ABSTRACT
A worker who performs a simple manual task, such as picking up a box from a table, does so without much di€culty. e underlying physiological chain of events required to perform this seemingly simple task, however, is very complex and involves a number of physiological systems including the muscular, sensory, and central and peripheral nervous systems. Prior to the actual event of reaching for the box, the worker uses his or her visual system and the higher brain centers to make a judgment regarding its weight, size, and location with respect to the orientation and location of his or her body. is information is synthesized by the brain, and a movement plan is developed that will generate a series of complex control commands. ese control commands are relayed to the appropriate muscle groups (via motor neurons) to allow for smooth movement of the body segment and load unit.
