Article

In response to repetitive proprioceptive disturbances (vibration) applied to
postural muscles, the evoked response has been shown to decrease in amplitude
within the first few trials.
The present experiment investigated whether this
attenuation of the response to vibration stimulation (90Hz, 5s) was muscle
specific or would be transferred to the antagonist muscles. Sixteen participants
stood upright with eyes closed. One half of the participants practiced 15
tibialis vibrations followed by 15 calf vibrations (TIB-CALF order), while the
other half practiced the opposite order (CALF-TIB order). Antero-posterior trunk
displacements were measured at the level of C7 and centre of foot pressure (COP).
EMG activity of the tibialis anterior (TA) and gastrocnemius lateralis (GL) was
also measured. Results showed that evoked postural responses as well as EMG activity decreased with practice when vibration was applied to either calf or
tibialis muscles. However, such attenuation of the response appeared muscle
specific since it did not generalise when the same vibration stimulus was later
applied onto the antagonist muscles.
CI - Copyright 2010 Elsevier B.V. All rights reserved.

Langue : ANGLAIS