Most of us cringe at the idea of “death and dismemberment” when we’re filling out our insurance forms. It’s important to keep in mind, however, that there is an ocean of difference between the two. Many people are able to lead productive lives following an amputation, but it’s no easy task – a variety of challenges exist beyond the obvious loss of function.

Paralysis of a limb carries with it similar problems and challenges as well. The limb is still present, but sensation and control are lost.

Today, however, some recent breakthroughs can now overcome at least one aspect that occurs as a result of amputation or paralysis: By using the natural signals of the person’s own nervous system, scientists are able to restore some of the patient’s sense of touch.


Easing Difficulties

Here are just a few challenges that this new technology can address in those with an amputated or paralyzed limb:

Improved control for robotic prosthetics: One of the challenges with controlling a robotic prosthetic limb is telling the device how hard to grip. If a robotic arm doesn’t hold an object tightly enough, for instance, the object will slip through the fingers. Conversely, if it holds too tightly, it could crush or damage the object. The subtle control provided by feedback was not previously possible. Now, with improvements in the sensing and feedback made possible by connecting these devices to the brain, a person can detect a far wider range of pressure and even perceive texture.

Neurological and psychological benefits: Having sensory feedback where the limb was missing should cause a great improvement in the depression that typically accompanies the loss of a limb. Some studies have equated the psychological impact of losing a limb to be similar to the pain of losing a spouse. The event and its aftermath takes a severe toll on a person’s feeling of well-being. By regaining some feeling where there was none can help fill that void.

Just having and wearing a prosthetic limb has many benefits of psychological satisfaction. As this study indicates, wearing a prosthetic more hours of the day was better for relief of depression than shorter times. Having a prosthetic limb is also helpful because it makes a person’s challenge less conspicuous – their clothing fits in a more satisfying way and they feel less vulnerable because of the reduced function.

With the addition of brain control, the prosthetic limb replaces more functions. When a limb is lost, the patient may also experience phantom pain that’s created by the brain, which is expecting sensation feedback from the limb but doesn’t get any. Because these new advances provide that sensory information back into the brain, it can satisfy and reduce the phantom-pain effect.

Human contact: It may be a long time before this technology becomes equivalent to the original touch sensation, but the ability to have sensitive control to touch and feel is a huge leap forward. The technology will likely advance rather quickly as more doctors and patients test it.

As noted in the earlier study, many patients mentioned that they weren’t aware they had options during the amputation, recovery and fitting for the prosthesis. The more that word of this advancement gets out, the more its demand will increase. This will further accelerate the innovation’s development.


Great Leaps Forward

Neuroprosthetics is the name given to this advancement. As the understanding and interfacing directly with the brain improves, great leaps forward in restoring or replacing functions are happening in medical science. People who are receiving cochlear implants to regain the ability to hear sounds, and there is some early testing in which data is fed into the optic nerve for some early achievement of sight.

In the case of an amputated limb, the area of the brain that controls the limb gets an array of electrodes implanted. This brain interface can then be fine-tuned by asking the person to mimic controlling their missing limb. These impulses can be detected and adjusted in a surprisingly short amount of time. Usually within minutes or hours the patient has learned some of the control of the new prosthetic.

Once the brain is controlling the limb with relatively similar pathways to a normal limb, then the next challenge is to get the sensory feedback of touch back to the brain. This article tells the story of the development of a sensory system that could vary the information sent back to the brain. The sensory must be able to detect the variation and then increase the electrical impulse in a way that is meaningful. Ideally, the goal is to eventually duplicate the level of sensitivity of natural touch. This ambitious goal may be a little ways off, but the ability to feel and control from light touch through firm pressure is a major advancement in control.


Spread the Word

Losing a limb, or the ability to control a limb, is a major impact on someone’s life. These clever innovations, however, are making enormous improvements in the lives of these patients. Spread the word that this is possible. Maybe you can help a person regain the sense of touch by letting them know that it’s now possible!


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