Hierarchical control in redundant and non-redundant postural tasks

Area of Science:

• Motor control
• Human movement science
• Biomechanics

Background:

• Previous research on postural coordination revealed discrepancies in hip-ankle coordination between redundant and non-redundant tasks.
• These inconsistencies also extended to predictions derived from the Hull-McRuer-Kohlberg-Bernstein (HKB) model.

Purpose of the Study:

• To investigate inconsistencies in postural coordination by testing the hypothesis of distinct hierarchical control structures for redundant and non-redundant tasks.
• To examine the transfer of learning between a non-redundant postural tracking task and a redundant scanning task.

Main Methods:

• A non-redundant postural tracking task was employed.
• A redundant scanning task involved 16 hip-ankle relative phase patterns ranging from 0° to 337.5°.
• The transfer of coordination patterns between these two tasks was analyzed.

Main Results:

• The transfer of coordination between the non-redundant and redundant tasks was observed to be transitory.
• A negative transfer was noted, indicating that performance in one task negatively impacted the other.
• Transfer occurred exclusively from the non-redundant task to the redundant task.

Conclusions:

• The findings support the hypothesis that hierarchical control structures differ for redundant and non-redundant coordination tasks.
• These hierarchical differences likely explain the observed inconsistencies in coordination dynamics.
• The results highlight a specific directionality in learning transfer within postural control systems.