From Greg Williams (931028)
Quoted from Christopher D. Wickens, ENGINEERING PSYCHOLOGY AND HUMAN
PERFORMANCE, Second Edition, HarperCollins Publishers, New York, 1992,
page 451:
"A motor program is assumed to generate very consistent space-time
trajectories from one replication to another. A number of
investigators have pointed out that what is consistent is not the
PROCESS of muscular innervation (and therefore the specific pattern of
neural commands) but the PRODUCT of the response (Pew, 1974; Schmidt,
1975, 1988; Shapiro & Schmidt, 1982; Summers, 1989). Thus the
signature of one's name meets the criteria of a motor program. Yet the
signature may vary drastically in the actual muscular commands used
(or even total muscle groups), depending on the context in which one's
name is signed -- whether, for example, on a small horizontal piece of
paper or on a large vertical blackboard. Bartlett (1932) pointed out
that the specific muscular patterns involved in a tennis player's
swing were quite different in the different circumstances. MacNeilage
(1970) argued that the articulation of familiar words is an example of
motor programs. The product of an articulation is roughly the same
whether the speaker speaks normally or through clenched teeth. Yet the
process of muscular innervation is totally changed between these two
conditions.
"In both of these examples, drastic changes in motor patterns have
occurred. Yet certain characteristics of the time-space trajectory
have remained invariant across the modification. Thus whatever is
learned and stored in long-term memory cannot be a specific set of
muscle commands but must represent a more generic or general set of
specifications of how to reach the desired goal. These specifications
were labeled by Bartlett (1932) and Schmidt (1975) as a MOTOR SCHEMA."
REFERENCES:
R.W. Pew, "Human Perceptual-Motor Performance," in B. Kantowitz, ed.,
HUMAN INFORMATION PROCESSING, Erlbaum, Hillsdale, NJ, 1974
R.A. Schmidt, "A Schema Theory of Discrete Motor-Skill Learning,"
PSYCHOLOGICAL REVIEW 82, 1975, 225-260
--, MOTOR CONTROL AND LEARNING: A BEHAVIORAL EMPHASIS, Second Edition,
Human Kinetics, Champaign, IL, 1988
D.C. Shapiro and R.A. Schmidt, "The Schema Theory: Recent Evidence and
Development of Implications," in J.A.S. Kelso and J.E. Clark, eds.,
THE DEVELOPMENT OF MOVEMENT CONTROL AND COORDINATION, Wiley, Norwich,
England, 1982
J.J. Summers, "Motor Programs," in D.H. Holding, ed., HUMAN SKILLS,
Second Edition, Wiley, New York, 1989
F.C. Bartlett, REMEMBERING: A STUDY IN EXPERIMENTAL SOCIAL PSYCHOLOGY,
Cambridge University Press, London, 1932
P.F. MacNielage, "Motor Control of Serial Ordering of Speech,"
PSYCHOLOGICAL REVIEW 77, 182-196