Fig. (1) Experimental setup; Participants were asked to stand on a Biodex mobility platform with an 8 degree surface tilt to assess balance stability. Electromyographic data of three muscle pairs were recorded with a mobile EMG device fixed around the waist [1]: tibialis anterior and soleus for the leg [2], biceps brachii and triceps brachii for the arm, and [3] sternocleidomastoid and semispinalis capitis for the neck. The stance protocol included the following conditions [1]: eyes open, normal head tilt and attention to changes of pressure center on Biodex display were considered as external-focus [2], eyes open, normal head tilt and attention to body oscillations were considered as internal-focus.