TITLE:
A Learning Process Which Improves Symmetry in the Dynamics of Thoracic Rotation: A New Hope for the Amelioration of Motor Disabilities
AUTHORS:
Vinicius Monteiro Diederichs
KEYWORDS:
Spherical Coordinate System, Size Scaling, Serial Reaction Time, Motor Sequence Learning, Limb Impedance, Neuromodulation, Muscle Tone, Gravitational Force
JOURNAL NAME:
Advances in Physical Education,
Vol.9 No.3,
July
8,
2019
ABSTRACT: Intersegmental joint dynamics permit
generalisability: that is, a combination of
joints to achieve maximum attainable amplitude of one degree of freedom.
Generalisability contains the information to
configure all lesser amplitudes using many degrees. This paper describes a
treatment to reduce asymmetry in thoracic rotation, which appears to cause
motor disabilities and pain. It proposes a learning process to recalibrate the
neuromuscular system. The treatment is based on classical conditioning in which
actors receive instructions to control a specific coordinate of the dominant
hand—the conditioned stimulus (CS)—to be paired with a tensile force—the unconditioned stimulus (US). This pairing of CS with US generates a sequence of events, the conditioned response (CR). To facilitate control,
the hand first reaches the target position constraining the overall degrees of
freedom to just one. This reduces the burden on the CNS to deal with the
indeterminacy of limb lengths, the regulation of joint rotation and the
combination of multiple joints for performing the motor task. The dynamics of
this CR generates coupling, comparable to the dynamics described in coupling of posture and gait. To verify the
theory: in Experiment 1, thirteen participants with acute motor impairment
received three treatments; in Experiment 2, twenty-six healthy participants
were randomly assigned into two groups to perform the experimental treatment
with the dominant or the non-dominant hand, respectively, for comparison. Seven
variables were measured: four ranges of motion, two perceived efforts, and one pain. In
Groups 2 and 3, the improvement in thoracic symmetry was significant. The
treatment is able to trigger a mechanism that detects a critical value and
initiates a transition from the dynamics of the action system and task
constraints to a default value. Additionally, the treatment is highlighted as a
neuromodulation impacting muscle tone with long-lasting amelioration of motor
disabilities and pain.