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Biomedical subjects

A H Grant

Publications and source records attributed to A H Grant.

10 recordsLinked to original sources
PubMed1992

Factors influencing hand/eye synchronicity in the computer age.

In using a computer, the relation of vision to hand/finger actuated keyboard usage in performing fine motor-coordinated functions is influenced by the physical location, size, and collective placement of the keys. Traditional nonprehensile flat/rectangular keyboard applications usually require a high and nearly constant level of visual attention. Biometrically shaped keyboards would allow for prehensile hand-posturing, thus affording better tactile familiarity with the keys, requiring less intense and less constant level of visual attention to the task, and providing a greater measure of freedom from having to visualize the key(s). Workpace and related physiological changes, aging, onset of monocularization (intermittent lapsing of binocularity for near vision) that accompanies presbyopia, tool colors, and background contrast are factors affecting constancy of visual attention to task performance. Capitas extension, excessive excyclotorsion, and repetitive strain injuries (such as carpal tunnel syndrome) are common and debilitating concomitants to computer usage. These problems can be remedied by improved keyboard design. The salutary role of mnemonics in minimizing visual dependency is discussed.

Accommodation, Ocular↗
PubMed1990

Homo quintadus, computers and ROOMS (repetitive ocular orthopedic motion stress).

Inherent conflict exists between computer systems and ocular physiology of Homo quintadus. Adverse ocular side effects of excessive saccades, excyclotorsion, supraduction, excessive field-of-fixation usage, capitas extension, astigmatic changes, otostatic reflex mismatching, and needless orthopedic malfunctions are imposed upon computer operators. Although the orthopedic dysfunctions are commonly grouped under the heading of Repetitive Strain Injuries (RSI), the inextricable linkage to poor ocular-neurological function argues for postulation of a broader schema entitled Repetitive Ocular Orthopedic Motion Stress (ROOMS). Concepts of good tool usage, total tactile familiarity, total proprioceptive familiarity, and visual cone-of-comfort clash with the installed-equipment base and indicate need for an integrated computer work station to facilitate near covisualization of screen/keyboard and to afford freedom-of-choice for optimal hand/eye synchronicity. The advocacy of computer operators' needs by user-welfare groups, universities, labor unions, and government agencies are portents for achieving genuine improvements.

Biological Evolution↗
PubMed1987

The computer user syndrome.

Most conventional computer hardware systems have been inadequately designed for the functional comfort and efficient usage by human operators. The effects of excyclotorsion, inadequate depression-of-gaze, excessive hand-wrist pronation, and ulnar abduction are discussed. The neurology of ocular movements, synkinesis, saccades, pursuits, and orthopedic hand-wrist biomechanics are reviewed. The interrelationships of these ocular and orthopedic phenomena have been synthesized into a comprehensive hypothesis, in an effort to create a computer configuration which permits a greater integration of the keyboard (tool-usage) with the screen-visualization (product-of-tool-usage), and improves visual feedback.

Computer Systems↗