Postural control strategies enlightened by the usage of tendon vibration technique

Postural control strategies applied by a subject in two different physical environments (phy env) were explored by using tendon vibration technique. EMG data from left and right Tibialis Anterior and Gastrocnemius muscles have been received from a subject while standing still on a force platform in two different conditions (eyes open and closed) during 180 sec long trials at the phy env´s created. The subject received two 10 sec long 80 Hz vibrations applied to left and right Achilles tendon at 50^th and 120^th secs of the data collection. It has been observed that the subject experienced a motion illusion in the condition where his feet bore his total body weight with eyes closed (phy env I), which has been revealed through the analyses of Center-of-Pressure (CoP_x) and EMG data. However, when 7% of his body weight was suspended to the ceiling through a harness (phy env II) the illusion disappeared and the variability in the CoP_x signal decreased.