Engineering

Liquid metal sensors and AI could help prosthetic hands to 'feel'

Each fingertip has more than 3,000 touch receptors, which largely respond to pressure. Humans rely heavily on sensation in their fingertips when manipulating an object. The lack of this sensation presents a unique challenge ...

Consumer & Gadgets

Sony launches motion-sensing music effects controller, Motion Sonic

A long time in the making, Sony has just announced the upcoming release of Motion Sonic, a new technology that allows music lovers to track their own movements as they play music. Whether you are strumming a guitar or waving ...

Robotics

A helping hand for working robots

Until now, competing types of robotic hand designs offered a trade-off between strength and durability. One commonly used design, employing a rigid pin joint that mimics the mechanism in human finger joints, can lift heavy ...

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Hand

A hand (med./lat.: manus, pl. manūs) is a prehensile, multi-fingered extremity located at the end of an arm or forelimb of primates such as humans, chimpanzees, monkeys, and lemurs. A few other vertebrates such as the koala (which has two opposable thumbs on each "hand" and fingerprints remarkably similar to human fingerprints) are often described as having either "hands" or "paws" on their front limbs.

Hands are the chief organs for physically manipulating the environment, used for both gross motor skills (such as grasping a large object) and fine motor skills (such as picking up a small pebble). The fingertips contain some of the densest areas of nerve endings on the body, are the richest source of tactile feedback, and have the greatest positioning capability of the body; thus the sense of touch is intimately associated with hands. Like other paired organs (eyes, feet, legs), each hand is dominantly controlled by the opposing brain hemisphere, so that handedness, or the preferred hand choice for single-handed activities such as writing with a pen, reflects individual brain functioning.

Some evolutionary anatomists use the term hand to refer to the appendage of digits on the forelimb more generally — for example, in the context of whether the three digits of the bird hand involved the same homologous loss of two digits as in the dinosaur hand.

The hand has 27 bones, 14 of which are the phalanges (proximal, medial, and distal) of the fingers. The metacarpal is the bone that connects the fingers and the wrist. Each human hand has 5 metacarpals.

This text uses material from Wikipedia, licensed under CC BY-SA