Degrees of Freedom Problem

The “degrees of freedom problem”, as articulated by Nikolai Bernstein, pertains to the challenge of controlling the numerous independent elements or degrees of freedom (such as joints, muscles, & segments) in the human body when performing a motor task. Essentially, the human body has a multitude of ways it can move to accomplish a particular action, which can make it difficult to determine the most efficient and effective way to perform the task.
 
To address this problem, Bernstein proposed the concept of “synergies.” Synergies involve organizing and constraining the degrees of freedom to streamline movement. This simplification and organization of movements help in producing more efficient and effective actions by reducing the number of possible movement combinations that need to be considered.
 
According to Bernstein there are two main types of synergies:
1. Temporal Synergies

• These involve the coordination of movements over time. Instead of controlling each degree of freedom independently, the nervous system organizes them into sequences or patterns.

 
2. Spatial Synergies

• These refer to the coordination of spatial relationships between different segments or parts of the body. Rather than controlling each joint individually, the nervous system coordinates them in relation to one another.

 
In summary, the degrees of freedom problem in movement, is the challenge of coordinating the many possible patterns of the body to achieve purposeful and coordinated solutions. Bernstein’s theory of synergies suggests that the nervous system simplifies and organizes these movements in terms of time (temporal synergies) and space (spatial synergies) to facilitate motor control.
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