Assistive technologies

Acoustic headband with ear trumpets, Europe, 1901-1930

Some important medical technologies do not cure conditions. Instead they support our bodies’ functions.

Understanding healthy body function in the 1800s

During the 1800s, biomedical scientists investigated how the body functioned. They examined many bodies and set limits for healthy body function. This helped doctors identify and understand disease. Doctors, engineers and inventors used this information to build machines to replicate certain healthy organs.

Designing machines for hospital, home and body

In the 20th century many machines were built to take over from bodies when they stopped working. In the 1920s iron lung breathing machines were developed. By the 1950s they were replaced by ventilators. Doctors found them less bulky and they gave better control. For patients the complete confinement of the iron lung was replaced by the invasive discomfort of the ventilator tube. However, both machines kept them alive.

Machines assisting the organs of critically ill patients became central to intensive care medicine in hospitals. However, devices such as kidney dialysis machines could be used in the patient’s home. Other organ-assisting devices were implanted into the body. The pacemaker machine regulated the heartbeat and was invented by Albert Hyman in 1932. In 1958, Arne Larson received the first fully implanted pacemaker.

Replacing body parts

Technology to replace lost or surgically removed body parts was as important as machines assisting function. Prosthetics, replacements for limbs and other body parts, have been used since ancient times. Wheelchairs were developed alongside prosthetics to enhance mobility. Dentures are prosthetics used to replace missing teeth. Since around 700 BCE, dentures have helped restore the face’s former appearance as well as the ability to chew food and speak clearly. Technologies embedded in the body, such as artificial hearts, hips, and knees, became common in the late 20th century.

Hearing aids and technology to assist sight

Medical technology can also assist impaired senses, especially sight and hearing. Ear trumpets were popular in the early 1800s. These horn-shaped devices directed and amplified sound into the ear. They were more sophisticated and effective than earlier hearing aids. Electric hearing aids appeared at the start of the 20th century. Improvements in technology shrunk them. By the 1950s, transistor technology meant devices could be worn behind the ear. The 1980s saw hearing aids small enough to be fitted in the ear. From the 1950s, cochlear implants, a form of bionic ear, were experimented with. This controversial technology does not amplify sound like ordinary hearing aids. Instead it stimulates hearing nerves inside the ear to provide a sense of sound to a profoundly deaf person.

Personal choices and technology

Individuals base choices about medical technologies on many criteria. Some in the Deaf community have rejected cochlear implants which provide a sense of sound to a profoundly deaf or severely hard of hearing person. They believe sign language is a language in its own right, which defines Deaf culture. Issues of identity, politics and popular fashions guide choices about assistive technology. These include whether to wear prosthetic limbs, and how to deal with a hearing problem.

Enhancing or assisting?

Technology tests concepts of ‘normal’ body function. Scientists are working on bionic devices, which may restore and enhance body function. Technology could enhance our senses, intelligence and life expectancy. Some question the ethics of using machines to extend body function beyond what is ‘normal’. Others argue people can choose how they want their bodies to look and function.