Preface
Published online by Cambridge University Press: 23 December 2009
Summary
The numerous skeletal and muscular degrees of freedom of the hand provide the human with an enormous dexterity that has not yet been achieved by any other species on earth. The human hand can take on a huge variety of shapes and functions, providing its owner with a powerful hammer at one time or a delicate pair of forceps at another. The universal utility of the hand is even more enhanced by the ability to amplify the function of the hand by using tools. True opposition between the thumb and index finger is only observed in humans, the great apes and Old World monkeys. The human thumb is much longer, relative to the index finger, than the thumb of other primates and this allows humans to grasp and manipulate objects between the tips of the thumb and index finger. Humans have more individuated muscles and tendons with which to control the digits and have evolved extensive cortical systems for controlling the hand. In addition to its manipulative function the hand is a highly sensitive perceptive organ, orchestrated by myriads of tactile and somatosensory receptors, which enables humans to perceive the world within their reach. Taken together all these phylogenetic developments have provided humans with the ability to interact with each other, make love and war, and also to shape the world.
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- Sensorimotor Control of GraspingPhysiology and Pathophysiology, pp. xiii - xivPublisher: Cambridge University PressPrint publication year: 2009