National Geographic - UK (2022-06)

TOUC

H^ SE

NSAT

ION

Processing

unit

Electrodes

connected

to muscle

Electrodes

connected

to muscle

Electrode

connected

to nerve

SIGN
AL^ F
ROM
BRA
IN

Hum

erus

RE-CREATED SENSATION

A motorized prosthetic, controlled

by machine learning, can also

return tactile information from

sensors on the hand to the brain.

The brain sends signals

Thought translates to

impulses through the arm’s

median, radial, and ulnar

nerves to the hand.

Signals received

Electrodes implanted along

upper-arm muscles pick up

the signals and then relay

them to the processing unit.

Signals turn

into movement

The prosthetic translates

signals from the brain and

responses from the upper

arm into action.

Nerves receive signals

The sensory signals collected

by the processing unit are

sent to electrodes connected

to the median nerve.

The brain registers touch

Sensory signals are relayed

to the brain, where they’re

interpreted as the human

feeling of touch.

BONE FUSION

Traditional prostheses

fit over damaged limbs.

This removable robotic

arm is connected to

the humerus bone by a

titanium anchor, which

leads to better control

and nerve interaction—

making the prosthesis

feel more like part

of the body. Natural

mechanoreceptors

in the bone provide

additional sensations.

‘THINKING’ ARM

A computerized motor

uses machine learning

to analyze patterns

of electrical activity

related to an intended

motion in a patient’s

nerves. Some patients

practice using the arm

through virtual reality

before being fitted with

it, which trains both the

person and the unit.

1

2

3

5

6

JASON TREAT, NGM STAFF. ILLUSTRATION: SINELAB. SOURCES:

MAX ORTIZ CATALÁN, CHALMERS UNIVERSITY OF TECHNOLOGY;

DALE PURVES AND OTHERS, EDS., NEUROSCIENCE, 2ND ED., 2001