THEORIES OF MOTOR CONTROL

1. THEORIES OF MOTOR CONTROL
BY:
MANJULA.S
ASS PROF
VISTAS

2. It includes :
 Reflex theory
 Hierarchical theory
 Dynamical systems theory
 Motor programming theory
 System theory
 Ecological theory

3.  It was proposed by Sherrington in 1906
 Reflexes are the basis of movement
 Movement is controlled by stimulus response
 Reflexes combine into actions to create behavior

4.  For example, if we put our hand on a hot stove, a
reflex causes us to immediately remove our hand
before a message even gets to our brain. Other
protective reflexes are blinking when something
flies toward our eyes.

5.  Doesn't explain how single stimulus results in
varying responses.
 Doesn't explain voluntary movements.

6.  Use sensory input to control motor output
 Stimulate good reflexes
 Inhibit undesirable (primitive) reflexes
 Rely heavily on Feedback

7.  An early explicit proposal is owing to John
Hughlings Jackson, who, by the 1870s, described
the nervous system as a “sensorimotor machine”,
consisting of a hierarchy of three evolutionary
levels
 Later it was proposed by Adams in the year1971.
 The hierarchical theory states that the central
nervous system (CNS) is organized in hierarchical
levels such that the higher association areas are
followed by the motor cortex, followed by the
spinal levels of motor function.

8.  Hierarchy systems rank categories from top to
bottom. For example, in a typical family system,
the parents have the most authority, followed by
the children, then followed by the pets.

9.  The hierarchical theory does not explain how a
reflex on the lowest hierarchical level would
dominate motor function (withdrawal reflex).
 Reflex analyses based on the hierarchical theory
of motor control have been performed as part of
the clinical assessment for patients with
neurological deficits.

10.  Identify & prevent primitive reflexes
 Reduce hyperactive stretch
 Normalize tone
 Facilitate “normal” movement patterns
 Developmental Sequence
 Recapitulation

11.  It was proposed by the following authors:
 Bernstein 1967
 Turvey 1977
 Kelso & Tuller 1984
 Thelen 1987

12.  Movement emerges to control degrees of freedom.
 Patterns of movements self-organize within the
characteristics of environmental conditions and the
existing body systems of the individual.
 Functional synergies are developed naturally
through practice and experience and help solve the
problem of coordinating multiple muscles and
joint movements at once.
 De-emphasize commands from CNS in controlling
movement and emphasize physical explanations
for movement.

13.  Examples include the mathematical models that
describe the swinging of a clock pendulum, the
flow of water in a pipe, and the number of fish
each spring in a lake. A dynamical system has a
state determined by a collection of real numbers,
or more generally by a set of points in an
appropriate state space.

14.  The weakness of the model is that trying to model
such complex systems can be a very challenging
task to accomplish. In this system of systems,
defining each component or subsystem can be a
very time-consuming job. Some issues that may
rise are the data availability, systems
understanding, and systems uncertainties.

15.  Movement is an emergent property from the
interaction of multiple elements.
 Understand the physical & dynamic properties of
the body - i.e. Velocity- important for dynamics of
movement. May be good to encourage faster
movement in patients to produce momentum and
therefore help weak patients move with greater
ease.

16.  It was demonstrated by Schmidt in 1976
 Adaptive, flexible motor programs (MPs) and
generalized motor programs (GMPs) exist to
control actions that have common characteristics.
 Higher-level Motor Programs - Store rules for
generating movements.

17.  For example, The motor programme for a cricket
shot stores the subroutines in the correct order
(stance, grip, foot placement, backswing, and
follow-through). Motor programmes are the way in
which our brains control our movements.

18.  The concept of motor programming does not
consider that the CNS relies on musculoskeletal
and environmental variables to achieve movement
control. Similar commands can produce different
movements depending on changes in these
variables.

19.  Abnormal Movement - Not just reflexive, also
including abnormalities in central pattern
generators or higher level motor programs.
 Help patients relearn the correct rules for action
 Retrain movements important to functional task
 Do not just reeducate muscles in isolation

20.  Systems theory models of decision-making in human
groups and organizations emphasize their interaction
with "outside" actors and organizations and concentrate
on identifying the particular elements in the
environment of the group or organization that
significantly affect the outcomes of its decision-
making.
 Multiple body systems overlap to activate synergies for
the production of movements that are organized around
functional goals.
 Considers interaction of the person with the
environment.
 Goal-directed Behavior - Task Orientated

21.  The systems approach implies that decisions and
actions in one organizational area will affect other
areas. For example, if the purchasing department
does not acquire the right quantity and quality of
inputs, the production department wont be able to
do its job

22.  There are practical problems in applying system
theory in organizations. The problems occur to
determine the system's boundaries and identify
interrelations of the various sub-systems. How
managers have to process things is not very clearly
defined by system theory.

23.  Identifiable, functional tasks
 Practice under a variety of conditions
 Modify environmental contexts

24.  Gibson & Pick in 2000 explained this theory.
 The person, the task, and the environment interact
to influence motor behavior and learning. The
interaction of the person with any given
environment provides perceptual information used
to control movement.
 The motivation to solve problems to accomplish a
desired movement task goal facilitates learning.

25.  According to Bronfenbrenner's ecological
theory, if a child's parents are actively
involved in the friendships of their child, for
example they invite their child's friends over
to their house from time to time and spend
time with them, then the child's
development is affected positively through
harmony and like

26.  Lack of motivation for change in the environment.
 Changing lifestyles can be extremely difficult.
 Not all diseases can be prevented.
 Many people are in denial and do not believe they
are at risk.

27.  Help patient explore multiple ways in achieving
functional task → Discovering best solution for
patient, given the set of limitations