Effects of passive interpersonal light touch during walking on postural control responses: An exploratory study

Area of Science:

• Biomechanics
• Human motor control
• Haptic perception

Background:

• Passive interpersonal light touch (PILT) is known to improve postural stability through haptic feedback.
• However, its specific effects on detailed physical responses like muscle activity, body sway, and joint movements during walking remain unclear.

Purpose of the Study:

• To investigate the impact of PILT on gait parameters, including walking speed, muscle activity, body sway, and joint movements.
• To explore the relationship between walking speed and postural control responses under PILT conditions.

Main Methods:

• Utilized surface electromyography and inertial measurement units to simultaneously assess physical responses during walking.
• Evaluated fourteen healthy participants under two conditions: no-touch (NT) and PILT (lumbar spine contact).
• Measured muscle activity, body sway (neck and pelvis), joint angles, and fingertip contact force.

Main Results:

• PILT significantly increased walking speed compared to the NT condition.
• PILT led to a significant decrease in neck body sway.
• Found significant correlations between changes in walking speed and neck sway under both NT and PILT conditions.

Conclusions:

• Passive haptic information from PILT may facilitate smoother center of gravity shifts during gait.
• PILT appears to enhance interpersonal postural coordination, contributing to more stable and efficient walking.
• These findings suggest potential applications of PILT for improving gait stability.