Effect of reduced cutaneous cues on motion perception and postural control

Area of Science:

• Neuroscience
• Biomechanics
• Human Sensory Systems

Background:

• Postural control relies on sensory information, including cutaneous feedback from the feet.
• Assessing sensory deficits often involves evaluating postural performance, but the directness of this assessment is debated.

Purpose of the Study:

• To compare the sensitivity of sensory perception versus postural performance in detecting sensory deficits.
• To investigate the impact of reduced plantar cutaneous cues on motion perception and postural control.

Main Methods:

• Subjects performed mediolateral translations in the dark under normal and reduced plantar cutaneous conditions (spongy surface).
• Motion perception was assessed by perceived direction of motion, while postural control was measured using center of pressure (COP) and joint kinematics.
• Multivariate covariance analysis was used to analyze joint kinematics for subtle changes in postural coordination.

Main Results:

• Reduced cutaneous cues significantly increased the perception threshold for motion direction.
• Anteroposterior center of pressure (COP) variation increased significantly, while mediolateral COP variation showed a non-significant increase.
• Multivariate analysis revealed altered postural coordination, including increased hip strategy reliance, not evident in univariate measures.

Conclusions:

• Sensory perception, particularly motion perception, may serve as a more direct and sensitive indicator of sensory degradation than postural sway.
• Plantar cutaneous sensation plays a crucial role in both motion perception and postural control, with perception being more sensitive to deficits.