Why does closed-loop motor control take longer to produce a movement than open-loop motor control?

Closed-loop motor control takes longer to produce a movement primarily because it relies on sensory feedback to monitor and adjust movements as they occur. This process involves continuous input from sensory receptors, allowing the brain to evaluate the effectiveness of the movement in real-time and make necessary adjustments. For example, when you reach for an object, your muscles are not only activated based on prior experience but also fine-tuned based on visual and tactile feedback as the motion unfolds.

This feedback mechanism means that the brain must wait for the information to be processed before it can make adjustments, leading to a longer response time overall. Consequently, while closed-loop control enhances precision and accuracy by ensuring that any deviations from the intended movement can be corrected dynamically, it inherently takes more time due to this complex processing requirement.

In contrast, open-loop motor control, which does not rely on feedback during the execution of a movement, is typically faster because it utilizes pre-programmed responses based on prior learning and motor patterns.