Address: 7700 Arlington Boulevard | Suite 5101 | Falls Church, VA | 22042-5101

Some documents are presented in Portable Document Format (PDF). A PDF reader is required for viewing. Download a PDF Reader or learn more about PDFs.